Radio Control Scale Bob & Dolly Wischer FIBERGLASS over foam An engine cowl its compound curves con tinuously changing shape airplane part lends itself fiberglass-overfoam construction methods Blue styrene insulation foam used because easily cut formed has rigid cell structure white foam ordinarily used wing cores can sawed rough shape hand band circu lar saw circular saw can some what hazardous because fast-moving blade can melt foam causes seize blade violently sudden action can pull operators hand blade least troublesome method cutting foam electricallyheated nichrome wire Look Styro foam under Insulation Materials Yellow Pages find local supplier useful thickness foam sheet two inches permits foam core built up minimum number separate pieces Polygonal templates used foam-cutting guides hotwire method use /6- %2-in plywood guides can made stiff material wont ignite contact hot wire guides held manually both sides foam block hot wire cuts smoothly around peripheries make side blocks cowl form Two foam blocks can stacked both sides can cut operation desired four-inch total thickness about maximum can held average mans hand Top bottom blocks fill space between sides cut similar manner same ply guides used cut angles block ends match sides Foam blocks quickly assembled cementing four-minute epoxy maintain cowl shape meets fuselage front surface plywood former built cowl avoid problems warping plywood prefer laminate least two thick nesses ply former using white glue pressure C-clamps cowl shown photos former consists two laminations 3A2-in plywood Because difficulties have alignment fuselages past bulkheads now made process laminations sandwiched between %-in ply boards clamped glue dries Bulkheads gain enor mous strength come press abso lutely flat stay way outside shape former cut match fuselage front surface reduced size around its edge allow expected thickness fiberglass cloth resin applied later average cowl dimension could about 045 Y64 Adding three four layers fiberglass cloth over outside core will bring outer surface up fuselage dimensions Holes cut ply former clear engine muffler engine mounts throttle control few extra holes weight reduction 44 Model Aviation Bob going show us oasy make fiberglass-reInforced resin cowl starts L raw chunks blue styrene foam cuts using plywood templates hot wire Next R roughly-shaped foam blocks epoxied together plywood templates foreground likes blue foam because carveslsands easier has smoother surface Cowls laminated 6-ln plywood baokplate has cutouts clearance engine muffler 1 large round holes weight reduction Next Center ply backpiate spot-cemented foam core readiness shaping cowl fit side-mounted engine Finally R foam has carved sanded its exterior shape Styrofoam sands little effort make sure wear dust maskl Bob has little tips process column first layer fiberglass cloth being applied over foam core epoxy glue 1 Three layers will follow Once shell has completed Center foam chipped away interior p reparation mounting fuselagepositioned steel dowel p ins Finally R fiberglass cowl has sanded fine finIsh ready primer paint four-layer glass cowl exceptionally sturdy Note smoothly forward cutouts have finished assembled foam blocks spotcemented ply former again four-minute epoxy Carving foam rough shape done sharp knife used slicing action blue foam carves easily balsa Shaping foam its final form done No 60 aluminum oxide open-coat sandpaper over block operation must done care very easy remove too much foam especially corners polyester resin used bind layers fiberglass cloth foam must protected will dissolved resin Pores foam should filled generous coating vinyl spackling compound Sand smooth add another coat compound sure areas really covered Since want glass cloth come close contact plywood edge will maximum adhesion compound kept off plywood Scrape sand expose ply edge cowl using epoxy resin binder done cowl shown vinyl spackling coating required epoxy will attack styrene foam Some modelers using polyurethane foam cores fiberglass layups havent used material because preferred foam-cutting method hot wire have warnings about breathing fumes develop during cutting polyurethane foam cutting done saw knife sandpaper polyurethane foam has advantage affected polyester resin protecting layer vinyl spackle isnt needed curing processes polyester epoxy resins same cowl made polyester rock-hard ready sanding 24 hours epoxy takes twice long Polyester finishing resin sands fine powder mini mum effort regular resin used boats auto body repairs sands greater difficulty Epoxy resins come variety types some sand ease Hobbypoxy No 2 used sands well after about two days harden ing considerable effort needed epoxy-resin cowl will withstand much abuse nose-over landings cowls have made three four layers cloth long life greatest resistance fracture Allowing 045 buildup would require about four layers quick buildup use heavy six-ounce cloth first three layers follow top layer 2Y2-oz cloth has finer weave needs less primer smooth paint base weights mentioned square yard material six-ounce cloth forms around com pound curves difficulty Scissor cuts will permit some overlap curves lumps result removed coarse sandpaper before application successive layers Other irregularities due runs resin thickened spots also removed layer Excess cloth resin edges best removed just after resin sets up before hardens completely trick real labor-saver removal excess can toilsome later Hardened edges can also removed small circular saw Dremel grinder best primer paint adhesion remove gloss exterior surface sandpaper starting No 60 working up No 150 finer grades can used hardly worth ef fort because primer will fill small sand paper scratches As aspects Scale modeling sandpaper makes differ ence Dont waste time effort fine sandpaper except few final swipes smooth out scratches Coarse paper does heavy work level ing surface Sanding through top layer during leveling isnt catastrophic three layers remain underneath Ex tra primer spots sanded through will avoid visible weave showing through paint foam can now chipped out cowl interior Use handy tool such broad screwdriver blade cowls interior surface smoothed No 60 sandpaper engine-cooling hole cowl front cut Dremel Continued page 131 A. Yi iia THE WW II TRAINER Recreate excitement young USAAI pilots first experienced AT-6 No other militaty trainer has brought back fond memories During MN ii AT-6 irnvlwd training nearly pilot Imagine feeling freedom sense power made airplane famous NowCircus hobbies introduces flrstAT-6kitdesigned realistic four-cycle engines high quality balsa lilt will enjoy building well flying includes lots hardware accessories aluminum cowling realistic molded canopy along full-sized plans decal set Can bulltforfixed retractable landing gear includes landing flaps Get started first mission todayl Orders Toll Free Lf~J82-0022 Customer Service 702 732- 0022 $150 Circus Collection Catalog EU RUE UWJE EJE U mru IYA Specfficatlons Length 495 inches Wing span 725 inches Wing area 775 sq inches Weigtit 95-11 lbs Engine. 90 12 cu Four Cycle RadIo 5 6 channel Special INTRODUCTORY Combination AT-6 lUT Regularly $18995 OS EfIYA 120 Webra 91 Ibur Cycle Reg COMBO $52520 3132 South Highland Dr Las Vegas NV 89109 Kit $15995 Offer expires first month issue Limited quantity hand July1985 45 accidental engaging winch should foot switch left Weve photos winch/retriever combi nation come Tony Spetebroote Falmouth MI No details construc tion provided except say its easy move about retrieving portion unit works fine like Burts circuit designed safety mind eliminating foot switch Tony points out accidental turning winch practically eliminated uses knee activate unit claims excellent results Well whatever safety features read about use launching hardware system 200-meter band saw its running Keep safe Good lift Dan Pruss 131 E Pennington Ln Plainfield IL 60544 responding advertisers mention read about Model Aviation RC Scale/Wischers Continued page 45 grinder Robarts Rough Tough car bide cutters make short work job An alternate method drill row holes file through remaining material Final finishing hole done sandpaper wrapped around short lengths woOd dowel various diameters preferred locating method alignment between cowl fuselage front means three four steel dowel pins made short lengths R-in-diameter music wire Holes pins drilled cowl backplate formet before foam cemented place certain accurate registry Final sanding match cowl fuselage done pins place High spots sanded down until fingertips can feel no change level Low spots built up Sig Epoxolite Hobbypoxy Stuff dowel system two machine screws needed secure cowl can threaded convenient spot such front ends engine mounts Will fly fellow transmitter hands about fly first RC Scale model asks himself foregoing question pilot has some basic knowledge RC flying skills has reasonable success trainer types answer certainly affirmative Build ers Scale models kits magazine plans have reason assured airplane will perform satisfactory manner no special piloting skills essential assumes course model accurately constructed has correct control surface travel proper weight distribution no warps overweight Any faults can send model back workshop plastic bag Inaccuracies show up unexpected places Wing tail surface incidence angles should checked during construc tion Making changes angles after model completed means builder must cut finished surfaces wing stabilizer temporarily fastened position fuselage model set up flat surface measurements made fuselage referContinued page 134 July 1985 131 OPSs Little Pride Joys. modeler takes pride owning quality engine OPS offers Ursus 60 RC SLA 40 RC Both engines have ABC piston sleeves Schnuerle por& - dual ball bearings come OPS slide valve carb muffler Check out OPS engines local hobby shop have engine will proud own Parts People Post Office Box 26247 Orleans Louisiana 70186 242-5967 IN STOCK FOR IMMEDIATE SHIPMENT NEW RA 505$19995 New Onedro 39 CDI$10995 Reg Onadra3fi $9996 Brloigholloflywheol$11995 Re9 Qoodro 36 Power Aooewbly Only$6490 QUADRA REPAIR$1000 pine porte Jin Meoser ERCOUPEPLANS $2396 KIT $23995 Jin Meoner TOMAHAWKPLANS $2396 KIT $29996 Jiw Mooner 9BALL TRAINERPLANS $1996 KIT $19996 BALSA end BASSWOOD oil oboeSig pricee Ieee 10% Now ZENDAH G-23 $13996ZENOAN G39 $ 9996 FLOATS 3915 0001noree $1796cowplene kit $3996 FLOATS4914ecole noree $2196oowplene kit $4796 19 90W WHEELS 3995 P&W CVIS FLEET5$2596 PLANS SUPER STEARMAN 14 Godfrey$2995 STARDUSTER TOO 14 IBrieIgheIlo 13 J3 CUB Nelit$2995 VOLKSPLANE 13 Chicken ChorIle02395 COCKPIT KITS Towohnwk F4U1 Spitfire ME199$2395 Erneepo Fleet J3 Cob P95 P47 C 5091092195 Citebrie $2495 Zero $2995 Zero enferior$1095 US Doedro FUEL TANKS16 $99632 no $795 FIBERGLASSARROWSHAFTSB16n23long9$1996 24-Hour Service. Add $250 postage Send Bank Check Money Order JIM MESSERS QUALTIY MODEL PRODUCTS Valley View Dr. Boo 43 Allegeny NY 14706 M52LMP1000 $2500 ca includes shippIng UPS COD add $200 $600 plans CA add 6% Dealer Inquiries invited LINDSEY MICRO PRODUCTS 160-A No Fairview Ave SuIte 104 Goieta CA 93117 805 683 2042 After 5 pm PaCIfiC Both require TWO Channel Radio Mini Servos 250 MAH BATT wood construction include hardware needed Consumers Guide MA ISO Ott St Marrlsonburg VA 22801 Address RC Scale/Wischers Continued page 131 ence line leading trailing edges down surface certain agree construction drawings Robart incidence meter helpful time also desirable check horizontal alignment wing stabili zer measurements sighting rear sighting done dis tance about five eight feet viewing straight along fuselage centerline comparing distance stabilizer tip wings surface fin also checked certain truly vertical parallel fuselage warped wing will adversely affect flight addition undesirable ten dency turn can cause unexpected stalling one-half wing go about finding warped condition frequently-asked ques tions Check warps placing wing table preferably inverted trailing edge aimed eye level Close eye sighting along wing centerline distance about five feet compare trailing edge line wings lower surface An equal amount lower surface should visible both sides eye shifted wing half other Return gaze centerline make certain view line looking half Accuracy check creased raising trailing edge lowering eye until minimum amount lower surface visible warped wing quite easily discernible method well inequalities amount wash out feature intentionally built As gaze shifted wing center line toward tip trailing edge should appear lower near tip indicates amount washout both sides should visibly alike After sighting technique has acquired possible check warps washout holding wing arms length again wing held inverted sighting along centerline trailing edge Robart incidence meter will also detect warps Checking balance point quite sim ple first flights new model prefer balance point about 25o wing chord aft leading