Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65
Edition: Model Aviation - 1993/10
Page Numbers: 34, 35, 36, 37, 38, 39, 40, 42, 43, 65
Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65
Edition: Model Aviation - 1993/10
Page Numbers: 34, 35, 36, 37, 38, 39, 40, 42, 43, 65
Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65
Edition: Model Aviation - 1993/10
Page Numbers: 34, 35, 36, 37, 38, 39, 40, 42, 43, 65
Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65
Edition: Model Aviation - 1993/10
Page Numbers: 34, 35, 36, 37, 38, 39, 40, 42, 43, 65
Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65
Edition: Model Aviation - 1993/10
Page Numbers: 34, 35, 36, 37, 38, 39, 40, 42, 43, 65
Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65
Edition: Model Aviation - 1993/10
Page Numbers: 34, 35, 36, 37, 38, 39, 40, 42, 43, 65
Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65
Edition: Model Aviation - 1993/10
Page Numbers: 34, 35, 36, 37, 38, 39, 40, 42, 43, 65
Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65
Edition: Model Aviation - 1993/10
Page Numbers: 34, 35, 36, 37, 38, 39, 40, 42, 43, 65
Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65
Edition: Model Aviation - 1993/10
Page Numbers: 34, 35, 36, 37, 38, 39, 40, 42, 43, 65
Covering Model Airplanes Silk Robert H Munn COVERING MODEL WITH SILK impatient careless faint heart Mistakes cost money time mention embarrassment feel colleagues roll eyes wrinkles warps should bother Two important reasons satisfaction mastering fairly demanding art pleasure seeing well-finished aircraft silhouetted against sunshine taut silk also adds substantial torsional strength flying surfaces can given fairly permanent set judicious application heat manual positioning auditory effectsa drumlike ka-whoom crash sonorous resonance motor run dont Although silk punctures easily easy repair Temporary repairs can done flying field job can completed workshop Except small areas trim silk should purchased colors desired finished clear translucent finishing materials can easily apply colored tissue lettering trim stripes over silk after giving few coats nitrate butyrate dope Carefully finished silk can light almost other covering has beauty its own Since silk translucent con struction mistakes will show through covering Make tight-fitting joints seams wood structure carefully block-sand everything progressively finer grades sandpaper Finish basic framework 320- 400-grit before beginning covering process materials techniques presented have taken experience nearly approach Ive heard method works meit gives practical lightweight covering 34 Model Aviation 4PRAISE FROM JOHN POND began modeling 1929 decades since Ive read articles cover model airplanes silk Most articles gloss over covering techniques Theyre usetess modelers little no experience art covering silk contrast present article geared beginner Author Robert Munn explains aspects demanding covering technique preparation method attachment start doping finishing tells repair patch damaged componentssomething overlooked other presentation Ive seen cant recommend Muons articte highly enough Its rightful title Model Builders Guide Silk Covering Anything less doesnt acknowledge its scope Examples authors covering art 54-inch-span Powerhouse front center flanked 80-inch-span Playboy Senior foreground rear Struck New Ruler finished nitrate dope K&B Super Poxy fuel proofing enjoy its among economical techniques use example brushing dope finishes less wasteful using tissue paper paper towels foam brushes some especially first second coats prevent running foam paper absorbs dope use about three four times much necessary surface six coats wiped-on dope about half well finished same number brushed-on coats Adhesives such white glue aliphatic resins can used products heavier dope tend warp surfaces prevent easy repositioning often needed remove wrinldes during final stages covering process thats enough rationale lets get work Materials For average six- sevenfoot-span Old-Timer model will need addition silk itself about two quarts nitrate dope thinner 1/2-inchwide top-quality sable artists brush either semiround fiat 1-inch-wide sable brush dont skimp hereget best softest brush can find four five brand-new razor blades two three pieces #320 silicon carbide gray sandpaper pair sharpest fabric scissors can find pint can jar mixing dope proper consistency small jar thinner good-sized piece poster board silk cutting use nitrate dope throughout initial stages several reasons readily obtainable almost aircraft supply house inexpensive fast drying has excellent penetration adhesion easily mixed cement such Duco extra adhesive strength Most important nitrate dope compatible finish may wish put over advised begin butyrate dope its trade name varieties should expect longer drying times butyrates contain retarders lower adhesion bubbles blisters under finish attempt apply over Silk Covering Finishing 4 B C gI7 Tail Surfaces 3 2 LA 4tt@I Flat Bottom Wing Wing Top 2 ti D -. 6 Undercambered Wing\ 4 4Bottom -7 October1993 35 author Buccaneer built tram Hobby Horn partial Buccaneer 1936 Bill Etfinger design Covering kit adapted RC original Berkeley kit plans yellow dark blue trim clear K&B Super Poxy overspray it Any butyrate dope continues shrink produce gas bubbles after its apparently dry months Nonbreathing finishes such polyurethanes epoxies will eventually crack bubble flake off butyrate proprietary finish Preparing framework Fill pint container about two-thirds nitrate dope one-third thinner Dopes supplied different firms vary somewhat density aim consistency slightly heavier wateryou want first two coats soak well wood Apply mixture /2-inch sable brush part framework will touch silk means stringer rib spar longeron etc will come contact part silk thinned nitrate adds little weight slosh liberally will soak well helps achieve good adhesion around edges contributes finish failed coat ribs stringers example would soak up first few coats dope making finish very uneven later stages Allow initial coat dry thoroughly preferably three four hours longerin low-humidity climate Lightly sand framework #320 silicon carbide leveling raised rough grain sure surfaces smooth avoid snagging covering later youre satisfied brush second coat dope dope dry takes less time first coat again sand surfaces lightly time will have used about half pint thinned nitrate dope Refill container unthinned dope making mixture slightly thinner say 30-weight motor oil Coat entire framework third time thicker mixture flowing liberally outline longerons leading trailing edges areas edges covering will secured undercambered wings squeeze entire contents 1-ounce tube Duco cement four-ounce bottle tight cap Fill top unthinned nitrate dope stir until mixture uniform Apply liberal coat thick mixture surfaces bottom wing spars rib between trailing edge main bottom spar usually about 30% chord will almost certainly guarantee good adhesion silk concave area undercambered wing Keep tightly-capped mixture field box because will handy making field patches Covering fuselage Trim silk about inch overhangs principal longerons Make overhang slightly longer cowling area front windshield will wrapped least center possibly beyond Try single piece grain silk paralleling fuselage centerline 36 Model Aviation en nose area fuselage side smooth out carefully Dampen entire panel pull silk taut lengthwise dope down large area Keep grain straight possible keeping grain straight Attach silk firmly rear Gently pull out wrinkles along straightest line side stringer adhering about six inches time Attach damp silk along center stringer Pull out lengthwise wrinkles maintain lengthwise crosswise attach opposite edge panel tension small sections doped Lengthwise tension required rear down must splice silk vertical members Wherever splice anticipated wise give few coats dope edges part questionupright longeron stringer sparso first piece silk can wrapped slightly around edge eliminates possibility loosening first piece second edge doped top Careful trimming needed covering rounded oval fuselage lengthwise strips may find handy lay dry silk over plan lightly mark oversize outline soft pencil ball-point pen trimming away reference line razor blade scissors cut piece need Lay dry silk smoothly possible over section covered Spray Left After rib center undercamber has adhered lightly rub area hasten drying help adhesion center area lightly water dispensed fine mist pump-style container sort used household cleaners Grasp silk nose end pulling slightly dampen forward area same toward tail Its possible adhere silk using plain nitrate thinner small brush provided undercoats have sufficiently heavy prefer dilute dope remaining original pint can adding thinner use small brush Put stripe dope over woodsupported area opposite arrow ends front area marked 1 illustration use finger smooth silk tightly against wood pulling along vertical line Its important keep silk slightly damp times spraying intermittently required get sopping wet risk warping framework greatly slowing adhesion process Paint thin coat dope through silk area 1 smooth against October 1993 37 Use sharp tailors scissors trim dry silk about inch oversize way around section covered silk dampened light water spray near wing center section gently smoothed chordwise wrinkles out dope silk down center section Check sure edges firmly attached Pull moist silk taut spanwise Gently work silk