edge Looking down model ex act position lifting finger tips cant seen mark spots wings bottom surface bits mask ing tape near fuselage Now can slide finger tips rearward along bottom surface until tape felt lift model determine whether balances level tail droops down ward add nose weight Later after first flights some weight can removed shift balance point rear ward slightly necessary increase ele vator sensitivity Too much nose weight model tends nose over land ing aerobatic maneuverability suffers nose-heavy model will refuse spin Adding nose weight doesnt increase speed common myth Increased total weight means model will need ex tra speed takeoff As always eleva tor speed control Excessive nose weight will require up-elevator trim increases wing angle attack subsequent drag speed less up-trim actually increases angular dif ference between wing stabilizer ele vator incidences longitudinal dihedral true stabilizing influence makes model manageable pitch mode Too little nose weight tail-heavy model needs flown downelevator trim level flight reduces angular difference longi tudinal dihedral model becomes unstable pitch will constantly searching level flight its nose hunting upward downward Ryan SCW classic example type problem Twelve ounces lead nose converted wildcat pussycat could flown weight model needed constant attention no chance relax flying Control surface travel first flights should less rather Another myths about first flights have lots aileron travel prepare unexpected lateral instability no warps wing ailerons used small movements travel can less Too much aileron travel can lead tip stalls low speed Too little elevator travel isnt risky condition either balance point properly located need enough up-elevator get tail down landing aerobatics elevator travel can increased later Correction column April 1985 contains statement winning airplane LeBourget World Cham pionships last year landing gear retractable although should have letter David Dulaitis informs us prototype DH Drover fixed gear Actually should have known better notes made Paris during interview David Masterton specific Drover gear non-retractable Bonus points retract able landing gear arent necessary win ning championship News update letter Group Cap tain James Pelly-Fry England has brought news about steam-powered radio-controlled model built David Parker described January 1985 column Comet II proved aptly named late last summer being flown demonstration Westlands Aircraft Day everyones dismay caught fire airborne fell 134 Model Aviation Second Edition Most Complete Guide Market 167 Manufacturers Importers etc 250 Pages postage $165 Total Cost $860 Send *880 includes shipping UPS APO foreign surface maill $1245 foreign air mail Wu,f REP-UP Props Average laveatery DDD Prep! Due SD Sites Eve,ts New 4hout Custen Tuned Engines Coauhai Reciag Free Flight 5 Sport Ceaipetitiea Accessories 5 Parts Pyle Raciag Petter t S 0/C. Rage laveatory! Specialists l Caste Ce ZD 5 Reed Eagiaes Std 5 Rf C Caste Parts Ce Eagiaes Cemplete laveatory Dl ladividuel Stock Parts Fer Carreat 3D S Medalllea lagiacs Meay New Parts Disceatiaaed ce Eagines Rep/ku Orwick 2329 4nd 60 Engines lgaitiea fagie Accessories Vise 6 MasterCard Welcome Fer Detailed Drochare Sead 75E Nasteai Nreltsmeaship AD 263D Sagaaa Ni/Is CA D25 Ph 7113DS162 K~ - Hosted Indian City Radio Control Club Raffle Ready Fly GPM 540 CAP 21 Less Radio BY Great Planes Model Mfg Co Zenoah G 380 Engine World Engines K & B Super Poxy Finish BY K & B Manufacturing Inc DETROIT EXPO VII Greater Michigan Modelers Show Benjamin F Yack Recreation Center 3131 Third Street Wyandotte Michigan August 24 & 25 MANUFACTURERS STATIC DISPLAYS SWAP-SHOP CASH AWARDS OF SHOW FOR PLANES S e CARS TICS Auction C Refreshments C Free Parking un Luedeman 25505 Chernick Taylor Michigan 481 e 313 295-0569 ground burning pieces fluttering down Just like WW II movie well now James reports Davids post-mor tem revealed fuel pipe frac tured thus causing flames just intended damage surpris ingly bad would expect will live fly again Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53018 RC Electrics/Kopski Continued page 47 no need get inside plane get battery wiring unless course want remove/replace battery Since never remove/change packs field connector perfectly suited needs necessary cool battery model small blower since always take several planes out theres no need immediately replace pack anyway As noted photo two jacks three solder terminals used unused can nipped off normally route two charge-jack wires directly motor battery instead through switch harness arrangement although nothing wrong latter Astro systems uses male connector charger cords compact equally convenient use has two connec tions two-conductor cable connector parts good hundreds matings chargings finally wear out easily replaced low cost way charger cords white 18 gauge lamp cord like visibility grass field especially dusk Electric fliers also use fre quently-supplied two-prong plastic Molex connectors system wir ing charging connection well Personally view Molex-type connector best suited connec tions infrequently accessed such connecting motor switch harness thence battery like use connectors frequent connections such charging has experience Molex connector components fit very tightly new get rather flim sy after numerous uses have experi enced mechanical change signifi cant electrical contact deterioration through use well newer goldplated versions Astro may better last regard mechanical con sideration still remains So stallations may use Molex connectors basic wiring Switchcraft parts always used charging connection however some systems supplied ordinarily require use Molex connectors charg ing Two examples Astro 15 25 systems battery made up two six-packs two seven-packs its own connector indi vidual battery packs connected wiring harness turn wires series form 12- 14-cell batteries run larger motors charging pack disconnected charged indepedent smaller packsomething thats relatively easy 12 volt source like auto battery charger such Astros 4005D Dual Charger course refueling means dis connecting two Molex sets connecting two battery connectors two charging connections disconnecting charging complete reconnecting batteries harness Friends thats whole lotta Molex mating course requires some disassembly some part plane its hatch flight fly lot Id go back rubber hand-launch So what I use simple charging system modification extends its capabilities presented May June columns system concept simple addition Switchcraft jack wired combined 12- 14-cell battery packs plane allows charging batteries simple external connection No disassem bly No wear tear harness connectors flying less fooling around funand thats what hobby about Now want offer easily-assembled accessory can used charge systems device simple deedbeing nothing cable assembly allows previously-present ed systems used charge plane time can see photograph output-splitter low-cost easyto-assemble interconnecting harness use assembled plastic 35mm film container simple plastic housing will Try pill bottle idea use ability charge systems handle large numbers cells though large number may con tained plane cable shown simply connects twoplanes worth batteries series charge system same charge cur rent flows both batteries course total number cells cannot exceed capability charge system As operational example suppose have two planes having six-cell pack other seven-cell pack Ordinarily youd have charge time have two separate charg ers However packs same capacity ie cells same ampere-hour rating can simply connect charge system output cable output splitter input two inputs latter device July 1985 135
Edition: Model Aviation - 1985/07
Page Numbers: 44, 45, 131, 134, 135
Radio Control Scale Bob & Dolly Wischer FIBERGLASS over foam An engine cowl its compound curves con tinuously changing shape airplane part lends itself fiberglass-overfoam construction methods Blue styrene insulation foam used because easily cut formed has rigid cell structure white foam ordinarily used wing cores can sawed rough shape hand band circu lar saw circular saw can some what hazardous because fast-moving blade can melt foam causes seize blade violently sudden action can pull operators hand blade least troublesome method cutting foam electricallyheated nichrome wire Look Styro foam under Insulation Materials Yellow Pages find local supplier useful thickness foam sheet two inches permits foam core built up minimum number separate pieces Polygonal templates used foam-cutting guides hotwire method use /6- %2-in plywood guides can made stiff material wont ignite contact hot wire guides held manually both sides foam block hot wire cuts smoothly around peripheries make side blocks cowl form Two foam blocks can stacked both sides can cut operation desired four-inch total thickness about maximum can held average mans hand Top bottom blocks fill space between sides cut similar manner same ply guides used cut angles block ends match sides Foam blocks quickly assembled cementing four-minute epoxy maintain cowl shape meets fuselage front surface plywood former built cowl avoid problems warping plywood prefer laminate least two thick nesses ply former using white glue pressure C-clamps cowl shown photos former consists two laminations 3A2-in plywood Because difficulties have alignment fuselages past bulkheads now made process laminations sandwiched between %-in ply boards clamped glue dries Bulkheads gain enor mous strength come press abso lutely flat stay way outside shape former cut match fuselage front surface reduced size around its edge allow expected thickness fiberglass cloth resin applied later average cowl dimension could about 045 Y64 Adding three four layers fiberglass cloth over outside core will bring outer surface up fuselage dimensions Holes cut ply former clear engine muffler engine mounts throttle control few extra holes weight reduction 44 Model Aviation Bob going show us oasy make fiberglass-reInforced resin cowl starts L raw chunks blue styrene foam cuts using plywood templates hot wire Next R roughly-shaped foam blocks epoxied together plywood templates foreground likes blue foam because carveslsands easier has smoother surface Cowls laminated 6-ln plywood baokplate has cutouts clearance engine muffler 1 large round holes weight reduction Next Center ply backpiate spot-cemented foam core readiness shaping cowl fit side-mounted engine Finally R foam has carved sanded its exterior shape Styrofoam sands little effort make sure wear dust maskl Bob has little tips process column first layer fiberglass cloth being applied over foam core epoxy glue 1 Three layers will follow Once shell has completed Center foam chipped away interior p reparation mounting fuselagepositioned steel dowel p ins Finally R fiberglass cowl has sanded fine finIsh ready primer paint four-layer glass cowl exceptionally sturdy Note smoothly forward cutouts have finished assembled foam blocks spotcemented ply former again four-minute epoxy Carving foam rough shape done sharp knife used slicing action blue foam carves easily balsa Shaping foam its final form done No 60 aluminum oxide open-coat sandpaper over block operation must done care very easy remove too much foam especially corners polyester resin used bind layers fiberglass cloth foam must protected will dissolved resin Pores foam should filled generous coating vinyl spackling compound Sand smooth add another coat compound sure areas really covered Since want glass cloth come close contact plywood edge will maximum adhesion compound kept off plywood Scrape sand expose ply edge cowl using epoxy resin binder done cowl shown vinyl spackling coating required epoxy will attack styrene foam Some modelers using polyurethane foam cores fiberglass layups havent used material because preferred foam-cutting method hot wire have warnings about breathing fumes develop during cutting polyurethane foam cutting done saw knife sandpaper polyurethane foam has advantage affected polyester resin protecting layer vinyl spackle isnt needed curing processes polyester epoxy resins same cowl made polyester rock-hard ready sanding 24 hours epoxy takes twice long Polyester finishing resin sands fine powder mini mum effort regular resin used boats auto body repairs sands greater difficulty Epoxy resins come variety types some sand ease Hobbypoxy No 2 used sands well after about two days harden ing considerable effort needed epoxy-resin cowl will withstand much abuse nose-over landings cowls have made three four layers cloth long life greatest resistance fracture Allowing 045 buildup would require about four layers quick buildup use heavy six-ounce cloth first three layers follow top layer 2Y2-oz cloth has finer weave needs less primer smooth paint base weights mentioned square yard material six-ounce cloth forms around com pound curves difficulty Scissor cuts will permit some overlap curves lumps result removed coarse sandpaper before application successive layers Other irregularities due runs resin thickened spots also removed layer Excess cloth resin edges best removed just after resin sets up before hardens completely trick real labor-saver removal excess can toilsome later Hardened edges can also removed small circular saw Dremel grinder best primer paint adhesion remove gloss exterior surface sandpaper starting No 60 working up No 150 finer grades can used hardly worth ef fort because primer will fill small sand paper scratches As aspects Scale modeling sandpaper makes differ ence Dont waste time effort fine sandpaper except few final swipes smooth out scratches Coarse paper does heavy work level ing surface Sanding through top layer during leveling isnt catastrophic three layers remain underneath Ex tra primer spots sanded through will avoid visible weave showing through paint foam can now chipped out cowl interior Use handy tool such broad screwdriver blade cowls interior surface smoothed No 60 sandpaper engine-cooling hole cowl front cut Dremel Continued page 131 A. Yi iia THE WW II TRAINER Recreate excitement young USAAI pilots first experienced AT-6 No other militaty trainer has brought back fond memories During MN ii AT-6 irnvlwd training nearly pilot Imagine feeling freedom sense power made airplane famous NowCircus hobbies introduces flrstAT-6kitdesigned realistic four-cycle engines high quality balsa lilt will enjoy building well flying includes lots hardware accessories aluminum cowling realistic molded canopy along full-sized plans decal set Can bulltforfixed retractable landing gear includes landing flaps Get started first mission todayl Orders Toll Free Lf~J82-0022 Customer Service 702 732- 0022 $150 Circus Collection Catalog EU RUE UWJE EJE U mru IYA Specfficatlons Length 495 inches Wing span 725 inches Wing area 775 sq inches Weigtit 95-11 lbs Engine. 90 12 cu Four Cycle RadIo 5 6 channel Special INTRODUCTORY Combination AT-6 lUT Regularly $18995 OS EfIYA 120 Webra 91 Ibur Cycle Reg COMBO $52520 3132 South Highland Dr Las Vegas NV 89109 Kit $15995 Offer expires first month issue Limited quantity hand July1985 45 accidental engaging winch should foot switch left Weve photos winch/retriever combi nation come Tony Spetebroote Falmouth MI No details construc tion provided except say its easy move about retrieving portion unit works fine like Burts circuit designed safety mind eliminating foot switch Tony points out accidental turning winch practically eliminated uses knee activate unit claims excellent results Well whatever safety features read about use launching hardware system 200-meter band saw its running Keep safe Good lift Dan Pruss 131 E Pennington Ln Plainfield IL 60544 responding advertisers mention read about Model Aviation RC Scale/Wischers Continued page 45 grinder Robarts Rough Tough car bide cutters make short work job An alternate method drill row holes file through remaining material Final finishing hole done sandpaper wrapped around short lengths woOd dowel various diameters preferred locating method alignment between cowl fuselage front means three four steel dowel pins made short lengths R-in-diameter music wire Holes pins drilled cowl backplate formet before foam cemented place certain accurate registry Final sanding match cowl fuselage done pins place High spots sanded down until fingertips can feel no change level Low spots built up Sig Epoxolite Hobbypoxy Stuff dowel system two machine screws needed secure cowl can threaded convenient spot such front ends engine mounts Will fly fellow transmitter hands about fly first RC Scale model asks himself foregoing question pilot has some basic knowledge RC flying skills has reasonable success trainer types answer certainly affirmative Build ers Scale models kits magazine plans have reason assured airplane will perform satisfactory manner no special piloting skills essential assumes course model accurately constructed has correct control surface travel proper weight distribution no warps overweight Any faults can send model back workshop plastic bag Inaccuracies show up unexpected places Wing tail surface incidence angles should checked during construc tion Making changes angles after model completed means builder must cut finished surfaces wing stabilizer temporarily fastened position fuselage model set up flat surface measurements made fuselage referContinued page 134 July 1985 131 OPSs Little Pride Joys. modeler takes pride owning quality engine OPS offers Ursus 60 RC SLA 40 RC Both engines have ABC piston sleeves Schnuerle por& - dual ball bearings come OPS slide valve carb muffler Check out OPS engines local hobby shop have engine will proud own Parts People Post Office Box 26247 Orleans Louisiana 70186 242-5967 IN STOCK FOR IMMEDIATE SHIPMENT NEW RA 505$19995 New Onedro 39 CDI$10995 Reg Onadra3fi $9996 Brloigholloflywheol$11995 Re9 Qoodro 36 Power Aooewbly Only$6490 QUADRA REPAIR$1000 pine porte Jin Meoser ERCOUPEPLANS $2396 KIT $23995 Jin Meoner TOMAHAWKPLANS $2396 KIT $29996 Jiw Mooner 9BALL TRAINERPLANS $1996 KIT $19996 BALSA end BASSWOOD oil oboeSig pricee Ieee 10% Now ZENDAH G-23 $13996ZENOAN G39 $ 9996 FLOATS 3915 0001noree $1796cowplene kit $3996 FLOATS4914ecole noree $2196oowplene kit $4796 19 90W WHEELS 3995 P&W CVIS FLEET5$2596 PLANS SUPER STEARMAN 14 Godfrey$2995 STARDUSTER TOO 14 IBrieIgheIlo 13 J3 CUB Nelit$2995 VOLKSPLANE 13 Chicken ChorIle02395 COCKPIT KITS Towohnwk F4U1 Spitfire ME199$2395 Erneepo Fleet J3 Cob P95 P47 C 5091092195 Citebrie $2495 Zero $2995 Zero enferior$1095 US Doedro FUEL TANKS16 $99632 no $795 FIBERGLASSARROWSHAFTSB16n23long9$1996 24-Hour Service. Add $250 postage Send Bank Check Money Order JIM MESSERS QUALTIY MODEL PRODUCTS Valley View Dr. Boo 43 Allegeny NY 14706 M52LMP1000 $2500 ca includes shippIng UPS COD add $200 $600 plans CA add 6% Dealer Inquiries invited LINDSEY MICRO PRODUCTS 160-A No Fairview Ave SuIte 104 Goieta CA 93117 805 683 2042 After 5 pm PaCIfiC Both require TWO Channel Radio Mini Servos 250 MAH BATT wood construction include hardware needed Consumers Guide MA ISO Ott St Marrlsonburg VA 22801 Address RC Scale/Wischers Continued page 131 ence line leading trailing edges down surface certain agree construction drawings Robart incidence meter helpful time also desirable check horizontal alignment wing stabili zer measurements sighting rear sighting done dis tance about five eight feet viewing straight along fuselage centerline comparing distance stabilizer tip wings surface fin also checked certain truly vertical parallel fuselage warped wing will adversely affect flight addition undesirable ten dency turn can cause unexpected stalling one-half wing go about finding warped condition frequently-asked ques tions Check warps placing wing table preferably inverted trailing edge aimed eye level Close eye sighting along wing centerline distance about five feet compare trailing edge line wings lower surface An equal amount lower surface should visible both sides eye shifted wing half other Return gaze centerline make certain view line looking half Accuracy check creased raising trailing edge lowering eye until minimum amount lower surface visible warped wing quite easily discernible method well inequalities amount wash out feature intentionally built As gaze shifted wing center line toward tip trailing edge should appear lower near tip indicates amount washout both sides should visibly alike After sighting technique has acquired possible check warps washout holding wing arms length again wing held inverted sighting along centerline trailing edge Robart incidence meter will also detect warps Checking balance point quite sim ple first flights new model prefer balance point about 25o wing chord aft leading edge Looking down model ex act position lifting finger tips cant seen mark spots wings bottom surface bits mask ing tape near fuselage Now can slide finger tips rearward along bottom surface until tape felt lift model determine whether balances level tail droops down ward add nose weight Later after first flights some weight can removed shift balance point rear ward slightly necessary increase ele vator sensitivity Too much nose weight model tends nose over land ing aerobatic maneuverability suffers nose-heavy model will refuse spin Adding nose weight doesnt increase speed common myth Increased total weight means model will need ex tra speed takeoff As always eleva tor speed control Excessive nose weight will require up-elevator trim increases wing angle attack subsequent drag speed less up-trim actually increases angular dif ference between wing stabilizer ele vator incidences longitudinal dihedral true stabilizing influence makes model manageable pitch mode Too little nose weight tail-heavy model needs flown downelevator trim level flight reduces angular difference longi tudinal dihedral model becomes unstable pitch will constantly searching level flight its nose hunting upward downward Ryan SCW classic example type problem Twelve ounces lead nose converted wildcat pussycat could flown weight model needed constant attention no chance relax flying Control surface travel first flights should less rather Another myths about first flights have lots aileron travel prepare unexpected lateral instability no warps wing ailerons used small movements travel can less Too much aileron travel can lead tip stalls low speed Too little elevator travel isnt risky condition either balance point properly located need enough up-elevator get tail down landing aerobatics elevator travel can increased later Correction column April 1985 contains statement winning airplane LeBourget World Cham pionships last year landing gear retractable although should have letter David Dulaitis informs us prototype DH Drover fixed gear Actually should have known better notes made Paris during interview David Masterton specific Drover gear non-retractable Bonus points retract able landing gear arent necessary win ning championship News update letter Group Cap tain James Pelly-Fry England has brought news about steam-powered radio-controlled model built David Parker described January 1985 column Comet II proved aptly named late last summer being flown demonstration Westlands Aircraft Day everyones dismay caught fire airborne fell 134 Model Aviation Second Edition Most Complete Guide Market 167 Manufacturers Importers etc 250 Pages postage $165 Total Cost $860 Send *880 includes shipping UPS APO foreign surface maill $1245 foreign air mail Wu,f REP-UP Props Average laveatery DDD Prep! Due SD Sites Eve,ts New 4hout Custen Tuned Engines Coauhai Reciag Free Flight 5 Sport Ceaipetitiea Accessories 5 Parts Pyle Raciag Petter t S 0/C. Rage laveatory! Specialists l Caste Ce ZD 5 Reed Eagiaes Std 5 Rf C Caste Parts Ce Eagiaes Cemplete laveatory Dl ladividuel Stock Parts Fer Carreat 3D S Medalllea lagiacs Meay New Parts Disceatiaaed ce Eagines Rep/ku Orwick 2329 4nd 60 Engines lgaitiea fagie Accessories Vise 6 MasterCard Welcome Fer Detailed Drochare Sead 75E Nasteai Nreltsmeaship AD 263D Sagaaa Ni/Is CA D25 Ph 7113DS162 K~ - Hosted Indian City Radio Control Club Raffle Ready Fly GPM 540 CAP 21 Less Radio BY Great Planes Model Mfg Co Zenoah G 380 Engine World Engines K & B Super Poxy Finish BY K & B Manufacturing Inc DETROIT EXPO VII Greater Michigan Modelers Show Benjamin F Yack Recreation Center 3131 Third Street Wyandotte Michigan August 24 & 25 MANUFACTURERS STATIC DISPLAYS SWAP-SHOP CASH AWARDS OF SHOW FOR PLANES S e CARS TICS Auction C Refreshments C Free Parking un Luedeman 25505 Chernick Taylor Michigan 481 e 313 295-0569 ground burning pieces fluttering down Just like WW II movie well now James reports Davids post-mor tem revealed fuel pipe frac tured thus causing flames just intended damage surpris ingly bad would expect will live fly again Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53018 RC Electrics/Kopski Continued page 47 no need get inside plane get battery wiring unless course want remove/replace battery Since never remove/change packs field connector perfectly suited needs necessary cool battery model small blower since always take several planes out theres no need immediately replace pack anyway As noted photo two jacks three solder terminals used unused can nipped off normally route two charge-jack wires directly motor battery instead through switch harness arrangement although nothing wrong latter Astro systems uses male connector charger cords compact equally convenient use has two connec tions two-conductor cable connector parts good hundreds matings chargings finally wear out easily replaced low cost way charger cords white 18 gauge lamp cord like visibility grass field especially dusk Electric fliers also use fre quently-supplied two-prong plastic Molex connectors system wir ing charging connection well Personally view Molex-type connector best suited connec tions infrequently accessed such connecting