chordwise beginning center wingtip spanwise around wingtip doping dope down small section near tip down small sections go center Work way along edge other pulling gently chordwise doping down about six inches time Attach silk around edge trim sliding new razor blade along reverse edge maintaining slight tension Undercamber adhere center section Dope silk down along undercamber spar chordwise pull taut along bottom Ribs spar need good dope base spar point max undercamber assure good covering attachment adhere tip Gently tauten silk spanwise work toward trailing edge brush dope adhere silk ribs supporting wood use fingers might prefer piece foam paper towel remember fingers dont leave lint bits Allow dope set 30 seconds making sure entire area damp pull silk taut lengthwise grasping edge reararea 2and paint dope through silk area Maintain slight tension few seconds until adhesion sets Again rubbing lightly finger will improve adhesion speed setting Working along upper edgeareas 3 5 7pull silk smooth being careful distort horizontal grain silk same along bottom edges Concentrating area 3 pull silk smooth brush dope through along topmost longeron Work front rear Move bottom area 4 again working front rear pull silk bit tightly perfectly smooth vertical plane maintaining slight rearward horizontal tension adhering edges go Work areas 5 6 7 8 similar fashion slight wrinkles puckers develop approach rear area 2 use straight thinner brush loosen rear silk apply slight amount tension smooth sure silk remains slightly damp throughout Cover opposite side same way Returning first side use new razor blade neatly trim overhanging silk along longerons Carefully run blade along edge longeron apply small amount dope along cut edges smooth firmly down covering curved fuselage lengthwise strips dont trim silk exactly along edge longeron stringer Instead trim about l/ 46 inch away supported edge run dope along edge wrap silk toward center fuselage along edge longeron stringer will prevent lifting first silk panel adjacent applied after just-covered edge has coated some thickened dope/cement mixture areas have worked damp will turn white set called blushing caused moisture evaporation will disappear fresh thinned dope thinner brushed over areas later Cover top bottom fuselage similar sequence except trimming silk should leave about 3A6 inch along edge overlap side panels completely cover supporting balsa Covering tail surfaces See illustration B Cover bottom first trimming silk about inch oversize laying over prepared framework Dampen center area pull silk chordwise area 1 dope through adheres sheeted center area center ribs unsheeted surfaces dope has set firmly dampen entire area Pull silk spanwise area 2 doping through along two- threeinch area wing tip same opposite tip area 3 Beginning adjacent area 1 pull silk gently chordwise work outward toward area 3 doping silk spar trailing edge go Take care distort spanwise direction silk grain Now work along area 5 center outward pulling slightly chordwise spanwise assure smooth covering Any necessary adjustments area 3 can made loosening edge thinner gently pulling silk taut Repeat process along areas 6 7 Go back around edges wrapping silk little past center around edge Use dope finger pressure achieve smooth wrap Avoid loosening previously adhered areas Use new razor blade trim off surplus silk just past centerline edges top covering will overlap bit Cover top surface same way covering other tail parts dope down longest straight edges first pulling silk taut go cover small area opposite center just-covered edge Remember keep silk damp times Begin end long edge work way around small area just covered pulling silk gently smooth out wrinkles Cover opposite edge same way adjusting necessary thinner gentle pulling Covering wing See illustration C As stabilizer cover bottom first may possible cover entire bottom surface piece silk would difficult maintain proper orientation grain both wing halvesand have work half time anyway prefer use four pieces cover wing technique similar described fuselage tail surfaces Trim silk oversize lay dry prepared surface Dampen area near wing center pull silk taut chordwise 38 Model Aviation ilizer Dampen trimmed silk place tauten chordwise adhere along fuselage joint Dampen entire panel pull taut spanwise adhere along trailing edge wrapping about around edge Pull silk gently spanwise chordwise along remaining edges eliminate wrinkles doping down go brush dope adhere center sheeting rib single rib center dihedral break trim silk about /16 inch beyond rib wrap around edge dope down firmly vertical surface rib Dampen entire area pull silk taut spanwise area 2 adhering wing tip Starting center work way along area 3 toward tip doping