motor switch harness thence battery like use connectors frequent connections such charging has experience Molex connector components fit very tightly new get rather flim sy after numerous uses have experi enced mechanical change signifi cant electrical contact deterioration through use well newer goldplated versions Astro may better last regard mechanical con sideration still remains So stallations may use Molex connectors basic wiring Switchcraft parts always used charging connection however some systems supplied ordinarily require use Molex connectors charg ing Two examples Astro 15 25 systems battery made up two six-packs two seven-packs its own connector indi vidual battery packs connected wiring harness turn wires series form 12- 14-cell batteries run larger motors charging pack disconnected charged indepedent smaller packsomething thats relatively easy 12 volt source like auto battery charger such Astros 4005D Dual Charger course refueling means dis connecting two Molex sets connecting two battery connectors two charging connections disconnecting charging complete reconnecting batteries harness Friends thats whole lotta Molex mating course requires some disassembly some part plane its hatch flight fly lot Id go back rubber hand-launch So what I use simple charging system modification extends its capabilities presented May June columns system concept simple addition Switchcraft jack wired combined 12- 14-cell battery packs plane allows charging batteries simple external connection No disassem bly No wear tear harness connectors flying less fooling around funand thats what hobby about Now want offer easily-assembled accessory can used charge systems device simple deedbeing nothing cable assembly allows previously-present ed systems used charge plane time can see photograph output-splitter low-cost easyto-assemble interconnecting harness use assembled plastic 35mm film container simple plastic housing will Try pill bottle idea use ability charge systems handle large numbers cells though large number may con tained plane cable shown simply connects twoplanes worth batteries series charge system same charge cur rent flows both batteries course total number cells cannot exceed capability charge system As operational example suppose have two planes having six-cell pack other seven-cell pack Ordinarily youd have charge time have two separate charg ers However packs same capacity ie cells same ampere-hour rating can simply connect charge system output cable output splitter input two inputs latter device July 1985 135
Edition: Model Aviation - 1985/07
Page Numbers: 44, 45, 131, 134, 135
Radio Control Scale Bob & Dolly Wischer FIBERGLASS over foam An engine cowl its compound curves con tinuously changing shape airplane part lends itself fiberglass-overfoam construction methods Blue styrene insulation foam used because easily cut formed has rigid cell structure white foam ordinarily used wing cores can sawed rough shape hand band circu lar saw circular saw can some what hazardous because fast-moving blade can melt foam causes seize blade violently sudden action can pull operators hand blade least troublesome method cutting foam electricallyheated nichrome wire Look Styro foam under Insulation Materials Yellow Pages find local supplier useful thickness foam sheet two inches permits foam core built up minimum number separate pieces Polygonal templates used foam-cutting guides hotwire method use /6- %2-in plywood guides can made stiff material wont ignite contact hot wire guides held manually both sides foam block hot wire cuts smoothly around peripheries make side blocks cowl form Two foam blocks can stacked both sides can cut operation desired four-inch total thickness about maximum can held average mans hand Top bottom blocks fill space between sides cut similar manner same ply guides used cut angles block ends match sides Foam blocks quickly assembled cementing four-minute epoxy maintain cowl shape meets fuselage front surface plywood former built cowl avoid problems warping plywood prefer laminate least two thick nesses ply former using white glue pressure C-clamps cowl shown photos former consists two laminations 3A2-in plywood Because difficulties have alignment fuselages past bulkheads now made process laminations sandwiched between %-in ply boards clamped glue dries Bulkheads gain enor mous strength come press abso lutely flat stay way outside shape former cut match fuselage front surface reduced size around its edge allow expected thickness fiberglass cloth resin applied later average cowl dimension could about 045 Y64 Adding three four layers fiberglass cloth over outside core will bring outer surface up fuselage dimensions Holes cut ply former clear engine muffler engine mounts throttle control few extra holes weight reduction 44 Model Aviation Bob going show us oasy make fiberglass-reInforced resin cowl starts L raw chunks blue styrene foam cuts using plywood templates hot wire Next R roughly-shaped foam blocks epoxied together plywood templates foreground likes blue foam because carveslsands easier has smoother surface Cowls laminated 6-ln plywood baokplate has cutouts clearance engine muffler 1 large round holes weight reduction Next Center ply backpiate spot-cemented foam core readiness shaping cowl fit side-mounted engine Finally R foam has carved sanded its exterior shape Styrofoam sands little effort make sure wear dust maskl Bob has little tips process column first layer fiberglass cloth being applied over foam core epoxy glue 1 Three layers will follow Once shell has completed Center foam chipped away interior p reparation mounting fuselagepositioned steel dowel p ins Finally R fiberglass cowl has sanded fine finIsh ready primer paint four-layer glass cowl exceptionally sturdy Note smoothly forward cutouts have finished assembled foam blocks spotcemented ply former again four-minute epoxy Carving foam rough shape done sharp knife used slicing action blue foam carves easily balsa Shaping foam its final form done No 60 aluminum oxide open-coat sandpaper over block operation must done care very easy remove too much foam especially corners polyester resin used bind layers fiberglass cloth foam must protected will dissolved resin Pores foam should filled generous coating vinyl spackling compound Sand smooth add another coat compound sure areas really covered Since want glass cloth come close contact plywood edge will maximum adhesion compound kept off plywood Scrape sand expose ply edge cowl using epoxy resin binder done cowl shown vinyl spackling coating required epoxy will attack styrene foam Some modelers using polyurethane foam cores fiberglass layups havent used material because preferred foam-cutting method hot wire have warnings about breathing fumes develop during cutting polyurethane foam cutting done saw knife sandpaper polyurethane foam has advantage affected polyester resin protecting layer vinyl spackle isnt needed curing processes polyester epoxy resins same cowl made polyester rock-hard ready sanding 24 hours epoxy takes twice long Polyester finishing resin sands fine powder mini mum effort regular resin used boats auto body repairs sands greater difficulty Epoxy resins come variety types some sand ease Hobbypoxy No 2 used sands well after about two days harden ing considerable effort needed epoxy-resin cowl will withstand much abuse nose-over landings cowls have made three four layers cloth long life greatest resistance fracture Allowing 045 buildup would require about four layers quick buildup use heavy six-ounce cloth first three layers follow top layer 2Y2-oz cloth has finer weave needs less primer smooth paint base weights mentioned square yard material six-ounce cloth forms around com pound curves difficulty Scissor cuts will permit some overlap curves lumps result removed coarse sandpaper before application successive layers Other irregularities due runs resin thickened spots also removed layer Excess cloth resin edges best removed just after resin sets up before hardens completely trick real labor-saver removal excess can toilsome later Hardened edges can also removed small circular saw Dremel grinder best primer paint adhesion remove gloss exterior surface sandpaper starting No 60 working up No 150 finer grades can used hardly worth ef fort because primer will fill small sand paper scratches As aspects Scale modeling sandpaper makes differ ence Dont waste time effort fine sandpaper except few final swipes smooth out scratches Coarse paper does heavy work level ing surface Sanding through top layer during leveling isnt catastrophic three layers remain underneath Ex tra primer spots sanded through will avoid visible weave showing through paint foam can now chipped out cowl interior Use handy tool such broad screwdriver blade cowls interior surface smoothed No 60 sandpaper engine-cooling hole cowl front cut Dremel Continued page 131 A. Yi iia THE WW II TRAINER Recreate excitement young USAAI pilots first experienced AT-6 No other militaty trainer has brought back fond memories During MN ii AT-6 irnvlwd training nearly pilot Imagine feeling freedom sense power made airplane famous NowCircus hobbies introduces flrstAT-6kitdesigned realistic four-cycle engines high quality balsa lilt will enjoy building well flying includes lots hardware accessories aluminum cowling realistic molded canopy along full-sized plans decal set Can bulltforfixed retractable landing gear includes landing flaps Get started first mission todayl Orders Toll Free Lf~J82-0022 Customer Service 702 732- 0022 $150 Circus Collection Catalog EU RUE UWJE EJE U mru IYA Specfficatlons Length 495 inches Wing span 725 inches Wing area 775 sq inches Weigtit 95-11 lbs Engine. 90 12 cu Four Cycle RadIo 5 6 channel Special INTRODUCTORY Combination AT-6 lUT Regularly $18995 OS EfIYA 120 Webra 91 Ibur Cycle Reg COMBO $52520 3132 South Highland Dr Las Vegas NV 89109 Kit $15995 Offer expires first month issue Limited quantity hand July1985 45 accidental engaging winch should foot switch left Weve photos winch/retriever combi nation come Tony Spetebroote Falmouth MI No details construc tion provided except say its easy move about retrieving portion unit works fine like Burts circuit designed safety mind eliminating foot switch Tony points out accidental turning winch practically eliminated uses knee activate unit claims excellent results Well whatever safety features read about use launching hardware system 200-meter band saw its running Keep safe Good lift Dan Pruss 131 E Pennington Ln Plainfield IL 60544 responding advertisers mention read about Model Aviation RC Scale/Wischers Continued page 45 grinder Robarts Rough Tough car bide cutters make short work job An alternate method drill row holes file through remaining material Final finishing hole done sandpaper wrapped around short lengths woOd dowel various diameters preferred locating method alignment between cowl fuselage front means three four steel dowel pins made short lengths R-in-diameter music wire Holes pins drilled cowl backplate formet before foam cemented place certain accurate registry Final sanding match cowl fuselage done pins place High spots sanded down until fingertips can feel no change level Low spots built up Sig Epoxolite Hobbypoxy Stuff dowel system two machine screws needed secure cowl can threaded convenient spot such front ends engine mounts Will fly fellow transmitter hands about fly first RC Scale model asks himself foregoing question pilot has some basic knowledge RC flying skills has reasonable success trainer types answer certainly affirmative Build ers Scale models kits magazine plans have reason assured airplane will perform satisfactory manner no special piloting skills essential assumes course model accurately constructed has correct control surface travel proper weight distribution no warps overweight Any faults can send model back workshop plastic bag Inaccuracies show up unexpected places Wing tail surface incidence angles should checked during construc tion Making changes angles after model completed means builder must cut finished surfaces wing stabilizer temporarily fastened position fuselage model set up flat surface measurements made fuselage referContinued page 134 July 1985 131 OPSs Little Pride Joys. modeler takes pride owning quality engine OPS offers Ursus 60 RC SLA 40 RC Both engines have ABC piston sleeves Schnuerle por& - dual ball bearings come OPS slide valve carb muffler Check out OPS engines local hobby shop have engine will proud own Parts People Post Office Box 26247 Orleans Louisiana 70186 242-5967 IN STOCK FOR IMMEDIATE SHIPMENT NEW RA 505$19995 New Onedro 39 CDI$10995 Reg Onadra3fi $9996 Brloigholloflywheol$11995 Re9 Qoodro 36 Power Aooewbly Only$6490 QUADRA REPAIR$1000 pine porte Jin Meoser ERCOUPEPLANS $2396 KIT $23995 Jin Meoner TOMAHAWKPLANS $2396 KIT $29996 Jiw Mooner 9BALL TRAINERPLANS $1996 KIT $19996 BALSA end BASSWOOD oil oboeSig pricee Ieee 10% Now