down about three inches time pulling slightly spanwise well gently chordwise maintain spanwise orientation silk grain Begin wing center area 5 keeping silk damp work way toward tip pulling bit firmly both chordwise spanwise Work way around areas 4 6 pulling silk taut adjusting area 2 required eliminate wrinkles Use procedure wings having flat convex bottoms top surfaces well Remember wrap silk slightly around edges trimming described tail surfaces Undercambered wing bottom See illustration D Attach silk chordwise wing center Make sure dope has set firmly dampen entire wing surface pull silk firmly spanwise area 2 along bottom spar same area 3 Dope down silk firmly areas 2 3 wing tip Make sure youve applied extra coat thickened dope/cement mixture along bottom spars ribs Dope silk firmly rear spar working center tip taking care maintain spanwise orientation silk grain Again working center outward attach silk rib begin rear spar gently slide finger along rib toward front spar after brushing dope Dont take time now adhere silk forward portion rib Working toward trailing edge adhere silk rib behind rear spar maintain spanwise tension important chordwise tension undercambered wings its useful pull silk spanwise area 7 dope down small area Cover remaining ribs same manner attaching silk first between spars toward trailing edge finally along trailing edge inward toward area just covered As near wing tip loosen areas 7 2 thinner adjusting tension necessary eliminate wrinkles Keep silk damp Using gentle chordwise tension work along leading edge wing center outward along areas 5 6 opposite bottom panel same manner have applied adequate base undercambered ribs silk will adhere well especially run thin bead dope along rib press silk firmly against Too much chordwise tension will cause problems use just enough keep silk smooth Yes tedious takes some practice think happy youll its finished Polyhedral wings Cover four center panels before moving tip panels technique same flat-bottomed wing except silk wrapped onto vertical surface dihedral-break ribs prevent its pulling loose tip panel covering applied Brush two coats thickened dope/cement mixture strip about /t6 inch wide along dihedral-break rib assures adhesion next piece Carefully trim inboard edges tip panels slight curve maintain orientation silk grain tip panel sure panels adhered firmly dihedral-break rib before beginning apply spanwise tension find silk has pulled loose undercambered area drying spray loosened area fine water mist Run bead thinned dope along area rib involved rub silk down firmly against rib extreme cases can trim piece 162 plywood match undercamber rib use press silk against rib until has set firmly takes perhaps three five minutes Trying hasten process heat gun would add headaches causing silk become taut much faster dope can dry Finishing silk must allowed dry least 12 hours before proceed finishing plan use butyrate dope point finishing process begin now Translucent surfaces have doped nitrate butyrate may develop unhealthy mottled appearance Remember nitrate dope will happily accept almost finish whether intended fuel proofing strictly trim Nitrate does continue shrink over long period time butyrate does use nitrate time objective fill silk dope evenly possible minimizing October1993 39 Author Munns 84-inch-span Powerhouse covered yellow blue silk uses 08 61 four-stroke engine authors 74-inch-span version Henry Strucks 1940 New Ruler covered white blue silk Robert Munns 9-foot-span red Dallaire Sportster uses Enya 90 four-stroke Finish Sig clear butyrate 1WATER JET CUT CARBON FIBER STRIPS Latest Technology No Sanding Necessary Smooth Edges Great Spar Caps Precision Cut Strips Foam Wing Reinforcement Bondable Surfaces Lowest Prices CLi 001 Thick 1/4x4t 2/pIg 5350 3/tx48 2 pkg S425 CL2 014 Thick 1/4x48 2/pkgl S450 3/8x4t 2 pkgl 5600 CL3 022thickl l/4x40 2/pkgl S550 3/tx48 2 pIg 5800 CL4 030 Thick f/4x48 2/pIgl 5650 3/tx4t 2 pkgl 51000 Send SASE information additional sizes products Add $500 shipping handling Ca 11 residents odd 775%taa Onerseasordersadd 15% OrderCODMC/ VtSA send check money order Aerospace Composite PIqct PO Box 6621 Irvine 92114 14 250-1107 Fax 74250-0307 2 - NinE EUNE DEE DEE E EU EU SIG GLOW FUEL MANUFACTURED WITH THE PUREST FINEST QUALITY INGREDIENTS AVAILABLE * Superior Igniters Improve starting idle acceleration Youll notice power bargain fuels * Special Detergents Promote Clean burning prevent residue buildup * Rust Inhibitors Protect engines corrosion After run oil needed engines * Film Strength Additives Increase lubricity provide extra lean run protection * Anti-Wear Additives Help keep engines running peak performance longer * Satisfaction Guaranteed 0% Nitromethane 5% Nitromethane 10% Nitromethane 15% Nitromethane 25% Nitromethane 3506 Nitromethane SIG CHAMPION 2-STROKE FUEL PINTQUARTGALLON $995 $325$495$1295 $395$535$1495 $395$625$1695 $495$795$2295 $595$895$2795 SIG PREMIUM 4-STROKE 1 OOh Nitromethane 15% Nitromethane SIG ALL-CASTOR FUEL 5% Nitromethane 20% CASTOR 10% Nitromethane 20% CASTOR 15% Nitromethane 20% CASTOR 5% Nitromethane 25% CASTOR 100k Nitromethane 25% CASTOR FUEL $1395 $1625 $1295 $1495 $1695 $1395 $1595 THE CHOICE OF CHAMPION FLYERS over 20 years SIG has blending finest quality model engine fuel available using finest quality ingredients instance Methanol use 9950k pure very best grade money can buy also use real 1000k pure Nitromethane get full measure youve paid based honest percentage-of-volume method percentage weight SIG fuels excep tion All-Castor Fuels contain 50-50 blend Bakers purest AA Castor Oil new improved Klotz Techniplate Synthetic Racing Oil maximum engine lubrication protection Based experience sincerely believe finest quality fuel can made price dont take word try some judge yourselfl PREE SHIPPING ON ORDERS OVER $1500 BUT ALL ORDERS ARE SUBJECT TO $6OOIPkg UPS HAZARDOUS MATERIAL SURCHARGEPrices sublect change notice Toll Free Orders 1-800-247-5008 Modelers Hotllne 1-800-524-7805 Letest cetalog $300 SIG MANUFACTURING CO INC.. Montezuma IA 50171 U U I I I I p U U U I I i I U i I p droplets runs thorny problem has attacked angles including use various types sizing such spray-on starches gelling agents anything likely prevent blobbing finish Nearly techniques add lot weight well odd tones coloring Smearing dope-treated surface paper towels foam brushes does help prevent runs technique also wastes tremendous amount dope coats required obtain satisfactory finish technique use avoids drawbacksthough does tax ones patience dexterity too-thin dope mixture will seep quickly through silk forming runs droplets too-thick mixture prohibits smooth brushing So trick thin nitrate slightly Remember brush pressure will force dope through silk quickly unevenly takes some practice develop gentle quick onetwo-three brush stroke once mastered youll have forever Never brush dope three four strokes dope sets up quickly softest sable brushes will leave ridges brush must touch silk gently motion moving perhaps two inches immediately back about three inches back along same path about three inchesand thats Overlap previous strokes slightly move quickly Work area about four inches square Hold surface horizontal gravity will draw dope downward through silk Immediately turn surface upside down work area about same size Immediately turn surface over again brush area adjacent first takes some dexterity flip fuselage other surface back forth learn liquid dope remains suspension within weave silk doesnt stay position long enough gravity cause runs form droplets notice incipient run droplet forming surface just turned upward simply brush out very lightly quickly obtain spread Remember continue turning surface over few seconds have stopped applying dope takes about two minutes first somewhat heavy coat dope set adequately prevent drops runs As dope sets surface will have uneven appearance because slight variations thickness dope wont cause blobs runs thoroughly dry surface will appear almost perfectly uniform rather tiresome technique should fill weave about 90% first try Once surface has set few minutes small unfilled areas mostly around edges brushed applications will readily apparent Although its less critical keep dope suspension Continued page 42 40 Model Aviation U U U U U p U U I U U U U I HUE EU RU5 EKEEKEE HOW OFF THAT NEW PLANE Once youve used sturdy hardwood FLIGHT STAND youll never go flying again FITS ALL SIZES OF PLANES including Quarter Scale models padded cradles open 9 TWO TRAYS lower holds favorite flight box upper keeps starter transmitter ete within easy reach STABLE enough hold plane securely THE BEST PART folds compact 4x24x36 transport storage Use home flying field Shipped fully assembled ready favorite finish Call prices info larger custom built sizes Only $9995 CA residents add sales tax FREE uPPING U TOYS BOX 297 GRENADA CA 96038 916430-2563 AT TII OEC C~4Xt revolution aerosol paint technology 21St Century Paints advanced formulation provides modelers fast drying easy apply finish designed withstand punishment RC flying 21st Century Paint dries dust-free 15 minutes Additional coats can applied three minutes Within 12 hours 21st Century Paint fuelproof up 15% nitro can masked striped decaled Only 21st Century Paint comes new hi-tech nozzle sprays fan pattern similar airbrush can adjusted either vertical horizontal fan spray unique patented nozzle system offers increased control reduces overspray resists running better conventional round