ZENDAH G-23 $13996ZENOAN G39 $ 9996 FLOATS 3915 0001noree $1796cowplene kit $3996 FLOATS4914ecole noree $2196oowplene kit $4796 19 90W WHEELS 3995 P&W CVIS FLEET5$2596 PLANS SUPER STEARMAN 14 Godfrey$2995 STARDUSTER TOO 14 IBrieIgheIlo 13 J3 CUB Nelit$2995 VOLKSPLANE 13 Chicken ChorIle02395 COCKPIT KITS Towohnwk F4U1 Spitfire ME199$2395 Erneepo Fleet J3 Cob P95 P47 C 5091092195 Citebrie $2495 Zero $2995 Zero enferior$1095 US Doedro FUEL TANKS16 $99632 no $795 FIBERGLASSARROWSHAFTSB16n23long9$1996 24-Hour Service. Add $250 postage Send Bank Check Money Order JIM MESSERS QUALTIY MODEL PRODUCTS Valley View Dr. Boo 43 Allegeny NY 14706 M52LMP1000 $2500 ca includes shippIng UPS COD add $200 $600 plans CA add 6% Dealer Inquiries invited LINDSEY MICRO PRODUCTS 160-A No Fairview Ave SuIte 104 Goieta CA 93117 805 683 2042 After 5 pm PaCIfiC Both require TWO Channel Radio Mini Servos 250 MAH BATT wood construction include hardware needed Consumers Guide MA ISO Ott St Marrlsonburg VA 22801 Address RC Scale/Wischers Continued page 131 ence line leading trailing edges down surface certain agree construction drawings Robart incidence meter helpful time also desirable check horizontal alignment wing stabili zer measurements sighting rear sighting done dis tance about five eight feet viewing straight along fuselage centerline comparing distance stabilizer tip wings surface fin also checked certain truly vertical parallel fuselage warped wing will adversely affect flight addition undesirable ten dency turn can cause unexpected stalling one-half wing go about finding warped condition frequently-asked ques tions Check warps placing wing table preferably inverted trailing edge aimed eye level Close eye sighting along wing centerline distance about five feet compare trailing edge line wings lower surface An equal amount lower surface should visible both sides eye shifted wing half other Return gaze centerline make certain view line looking half Accuracy check creased raising trailing edge lowering eye until minimum amount lower surface visible warped wing quite easily discernible method well inequalities amount wash out feature intentionally built As gaze shifted wing center line toward tip trailing edge should appear lower near tip indicates amount washout both sides should visibly alike After sighting technique has acquired possible check warps washout holding wing arms length again wing held inverted sighting along centerline trailing edge Robart incidence meter will also detect warps Checking balance point quite sim ple first flights new model prefer balance point about 25o wing chord aft leading edge Looking down model ex act position lifting finger tips cant seen mark spots wings bottom surface bits mask ing tape near fuselage Now can slide finger tips rearward along bottom surface until tape felt lift model determine whether balances level tail droops down ward add nose weight Later after first flights some weight can removed shift balance point rear ward slightly necessary increase ele vator sensitivity Too much nose weight model tends nose over land ing aerobatic maneuverability suffers nose-heavy model will refuse spin Adding nose weight doesnt increase speed common myth Increased total weight means model will need ex tra speed takeoff As always eleva tor speed control Excessive nose weight will require up-elevator trim increases wing angle attack subsequent drag speed less up-trim actually increases angular dif ference between wing stabilizer ele vator incidences longitudinal dihedral true stabilizing influence makes model manageable pitch mode Too little nose weight tail-heavy model needs flown downelevator trim level flight reduces angular difference longi tudinal dihedral model becomes unstable pitch will constantly searching level flight its nose hunting upward downward Ryan SCW classic example type problem Twelve ounces lead nose converted wildcat pussycat could flown weight model needed constant attention no chance relax flying Control surface travel first flights should less rather Another myths about first flights have lots aileron travel prepare unexpected lateral instability no warps wing ailerons used small movements travel can less Too much aileron travel can lead tip stalls low speed Too little elevator travel isnt risky condition either balance point properly located need enough up-elevator get tail down landing aerobatics elevator travel can increased later Correction column April 1985 contains statement winning airplane LeBourget World Cham pionships last year landing gear retractable although should have letter David Dulaitis informs us prototype DH Drover fixed gear Actually should have known better notes made Paris during interview David Masterton specific Drover gear non-retractable Bonus points retract able landing gear arent necessary win ning championship News update letter Group Cap tain James Pelly-Fry England has brought news about steam-powered radio-controlled model built David Parker described January 1985 column Comet II proved aptly named late last summer being flown demonstration Westlands Aircraft Day everyones dismay caught fire airborne fell 134 Model Aviation Second Edition Most Complete Guide Market 167 Manufacturers Importers etc 250 Pages postage $165 Total Cost $860 Send *880 includes shipping UPS APO foreign surface maill $1245 foreign air mail Wu,f REP-UP Props Average laveatery DDD Prep! Due SD Sites Eve,ts New 4hout Custen Tuned Engines Coauhai Reciag Free Flight 5 Sport Ceaipetitiea Accessories 5 Parts Pyle Raciag Petter t S 0/C. Rage laveatory! Specialists l Caste Ce ZD 5 Reed Eagiaes Std 5 Rf C Caste Parts Ce Eagiaes Cemplete laveatory Dl ladividuel Stock Parts Fer Carreat 3D S Medalllea lagiacs Meay New Parts Disceatiaaed ce Eagines Rep/ku Orwick 2329 4nd 60 Engines lgaitiea fagie Accessories Vise 6 MasterCard Welcome Fer Detailed Drochare Sead 75E Nasteai Nreltsmeaship AD 263D Sagaaa Ni/Is CA D25 Ph 7113DS162 K~ - Hosted Indian City Radio Control Club Raffle Ready Fly GPM 540 CAP 21 Less Radio BY Great Planes Model Mfg Co Zenoah G 380 Engine World Engines K & B Super Poxy Finish BY K & B Manufacturing Inc DETROIT EXPO VII Greater Michigan Modelers Show Benjamin F Yack Recreation Center 3131 Third Street Wyandotte Michigan August 24 & 25 MANUFACTURERS STATIC DISPLAYS SWAP-SHOP CASH AWARDS OF SHOW FOR PLANES S e CARS TICS Auction C Refreshments C Free Parking un Luedeman 25505 Chernick Taylor Michigan 481 e 313 295-0569 ground burning pieces fluttering down Just like WW II movie well now James reports Davids post-mor tem revealed fuel pipe frac tured thus causing flames just intended damage surpris ingly bad would expect will live fly again Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53018 RC Electrics/Kopski Continued page 47 no need get inside plane get battery wiring unless course want remove/replace battery Since never remove/change packs field connector perfectly suited needs necessary cool battery model small blower since always take several planes out theres no need immediately replace pack anyway As noted photo two jacks three solder terminals used unused can nipped off normally route two charge-jack wires directly motor battery instead through switch harness arrangement although nothing wrong latter Astro systems uses male connector charger cords compact equally convenient use has two connec tions two-conductor cable connector parts good hundreds matings chargings finally wear out easily replaced low cost way charger cords white 18 gauge lamp cord like visibility grass field especially dusk Electric fliers also use fre quently-supplied two-prong plastic Molex connectors system wir ing charging connection well Personally view Molex-type connector best suited connec tions infrequently accessed such connecting motor switch harness thence battery like use connectors frequent connections such charging has experience Molex connector components fit very tightly new get rather flim sy after numerous uses have experi enced mechanical change signifi cant electrical contact deterioration through use well newer goldplated versions Astro may better last regard mechanical con sideration still remains So stallations may use Molex connectors basic wiring Switchcraft parts always used charging connection however some systems supplied ordinarily require use Molex connectors charg ing Two examples Astro 15 25 systems battery made up two six-packs two seven-packs its own connector indi vidual battery packs connected wiring harness turn wires series form 12- 14-cell batteries run larger motors charging pack disconnected charged indepedent smaller packsomething thats relatively easy 12 volt source like auto battery charger such Astros 4005D Dual Charger course refueling means dis connecting two Molex sets connecting two battery connectors two charging connections disconnecting charging complete reconnecting batteries harness Friends thats whole lotta Molex mating course requires some disassembly some part plane its hatch flight fly lot Id go back rubber hand-launch So what I use simple charging system modification extends its capabilities presented May June columns system concept simple addition Switchcraft jack wired combined 12- 14-cell battery packs plane allows charging batteries simple external connection No disassem bly No wear tear harness connectors flying less fooling around funand thats what hobby about Now want offer easily-assembled accessory can used charge systems device simple deedbeing nothing cable assembly allows previously-present ed systems used charge plane time can see photograph output-splitter low-cost easyto-assemble interconnecting harness use assembled plastic 35mm film container simple plastic housing will Try pill bottle idea use ability charge systems handle large numbers cells though large number may con tained plane cable shown simply connects twoplanes worth batteries series charge system same charge cur rent flows both batteries course total number cells cannot exceed capability charge system As operational example suppose have two planes having six-cell pack other seven-cell pack Ordinarily youd have charge time have two separate charg ers However packs same capacity ie cells same ampere-hour rating can simply connect charge system output cable output splitter input two inputs latter device July 1985 135
Edition: Model Aviation - 1985/07
Page Numbers: 44, 45, 131, 134, 135
Radio Control Scale Bob & Dolly Wischer FIBERGLASS over foam An engine cowl its compound curves con tinuously changing shape airplane part lends itself fiberglass-overfoam construction methods Blue styrene insulation foam used because easily cut formed has rigid cell structure white foam ordinarily used wing cores can sawed rough shape hand band circu lar saw circular saw can some what hazardous because fast-moving blade can melt foam causes seize blade violently sudden action can pull operators hand blade least troublesome method cutting foam electricallyheated nichrome wire Look Styro foam under Insulation Materials Yellow Pages find local supplier useful thickness foam sheet two inches permits foam core built up minimum number separate pieces Polygonal templates used foam-cutting guides hotwire method use /6- %2-in plywood guides can made stiff material wont ignite contact hot wire guides held manually both sides foam block hot wire cuts smoothly around peripheries make side blocks cowl form Two foam blocks can stacked both sides can cut operation desired four-inch total thickness about maximum can held average mans hand Top bottom blocks fill space between sides cut similar manner same ply guides used cut angles block ends match sides Foam blocks quickly assembled cementing four-minute epoxy maintain cowl shape meets fuselage front surface plywood former built cowl avoid problems warping plywood prefer laminate least two thick nesses ply former using white glue pressure C-clamps cowl shown photos former consists two laminations 3A2-in plywood Because difficulties have alignment fuselages past bulkheads now made process laminations sandwiched between %-in ply boards clamped glue dries Bulkheads gain enor mous strength come press abso lutely flat stay way outside shape former cut match fuselage front surface reduced size around its edge allow expected thickness fiberglass cloth resin applied later average cowl dimension could about 045 Y64 Adding three four layers fiberglass cloth over outside core will bring outer surface up fuselage dimensions Holes cut ply former clear engine muffler engine mounts throttle control few extra holes weight reduction 44 Model Aviation Bob going show us oasy make fiberglass-reInforced resin cowl starts L raw chunks blue styrene foam cuts using plywood templates hot wire Next R roughly-shaped foam blocks epoxied together plywood templates foreground likes blue foam because carveslsands easier has smoother surface Cowls laminated 6-ln plywood baokplate has cutouts clearance engine