pattern nozzles found other paints 21st Century also amazingly insensitive weather conditions during application Thanks unique formulation gives extra flexibility 21st Century Paint highly resistant chips cracks scratches 21st Century Paint available 1 colors sandable white primer Welcom space age model finishing ii COVERITE S 420 BABYLON ROAD HORSHAM PA 19044 PR RounduplStyles Continued page 41 story too involved tangled detail last item lessons learned experience 1 A public example poor flying manners can cause problem 2 Upset wrong people potential big problem arises 3 What affects flier can soon affect fliers 4 Clubs must develop good public image part community positive way 5 Never underestimate would shut down oppose dont always know motives interests 6 Work together support other Numbers count must become involved retain flying privileges no matter live fly 7 Support national organization AMA can help Academy gives local clubs stature face problem can coordinate lobbying PR effort interest next month jMunn Continued page 40 first pass its still better touch up several unfilled spots surface flip over ones other side worst over Thin nitrate dope bit can lengthen brush strokes dragging presages too-rapid drying brush marks thinner consistency usually better Brush coat surfaces allow set day Lightly sand edges #320 siliconcarbide paper Use old piece same grit gently sand along ribs spars longerons stringers touch silk covering job should look pretty good nowbut youre finished yet point can either brush spray depending equipment facilities have hand tend brush suffer slight brush marks inevitably creep About four thin coats later start thinking about trim wish use contrasting tissue stripes numbers cut neatly lay place dry spray light water mist Using fingers gently rub tissue smooth brush coat thinner through tissue adhere evenly silk dark tissue color works well over light-colored silk reverse doesnt apply initial adhesion dry complete brush two three coats thinned nitrate dope youre going mnning diesel engines ignition engines using gasoline 42 Model Aviation l might consider aircraft finished point will however still able see grain silk youll need about six thin coats dope almost fill completely Dont try accomplish two thick coats brush marks grossly uneven areas will rob pride workmanship have working butyrate dope may wish add about two thinned coats some form nontautening agent has added Aircraft supply houses normally sell both tautening nontautening varieties both butyrate nitrate dope butyrate its good idea use nontautening variety last three clear coats since will somewhat lessen strong shrinking tendency butyrate like add durable fuelproof finish over nitrate dope especially engine area rest fuselage Im using high-nitromethane fuels twostroke engine spray surfaces two thin coats K&B Super Poxy imparts high shine very durable gas diesel power spray generous coat fuselage color trim almost always use K&B Super Poxy color overspray remaining translucent silk-covered areas clear variety Patching Small slits punctures can readily drawn back together Duco cement Run bead cement along edges possible use pin carry cement undersurface silk near edges pin can useful guiding torn edges together cement will set quickly Later sand surface lightly overspray either dope epoxy whichever used final finish youre working larger slit tear use pin carry cement along edges further soften cement wetting area about /2-inch wide side tear some thinner small brush Quickly lay small piece plastic wrap over area making sure wetted areas drawn up level against plastic Strip off plastic wrap area beneath has dried have surprisingly good repair job damaged area too large too badly torn use techniques try Trim silk back nearest supported point such rib spar Lightly sand around edges #320 silicon-carbide paper Pay special attention epoxy-coated surfaces since want sand through epoxy nitrate coating underneath Brush 3As-inch-wide strip dope cement mixture around perimeter Trim piece silk overlap edge opening 3As two adjacent sides leaving about inch long remaining sides Lay piece over opening dampen fine water spray Smooth silk evenly along closely trimmed edges adhere Continued page 65 UNLEASHthePOWERfromWITHIN Bigger Engine Wont Fit typical 45 will turn 13-6 over 10000 get 3 minutes oz & idle well below 2000 r er Props r Economy Less Noise No Glowplugs Low Idle Ask local dealer call br complete cataleg send self-addressed 75C stamped #10 envelopo S 8200 credited 1st order L DAVIS DIESEL DEVELOPMENT lux 141 ord CT 00410 Sh1-1170 4 4 NORTHEAST AERODYNAMICS Inc 150 Robinson Rd Hudson NH 03051 SUPERIOR DESIGN- & CRAFTSMANS DEL-A IRO Finest Kits Youll Ever Buy Build Train-Air 20 Train-Air 40 Sport-Air 