muffler 1 large round holes weight reduction Next Center ply backpiate spot-cemented foam core readiness shaping cowl fit side-mounted engine Finally R foam has carved sanded its exterior shape Styrofoam sands little effort make sure wear dust maskl Bob has little tips process column first layer fiberglass cloth being applied over foam core epoxy glue 1 Three layers will follow Once shell has completed Center foam chipped away interior p reparation mounting fuselagepositioned steel dowel p ins Finally R fiberglass cowl has sanded fine finIsh ready primer paint four-layer glass cowl exceptionally sturdy Note smoothly forward cutouts have finished assembled foam blocks spotcemented ply former again four-minute epoxy Carving foam rough shape done sharp knife used slicing action blue foam carves easily balsa Shaping foam its final form done No 60 aluminum oxide open-coat sandpaper over block operation must done care very easy remove too much foam especially corners polyester resin used bind layers fiberglass cloth foam must protected will dissolved resin Pores foam should filled generous coating vinyl spackling compound Sand smooth add another coat compound sure areas really covered Since want glass cloth come close contact plywood edge will maximum adhesion compound kept off plywood Scrape sand expose ply edge cowl using epoxy resin binder done cowl shown vinyl spackling coating required epoxy will attack styrene foam Some modelers using polyurethane foam cores fiberglass layups havent used material because preferred foam-cutting method hot wire have warnings about breathing fumes develop during cutting polyurethane foam cutting done saw knife sandpaper polyurethane foam has advantage affected polyester resin protecting layer vinyl spackle isnt needed curing processes polyester epoxy resins same cowl made polyester rock-hard ready sanding 24 hours epoxy takes twice long Polyester finishing resin sands fine powder mini mum effort regular resin used boats auto body repairs sands greater difficulty Epoxy resins come variety types some sand ease Hobbypoxy No 2 used sands well after about two days harden ing considerable effort needed epoxy-resin cowl will withstand much abuse nose-over landings cowls have made three four layers cloth long life greatest resistance fracture Allowing 045 buildup would require about four layers quick buildup use heavy six-ounce cloth first three layers follow top layer 2Y2-oz cloth has finer weave needs less primer smooth paint base weights mentioned square yard material six-ounce cloth forms around com pound curves difficulty Scissor cuts will permit some overlap curves lumps result removed coarse sandpaper before application successive layers Other irregularities due runs resin thickened spots also removed layer Excess cloth resin edges best removed just after resin sets up before hardens completely trick real labor-saver removal excess can toilsome later Hardened edges can also removed small circular saw Dremel grinder best primer paint adhesion remove gloss exterior surface sandpaper starting No 60 working up No 150 finer grades can used hardly worth ef fort because primer will fill small sand paper scratches As aspects Scale modeling sandpaper makes differ ence Dont waste time effort fine sandpaper except few final swipes smooth out scratches Coarse paper does heavy work level ing surface Sanding through top layer during leveling isnt catastrophic three layers remain underneath Ex tra primer spots sanded through will avoid visible weave showing through paint foam can now chipped out cowl interior Use handy tool such broad screwdriver blade cowls interior surface smoothed No 60 sandpaper engine-cooling hole cowl front cut Dremel Continued page 131 A. Yi iia THE WW II TRAINER Recreate excitement young USAAI pilots first experienced AT-6 No other militaty trainer has brought back fond memories During MN ii AT-6 irnvlwd training nearly pilot Imagine feeling freedom sense power made airplane famous NowCircus hobbies introduces flrstAT-6kitdesigned realistic four-cycle engines high quality balsa lilt will enjoy building well flying includes lots hardware accessories aluminum cowling realistic molded canopy along full-sized plans decal set Can bulltforfixed retractable landing gear includes landing flaps Get started first mission todayl Orders Toll Free Lf~J82-0022 Customer Service 702 732- 0022 $150 Circus Collection Catalog EU RUE UWJE EJE U mru IYA Specfficatlons Length 495 inches Wing span 725 inches Wing area 775 sq inches Weigtit 95-11 lbs Engine. 90 12 cu Four Cycle RadIo 5 6 channel Special INTRODUCTORY Combination AT-6 lUT Regularly $18995 OS EfIYA 120 Webra 91 Ibur Cycle Reg COMBO $52520 3132 South Highland Dr Las Vegas NV 89109 Kit $15995 Offer expires first month issue Limited quantity hand July1985 45 accidental engaging winch should foot switch left Weve photos winch/retriever combi nation come Tony Spetebroote Falmouth MI No details construc tion provided except say its easy move about retrieving portion unit works fine like Burts circuit designed safety mind eliminating foot switch Tony points out accidental turning winch practically eliminated uses knee activate unit claims excellent results Well whatever safety features read about use launching hardware system 200-meter band saw its running Keep safe Good lift Dan Pruss 131 E Pennington Ln Plainfield IL 60544 responding advertisers mention read about Model Aviation RC Scale/Wischers Continued page 45 grinder Robarts Rough Tough car bide cutters make short work job An alternate method drill row holes file through remaining material Final finishing hole done sandpaper wrapped around short lengths woOd dowel various diameters preferred locating method alignment between cowl fuselage front means three four steel dowel pins made short lengths R-in-diameter music wire Holes pins drilled cowl backplate formet before foam cemented place certain accurate registry Final sanding match cowl fuselage done pins place High spots sanded down until fingertips can feel no change level Low spots built up Sig Epoxolite Hobbypoxy Stuff dowel system two machine screws needed secure cowl can threaded convenient spot such front ends engine mounts Will fly fellow transmitter hands about fly first RC Scale model asks himself foregoing question pilot has some basic knowledge RC flying skills has reasonable success trainer types answer certainly affirmative Build ers Scale models kits magazine plans have reason assured airplane will perform satisfactory manner no special piloting skills essential assumes course model accurately constructed has correct control surface travel proper weight distribution no warps overweight Any faults can send model back workshop plastic bag Inaccuracies show up unexpected places Wing tail surface incidence angles should checked during construc tion Making changes angles after model completed means builder must cut finished surfaces wing stabilizer temporarily fastened position fuselage model set up flat surface measurements made fuselage referContinued page 134 July 1985 131 OPSs Little Pride Joys. modeler takes pride owning quality engine OPS offers Ursus 60 RC SLA 40 RC Both engines have ABC piston sleeves Schnuerle por& - dual ball bearings come OPS slide valve carb muffler Check out OPS engines local hobby shop have engine will proud own Parts People Post Office Box 26247 Orleans Louisiana 70186 242-5967 IN STOCK FOR IMMEDIATE SHIPMENT NEW RA 505$19995 New Onedro 39 CDI$10995 Reg Onadra3fi $9996 Brloigholloflywheol$11995 Re9 Qoodro 36 Power Aooewbly Only$6490 QUADRA REPAIR$1000 pine porte Jin Meoser ERCOUPEPLANS $2396 KIT $23995 Jin Meoner TOMAHAWKPLANS $2396 KIT $29996 Jiw Mooner 9BALL TRAINERPLANS $1996 KIT $19996 BALSA end BASSWOOD oil oboeSig pricee Ieee 10% Now ZENDAH G-23 $13996ZENOAN G39 $ 9996 FLOATS 3915 0001noree $1796cowplene kit $3996 FLOATS4914ecole noree $2196oowplene kit $4796 19 90W WHEELS 3995 P&W CVIS FLEET5$2596 PLANS SUPER STEARMAN 14 Godfrey$2995 STARDUSTER TOO 14 IBrieIgheIlo 13 J3 CUB Nelit$2995 VOLKSPLANE 13 Chicken ChorIle02395 COCKPIT KITS Towohnwk F4U1 Spitfire ME199$2395 Erneepo Fleet J3 Cob P95 P47 C 5091092195 Citebrie $2495 Zero $2995 Zero enferior$1095 US Doedro FUEL TANKS16 $99632 no $795 FIBERGLASSARROWSHAFTSB16n23long9$1996 24-Hour Service. Add $250 postage Send Bank Check Money Order JIM MESSERS QUALTIY MODEL PRODUCTS Valley View Dr. Boo 43 Allegeny NY 14706 M52LMP1000 $2500 ca includes shippIng UPS COD add $200 $600 plans CA add 6% Dealer Inquiries invited LINDSEY MICRO PRODUCTS 160-A No Fairview Ave SuIte 104 Goieta CA 93117 805 683 2042 After 5 pm PaCIfiC Both require TWO Channel Radio Mini Servos 250 MAH BATT wood construction include hardware needed Consumers Guide MA ISO Ott St Marrlsonburg VA 22801 Address RC Scale/Wischers Continued page 131 ence line leading trailing edges down surface certain agree construction drawings Robart incidence meter helpful time also desirable check horizontal alignment wing stabili zer measurements sighting rear sighting done dis tance about five eight feet viewing straight along fuselage centerline comparing distance stabilizer tip wings surface fin also checked certain truly vertical parallel fuselage warped wing will adversely affect flight addition undesirable ten dency turn can cause unexpected stalling one-half wing go about finding warped condition frequently-asked ques tions Check warps placing wing table preferably inverted trailing edge aimed eye level Close eye sighting along wing centerline distance about five feet compare trailing edge line wings lower surface An equal amount lower surface should visible both sides eye shifted wing half other Return gaze centerline make certain view line looking half Accuracy check creased raising trailing edge lowering eye until minimum amount lower surface visible warped wing quite easily discernible method well inequalities amount wash out feature intentionally built As gaze shifted wing center line toward tip trailing edge should appear lower near tip indicates amount washout both sides should visibly alike After sighting technique has acquired possible check warps washout holding wing arms length again wing held inverted sighting along centerline trailing edge Robart incidence meter will also detect warps Checking balance point quite sim ple first flights new model prefer balance point about 25o wing chord aft leading edge Looking down model ex act position lifting finger tips cant seen mark spots wings bottom surface bits mask ing tape near fuselage Now can slide finger tips rearward along bottom surface until tape felt lift model determine whether balances level tail droops down ward add nose weight Later after first flights some weight can removed shift balance point rear ward slightly necessary increase ele vator sensitivity Too much nose weight model tends nose over land ing aerobatic maneuverability suffers nose-heavy model will refuse spin Adding nose weight doesnt increase speed common myth Increased total weight means model will need ex tra speed takeoff As always eleva tor speed control Excessive nose weight will require up-elevator trim increases wing angle attack subsequent drag speed less up-trim actually increases angular dif ference between wing stabilizer ele vator incidences longitudinal dihedral true stabilizing influence makes model manageable pitch mode Too little nose weight tail-heavy model needs flown downelevator trim level flight reduces angular difference longi tudinal dihedral model becomes unstable pitch will constantly searching level flight its nose hunting upward downward Ryan SCW classic example type problem Twelve ounces lead nose converted wildcat pussycat could flown weight model needed constant attention no chance relax flying Control surface travel first flights should less rather Another myths about first flights have lots aileron travel prepare unexpected lateral instability no warps wing ailerons used small movements travel can less Too much aileron travel can lead tip stalls low speed Too little elevator travel isnt risky condition either balance point properly located need enough up-elevator get tail down landing aerobatics elevator travel can increased later Correction column April 1985 contains statement winning airplane LeBourget World Cham pionships last year landing gear retractable although should have letter David Dulaitis informs us prototype DH Drover fixed gear Actually should have known better notes made Paris during interview David Masterton specific Drover gear non-retractable Bonus points retract able landing gear arent necessary win ning championship News update letter Group Cap tain James Pelly-Fry England has brought news about steam-powered radio-controlled model built David Parker described January 1985 column Comet II proved aptly named late last summer being flown demonstration Westlands Aircraft Day everyones dismay caught fire airborne fell 134 Model Aviation Second Edition Most Complete Guide Market 167 Manufacturers Importers etc 250 Pages postage $165 Total Cost $860 Send *880 includes shipping UPS APO foreign surface maill $1245 foreign air mail Wu,f REP-UP Props Average laveatery DDD Prep! Due SD Sites Eve,ts New 4hout Custen Tuned Engines Coauhai Reciag Free Flight 5 Sport Ceaipetitiea Accessories 5 Parts Pyle Raciag Petter t S 0/C. Rage laveatory! Specialists l Caste Ce ZD 5 Reed Eagiaes Std 5 Rf C Caste Parts Ce Eagiaes Cemplete laveatory Dl ladividuel Stock Parts Fer Carreat 3D S Medalllea lagiacs Meay New Parts Disceatiaaed ce Eagines Rep/ku Orwick 2329 4nd 60 Engines lgaitiea fagie Accessories Vise 6 MasterCard Welcome Fer Detailed Drochare Sead 75E Nasteai Nreltsmeaship AD 263D Sagaaa Ni/Is CA D25 Ph 7113DS162 K~ - Hosted Indian City Radio Control Club Raffle Ready Fly GPM 540 CAP 21 Less Radio BY Great Planes Model Mfg Co Zenoah G 380 Engine World Engines K & B Super Poxy Finish BY K & B Manufacturing Inc DETROIT EXPO VII Greater Michigan Modelers Show Benjamin F Yack Recreation Center 3131 Third Street Wyandotte Michigan August 24 & 25 MANUFACTURERS STATIC DISPLAYS SWAP-SHOP CASH AWARDS OF SHOW FOR PLANES S e CARS TICS Auction C Refreshments C Free Parking un Luedeman 25505 Chernick Taylor Michigan 481 e 313 295-0569 ground burning pieces fluttering down Just like WW II movie well now James reports Davids post-mor tem revealed fuel pipe frac tured thus causing flames just intended damage surpris ingly bad would expect will live fly again Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53018 RC Electrics/Kopski Continued page 47 no need get inside plane get battery wiring unless course want remove/replace battery Since never remove/change packs field connector perfectly suited needs necessary cool battery model small blower since always take several planes out theres no need immediately replace pack anyway As noted photo two jacks three solder terminals used unused can nipped off normally route two charge-jack wires directly motor battery instead through switch harness arrangement although nothing wrong latter Astro systems uses male connector charger cords compact equally convenient use has two connec tions two-conductor cable connector parts good hundreds matings chargings finally wear out easily replaced low cost way charger cords white 18 gauge lamp cord like visibility grass field especially dusk Electric fliers also use fre quently-supplied two-prong plastic Molex connectors system wir ing charging connection well Personally view Molex-type connector best suited connec tions infrequently accessed such connecting motor switch harness thence battery like use connectors frequent connections such charging has experience Molex connector components fit very tightly new get rather flim sy after numerous uses have experi enced mechanical change signifi cant electrical contact deterioration through use well newer goldplated versions Astro may better last regard mechanical con sideration still remains So stallations may use Molex connectors basic wiring Switchcraft parts always used charging connection however some systems supplied ordinarily require use Molex connectors charg ing Two examples Astro 15 25 systems battery made up two six-packs two seven-packs its own connector indi vidual battery packs connected wiring harness turn wires series form 12- 14-cell batteries run larger motors charging pack disconnected charged indepedent smaller packsomething thats relatively easy 12 volt source like auto battery charger such Astros 4005D Dual Charger course refueling means dis connecting two Molex sets connecting two battery connectors two charging connections disconnecting charging complete reconnecting batteries harness Friends thats whole lotta Molex mating course requires some disassembly some part plane its hatch flight fly lot Id go back rubber hand-launch So what I use simple charging system modification extends its capabilities presented May June columns system concept simple addition Switchcraft jack wired combined 12- 14-cell battery packs plane allows charging batteries simple external connection No disassem bly No wear tear harness connectors flying less fooling around funand thats what hobby about Now want offer easily-assembled accessory can used charge systems device simple deedbeing nothing cable assembly allows previously-present ed systems used charge plane time can see photograph output-splitter low-cost easyto-assemble interconnecting harness use assembled plastic 35mm film container simple plastic housing will Try pill bottle idea use ability charge systems handle large numbers cells though large number may con tained plane cable shown simply connects twoplanes worth batteries series charge system same charge cur rent flows both batteries course total number cells cannot exceed capability charge system As operational example suppose have two planes having six-cell pack other seven-cell pack Ordinarily youd have charge time have two separate charg ers However packs same capacity ie cells same ampere-hour rating can simply connect charge system output cable output splitter input two inputs latter device July 1985 135
Edition: Model Aviation - 1985/07
Page Numbers: 44, 45, 131, 134, 135
Radio Control Scale Bob & Dolly Wischer FIBERGLASS over foam An engine cowl its compound curves con tinuously changing shape airplane part lends itself fiberglass-overfoam construction methods Blue styrene insulation foam used because easily cut formed has rigid cell structure white foam ordinarily used wing cores can sawed rough shape hand band circu lar saw circular saw can some what hazardous because fast-moving blade can melt foam causes seize blade violently sudden action can pull operators hand blade least troublesome method cutting foam electricallyheated nichrome wire Look Styro foam under Insulation Materials Yellow Pages find local supplier useful thickness foam sheet two inches permits foam core built up minimum number separate pieces Polygonal templates used foam-cutting guides hotwire method use /6- %2-in plywood guides can made stiff material wont ignite contact hot wire guides held manually both sides foam block hot wire cuts smoothly around peripheries make side blocks cowl form Two foam blocks can stacked both sides can cut operation desired four-inch total thickness about maximum can held average mans hand Top bottom blocks fill space between sides cut similar manner same ply guides used cut angles block ends match sides Foam blocks quickly assembled cementing four-minute epoxy maintain cowl shape meets fuselage front surface plywood former built cowl avoid problems warping plywood prefer laminate least two thick nesses ply former using white glue pressure C-clamps cowl shown photos former consists two laminations 3A2-in plywood Because difficulties have alignment fuselages past bulkheads now made process laminations sandwiched between %-in ply boards clamped glue dries Bulkheads gain enor mous strength come press abso lutely flat stay way outside shape former cut match fuselage front surface reduced size around its edge allow expected thickness fiberglass cloth resin applied later average cowl dimension could about 045 Y64 Adding three four layers fiberglass cloth over outside core will bring outer surface up fuselage dimensions Holes cut ply former clear engine muffler engine mounts throttle control few extra holes weight reduction 44 Model Aviation Bob going show us oasy make fiberglass-reInforced resin cowl starts L raw chunks blue styrene foam cuts using plywood templates hot wire Next R roughly-shaped foam blocks epoxied together plywood templates foreground likes blue foam because carveslsands easier has smoother surface Cowls laminated 6-ln plywood baokplate has cutouts clearance engine muffler 1 large round holes weight reduction Next Center ply backpiate spot-cemented foam core readiness shaping cowl fit side-mounted engine Finally R foam has carved sanded its exterior shape Styrofoam sands little effort make sure wear dust maskl Bob has little tips process column first layer fiberglass cloth being applied over foam core epoxy glue 1 Three layers will follow Once shell has completed Center foam chipped away interior p reparation mounting fuselagepositioned steel dowel p ins Finally R fiberglass cowl has sanded fine finIsh ready primer paint four-layer glass cowl exceptionally sturdy Note smoothly forward cutouts have finished assembled foam blocks spotcemented ply former again four-minute epoxy Carving foam rough shape done sharp knife used slicing action blue foam carves easily balsa Shaping foam its final form done No 60 aluminum oxide open-coat sandpaper over block operation must done care very easy remove too much foam especially corners polyester resin used bind layers fiberglass cloth foam must protected will dissolved resin Pores foam should filled generous coating vinyl spackling compound Sand smooth add another coat compound sure areas really covered Since want glass cloth come close contact plywood edge will maximum adhesion compound kept off plywood Scrape sand expose ply edge cowl using epoxy resin binder done cowl shown vinyl spackling coating required epoxy will attack styrene foam Some modelers using polyurethane foam cores fiberglass layups havent used material because preferred foam-cutting method hot wire have warnings about breathing fumes develop during cutting polyurethane foam cutting done saw knife sandpaper polyurethane foam has advantage affected polyester resin protecting layer vinyl spackle isnt needed curing processes polyester epoxy resins same cowl made polyester rock-hard ready sanding 24 hours epoxy takes twice long Polyester finishing resin sands fine powder mini mum effort regular resin used boats auto body repairs sands greater difficulty Epoxy resins come variety types some sand ease Hobbypoxy No 2 used sands well after about two days harden ing considerable effort needed epoxy-resin cowl will withstand much abuse nose-over landings cowls have made three four layers cloth long life greatest resistance fracture Allowing 045 buildup would require about four layers quick buildup use heavy six-ounce cloth first three layers follow top layer 2Y2-oz cloth has finer weave needs less primer smooth paint base weights mentioned square yard material six-ounce cloth forms around com pound curves difficulty Scissor cuts will permit some overlap curves lumps result removed coarse sandpaper before application successive layers Other irregularities due runs resin thickened spots also removed layer Excess cloth resin edges best removed just after resin sets up before hardens completely trick real labor-saver removal excess can toilsome later Hardened edges can also removed small circular saw Dremel grinder best primer paint adhesion remove gloss exterior surface sandpaper starting No 60 working up No 150 finer grades can used hardly worth ef fort because primer will fill small sand paper scratches As aspects Scale modeling sandpaper makes differ ence Dont waste time effort fine sandpaper except few final swipes smooth out scratches Coarse paper does heavy work level ing surface Sanding through top layer during leveling isnt catastrophic three layers remain underneath Ex tra primer spots sanded through will avoid visible weave showing through paint foam can now chipped out cowl interior Use handy tool such broad screwdriver blade cowls interior surface smoothed No 60 sandpaper engine-cooling hole cowl front cut Dremel Continued page 131 A. Yi iia THE WW II TRAINER Recreate excitement young USAAI pilots first experienced AT-6 No other militaty trainer has brought back fond memories During MN ii AT-6 irnvlwd training nearly pilot Imagine feeling freedom sense power made airplane famous NowCircus hobbies introduces flrstAT-6kitdesigned realistic four-cycle engines high quality balsa lilt will enjoy building well flying includes lots hardware accessories aluminum cowling realistic molded canopy along full-sized plans decal set Can bulltforfixed retractable landing gear includes landing flaps Get started first mission todayl Orders Toll Free Lf~J82-0022 Customer Service 702 732- 0022 $150 Circus Collection Catalog EU RUE UWJE EJE U mru IYA Specfficatlons Length 495 inches Wing span 725 inches Wing area 775 sq inches Weigtit 95-11 lbs Engine. 