40 Bel-Air 40 40 Hydro-Floats need easy handling superior aerobatic modern looking sport exhibition biplane haa filled Eel-Air 60 kit parta thia biplane tine line kital mechine Cut assist building real ahow atopper Bel-AIr 60 has fully aummetrical wing aectiona gives greatest potential acrobatic performance either upright Inverted ship capable very slow close-in type flight right up rigorous acrobatic schedule can muster Engine Requirement Wing Span Wing Ares Fuselage Length 60 52 935 c IIUN features two new ignmon systems uris compleat electronic package mechanical advance systems will replace other popular systems give great relebility other re#um step unit two position RPM controlled advance system order keep costs line presant times units will offered less switch harness systems feature diode battery protection reg ulated power supply Th regulated supply provides low battery draw acodentally left full power high RPM end reduced RFI ewisslon wimpy units feattae ftil power will fire twins needinq five cell batety quality IS Inside OPECiPiCATIONS Fuselage Width Weight Range Wing Loading Range 35 6 75 lbs 14510 185 603-881-5899 Visa & Mastercard Accepted October 1993 43 DIESELIZE its AWESOME Ask about Granite State R C Products Suppliers quality radio controi parts accessories division Northeast Aerodynamics S cyiman auvance system-$6700 cylmech advance system --$9600 Single cylstep advance system---$8700 Twin cylstep advance system 600 Single cylelectronic adv system-$1 1200 Twin cytelectronic adv system---$1 4100 Switch harness Deans plug $1100 Stitt M-80 Plug 1/4-32 $1100 Shipping$600 3on 2nd day air : cor RO EloctricslKopski Continued page 64 approach question light aspect reason can fly well lower-power installations strong part permits carry heaviest stuff So now just imagine same plane flying well economy can motor seven cells massive power installation geared cobalt 40 21 cells Its plane motor syndrome Imagine Okay. can anyone guess what toughest part design landing gear Consider must light low-power end strong heaviest installations compromised gear double 1/ inch-wire struts could made lighter lower end stronger other extremean argument customized landing gear over power system range Maybe Ill try sometime So much column Please include SASE correspondence youd like reply Happy Quiet Safe Electric Landings Everyone ng FunlMathews Continued page 46 Wasp photos show McCoy 049 diesel span3 1 inches chord4 inches finish AeroGloss dope flight path left under power right glide Now slightly enlarged version Perry Eaton Kenai Alaska spans 90 inches powered OS 61 fourstroke addition radio control assures flight will like Keith Laumer described Additionally Paul Denson designed published double-sized version Laumer design calling Twin Lizzie OMT MAN April 1978 version three channels RC 20-cubicinch power plant Im reasonably sure full-size plans either version available MAN Certainly looks like flying fun JMunn Continued page 43 edge neatly uniform application thickened dope/cement mixture Allow patch set few minutes pull silk taut along other trimmed edge 90 angle first Keeping silk damp pull taut other two directions adhere around edges Allow surplus material remain place minute two place new razor blade vertically about 3/is inch patched opening pull silk edge up against blade cutting material along length blade Move blade farther along edge repeat process until edges neatly trimmed Any stray strands loose spots can tacked down dope After patch has thoroughly dried apply medium-thick coat dope flipping surface over back few times achieve good fill coat apply several coats thinned dope Later can sand area lightly especially around edges add few coats dope over newly covered area before applying final finish coat sure apply enough coats dope Well-finished silk can last years especially some form plasticizer has added dope prevent overtautening few drops castor oil used plasticizer earlier years modem nontautening dopes contain advanced chemicals Once have mastered technique covering models silk youll have unparalleled satisfaction handiwork * 0 FThaliy An Engine Mount stern Wont Shake Rattle Roll fly model planes dont have tell theres whole lotta shakin goin now theres something can about Sullivan Flex Mount System Its engine mounting sys tem has specially designed rubber isolators absorb engine vibration reduce noise anct limit wear tear modeL thats Flex-Mount comes aluminum adaptor plate makes easy mount 40 60 90 two-cycle engines firewall strap mount beam mounting four-cycle engines So dont jitterbug Thik dealer Sullivan Flex-Mount engine mount U ing system thought rock roll F PRODUCTS wouLd never dieP0 BOx5166BaltimoreMD21224 Getting Better Ideas Off Ground October 1993 65