90 12 cu Four Cycle RadIo 5 6 channel Special INTRODUCTORY Combination AT-6 lUT Regularly $18995 OS EfIYA 120 Webra 91 Ibur Cycle Reg COMBO $52520 3132 South Highland Dr Las Vegas NV 89109 Kit $15995 Offer expires first month issue Limited quantity hand July1985 45 accidental engaging winch should foot switch left Weve photos winch/retriever combi nation come Tony Spetebroote Falmouth MI No details construc tion provided except say its easy move about retrieving portion unit works fine like Burts circuit designed safety mind eliminating foot switch Tony points out accidental turning winch practically eliminated uses knee activate unit claims excellent results Well whatever safety features read about use launching hardware system 200-meter band saw its running Keep safe Good lift Dan Pruss 131 E Pennington Ln Plainfield IL 60544 responding advertisers mention read about Model Aviation RC Scale/Wischers Continued page 45 grinder Robarts Rough Tough car bide cutters make short work job An alternate method drill row holes file through remaining material Final finishing hole done sandpaper wrapped around short lengths woOd dowel various diameters preferred locating method alignment between cowl fuselage front means three four steel dowel pins made short lengths R-in-diameter music wire Holes pins drilled cowl backplate formet before foam cemented place certain accurate registry Final sanding match cowl fuselage done pins place High spots sanded down until fingertips can feel no change level Low spots built up Sig Epoxolite Hobbypoxy Stuff dowel system two machine screws needed secure cowl can threaded convenient spot such front ends engine mounts Will fly fellow transmitter hands about fly first RC Scale model asks himself foregoing question pilot has some basic knowledge RC flying skills has reasonable success trainer types answer certainly affirmative Build ers Scale models kits magazine plans have reason assured airplane will perform satisfactory manner no special piloting skills essential assumes course model accurately constructed has correct control surface travel proper weight distribution no warps overweight Any faults can send model back workshop plastic bag Inaccuracies show up unexpected places Wing tail surface incidence angles should checked during construc tion Making changes angles after model completed means builder must cut finished surfaces wing stabilizer temporarily fastened position fuselage model set up flat surface measurements made fuselage referContinued page 134 July 1985 131 OPSs Little Pride Joys. modeler takes pride owning quality engine OPS offers Ursus 60 RC SLA 40 RC Both engines have ABC piston sleeves Schnuerle por& - dual ball bearings come OPS slide valve carb muffler Check out OPS engines local hobby shop have engine will proud own Parts People Post Office Box 26247 Orleans Louisiana 70186 242-5967 IN STOCK FOR IMMEDIATE SHIPMENT NEW RA 505$19995 New Onedro 39 CDI$10995 Reg Onadra3fi $9996 Brloigholloflywheol$11995 Re9 Qoodro 36 Power Aooewbly Only$6490 QUADRA REPAIR$1000 pine porte Jin Meoser ERCOUPEPLANS $2396 KIT $23995 Jin Meoner TOMAHAWKPLANS $2396 KIT $29996 Jiw Mooner 9BALL TRAINERPLANS $1996 KIT $19996 BALSA end BASSWOOD oil oboeSig pricee Ieee 10% Now ZENDAH G-23 $13996ZENOAN G39 $ 9996 FLOATS 3915 0001noree $1796cowplene kit $3996 FLOATS4914ecole noree $2196oowplene kit $4796 19 90W WHEELS 3995 P&W CVIS FLEET5$2596 PLANS SUPER STEARMAN 14 Godfrey$2995 STARDUSTER TOO 14 IBrieIgheIlo 13 J3 CUB Nelit$2995 VOLKSPLANE 13 Chicken ChorIle02395 COCKPIT KITS Towohnwk F4U1 Spitfire ME199$2395 Erneepo Fleet J3 Cob P95 P47 C 5091092195 Citebrie $2495 Zero $2995 Zero enferior$1095 US Doedro FUEL TANKS16 $99632 no $795 FIBERGLASSARROWSHAFTSB16n23long9$1996 24-Hour Service. Add $250 postage Send Bank Check Money Order JIM MESSERS QUALTIY MODEL PRODUCTS Valley View Dr. Boo 43 Allegeny NY 14706 M52LMP1000 $2500 ca includes shippIng UPS COD add $200 $600 plans CA add 6% Dealer Inquiries invited LINDSEY MICRO PRODUCTS 160-A No Fairview Ave SuIte 104 Goieta CA 93117 805 683 2042 After 5 pm PaCIfiC Both require TWO Channel Radio Mini Servos 250 MAH BATT wood construction include hardware needed Consumers Guide MA ISO Ott St Marrlsonburg VA 22801 Address RC Scale/Wischers Continued page 131 ence line leading trailing edges down surface certain agree construction drawings Robart incidence meter helpful time also desirable check horizontal alignment wing stabili zer measurements sighting rear sighting done dis tance about five eight feet viewing straight along fuselage centerline comparing distance stabilizer tip wings surface fin also checked certain truly vertical parallel fuselage warped wing will adversely affect flight addition undesirable ten dency turn can cause unexpected stalling one-half wing go about finding warped condition frequently-asked ques tions Check warps placing wing table preferably inverted trailing edge aimed eye level Close eye sighting along wing centerline distance about five feet compare trailing edge line wings lower surface An equal amount lower surface should visible both sides eye shifted wing half other Return gaze centerline make certain view line looking half Accuracy check creased raising trailing edge lowering eye until minimum amount lower surface visible warped wing quite easily discernible method well inequalities amount wash out feature intentionally built As gaze shifted wing center line toward tip trailing edge should appear lower near tip indicates amount washout both sides should visibly alike After sighting technique has acquired possible check warps washout holding wing arms length again wing held inverted sighting along centerline trailing edge Robart incidence meter will also detect warps Checking balance point quite sim ple first flights new model prefer balance point about 25o wing chord aft leading edge Looking down model ex act position lifting finger tips cant seen mark spots wings bottom surface bits mask ing tape near fuselage Now can slide finger tips rearward along bottom surface until tape felt lift model determine whether balances level tail droops down ward add nose weight Later after first flights some weight can removed shift balance point rear ward slightly necessary increase ele vator sensitivity Too much nose weight model tends nose over land ing aerobatic maneuverability suffers nose-heavy model will refuse spin Adding nose weight doesnt increase speed common myth Increased total weight means model will need ex tra speed takeoff As always eleva tor speed control Excessive nose weight will require up-elevator trim increases wing angle attack subsequent drag speed less up-trim actually increases angular dif ference between wing stabilizer ele vator incidences longitudinal dihedral true stabilizing influence makes model manageable pitch mode Too little nose weight tail-heavy model needs flown downelevator trim level flight reduces angular difference longi tudinal dihedral model becomes unstable pitch will constantly searching level flight its nose hunting upward downward Ryan SCW classic example type problem Twelve ounces lead nose converted wildcat pussycat could flown weight model needed constant attention no chance relax flying Control surface travel first flights should less rather Another myths about first flights have lots aileron travel prepare unexpected lateral instability no warps wing ailerons used small movements travel can less Too much aileron travel can lead tip stalls low speed Too little elevator travel isnt risky condition either balance point properly located need enough up-elevator get tail down landing aerobatics elevator travel can increased later Correction column April 1985 contains statement winning airplane LeBourget World Cham pionships last year landing gear retractable although should have letter David Dulaitis informs us prototype DH Drover fixed gear Actually should have known better notes made Paris during interview David Masterton specific Drover gear non-retractable Bonus points retract able landing gear arent necessary win ning championship News update letter Group Cap tain James Pelly-Fry England has brought news about steam-powered radio-controlled model built David Parker described January 1985 column Comet II proved aptly named late last summer being flown demonstration Westlands Aircraft Day everyones dismay caught fire airborne fell 134 Model Aviation Second Edition Most Complete Guide Market 167 Manufacturers Importers etc 250 Pages postage $165 Total Cost $860 Send *880 includes shipping UPS APO foreign surface maill $1245 foreign air mail Wu,f REP-UP Props Average laveatery DDD Prep! Due SD Sites Eve,ts New 4hout Custen Tuned Engines Coauhai Reciag Free Flight 5 Sport Ceaipetitiea Accessories 5 Parts Pyle Raciag Petter t S 0/C. Rage laveatory! Specialists l Caste Ce ZD 5 Reed Eagiaes Std 5 Rf C Caste Parts Ce Eagiaes Cemplete laveatory Dl ladividuel Stock Parts Fer Carreat 3D S Medalllea lagiacs Meay New Parts Disceatiaaed ce Eagines Rep/ku Orwick 2329 4nd 60 Engines lgaitiea fagie Accessories Vise 6 MasterCard Welcome Fer Detailed Drochare Sead 75E Nasteai Nreltsmeaship AD 263D Sagaaa Ni/Is CA D25 Ph 7113DS162 K~ - Hosted Indian City Radio Control Club Raffle Ready Fly GPM 540 CAP 21 Less Radio BY Great Planes Model Mfg Co Zenoah G 380 Engine World Engines K & B Super Poxy Finish BY K & B Manufacturing Inc DETROIT EXPO VII Greater Michigan Modelers Show Benjamin F Yack Recreation Center 3131 Third Street Wyandotte Michigan August 24 & 25 MANUFACTURERS STATIC DISPLAYS SWAP-SHOP CASH AWARDS OF SHOW FOR PLANES S e CARS TICS Auction C Refreshments C Free Parking un Luedeman 25505 Chernick Taylor Michigan 481 e 313 295-0569 ground burning pieces fluttering down Just like WW II movie well now James reports Davids post-mor tem revealed fuel pipe frac tured thus causing flames just intended damage surpris ingly bad would expect will live fly again Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53018 RC Electrics/Kopski Continued page 47 no need get inside plane get battery wiring unless course want remove/replace battery Since never remove/change packs field connector perfectly suited needs necessary cool battery model small blower since always take several planes out theres no need immediately replace pack anyway As noted photo two jacks three solder terminals used unused can nipped off normally route two charge-jack wires directly motor battery instead through switch harness arrangement although nothing wrong latter Astro systems uses male connector charger cords compact equally convenient use has two connec tions two-conductor cable connector parts good hundreds matings chargings finally wear out easily replaced low cost way charger cords white 18 gauge lamp cord like visibility grass field especially dusk Electric fliers also use fre quently-supplied two-prong plastic Molex connectors system wir ing charging connection well Personally view Molex-type connector best suited connec tions infrequently accessed such connecting motor switch harness thence battery like use connectors frequent connections such charging has experience Molex connector components fit very tightly new get rather flim sy after numerous uses have experi enced mechanical change signifi cant electrical contact deterioration through use well newer goldplated versions Astro may better last regard mechanical con sideration still remains So stallations may use Molex connectors basic wiring Switchcraft parts always used charging connection however some systems supplied ordinarily require use Molex connectors charg ing Two examples Astro 15 25 systems battery made up two six-packs two seven-packs its own connector indi vidual battery packs connected wiring harness turn wires series form 12- 14-cell batteries run larger motors charging pack disconnected charged indepedent smaller packsomething thats relatively easy 12 volt source like auto battery charger such Astros 4005D Dual Charger course refueling means dis connecting two Molex sets connecting two battery connectors two charging connections disconnecting charging complete reconnecting batteries harness Friends thats whole lotta Molex mating course requires some disassembly some part plane its hatch flight fly lot Id go back rubber hand-launch So what I use simple charging system modification extends its capabilities presented May June columns system concept simple addition Switchcraft jack wired combined 12- 14-cell battery packs plane allows charging batteries simple external connection No disassem bly No wear tear harness connectors flying less fooling around funand thats what hobby about Now want offer easily-assembled accessory can used charge systems device simple deedbeing nothing cable assembly allows previously-present ed systems used charge plane time can see photograph output-splitter low-cost easyto-assemble interconnecting harness use assembled plastic 35mm film container simple plastic housing will Try pill bottle idea use ability charge systems handle large numbers cells though large number may con tained plane cable shown simply connects twoplanes worth batteries series charge system same charge cur rent flows both batteries course total number cells cannot exceed capability charge system As operational example suppose have two planes having six-cell pack other seven-cell pack Ordinarily youd have charge time have two separate charg ers However packs same capacity ie cells same ampere-hour rating can simply connect charge system output cable output splitter input two inputs latter device July 1985 135