i IL ill U Planked Lockheed Vega one-inch scale shows half shell carrying tail wheel fin supports projects Ned uses owndesigned pylon control arms monofila ment cables running buried surface actu ation mechanisms discernible insert photo FULL-scale stressed skin aircraft have built plywood sheet metal recently fiberglass Sheet shell structures very efficient used reason well obtaining smooth aerodynamic surfaces Shells always lightest structures since thinnest usable material may produce structure much stronger needed account framed structures may best small aircraft Shells function hollow beams depend shape strength stiffness Failure results because local crumpling rupture bend soda straw other paper tube will fail collapsing places wings fuselages ribs rings stiffeners prevent Drawing upon intimate knowledge both full-scale modeling structures author gives us some exciting new ways beat old gameand must plank much improved method tooE Ned Kragness 32 Model Aviation gb stress member/ landing gear center section struts- .--.-- I-- ----~- --- LI--K -- N r . / fattest section Start zone Tern orar brace Top Fig 1Overlapping adjacent skins compound curves coupled judicious sanding approaches real aircraft engineering Wider cross-section skins overlap both ends others end Above Fig 2Precutting planks youll have study text has numerous advantages chief dont end up bunch wildly tapered conventional planks delay such collapse Doublers used increase thickness local high loads structural efficiency scale appearance shells would desirable model structures have much used however because construction difficulties seem too great Occa sional carved hollowed blocks once seen balsa blocks become expensive large sizes small components can still use technique particularly curvature abrupt such engine cowls tailcones transition pieces two broad geometric classes such shells Both classes usually found somewhere aircraft depending structural needs aerodynamic considerations first class curvature character developable means cut along straight line along simple curve resulting shape can unrolled flat sheet common Luscombe fuselage undevelopable sheet second class nondevelopable compound curvature best exemplified egg ball no cut can made will permit us flatten its skin surface shrinking stretch ing tearing skin material non-uniform manner Most aircraft compound forms ap proximated number non-compound curves As familiar example consider common world globe made up number printed flat gores Full-size aircraft usually exploit trick will return later Shell Fuselage Construction Metal plywood skinned fuselage hull structures difficult model compound curvatures must built least attractive method used very light models involves stringers bulkheads covered tissue silk plastic film stringer remains clearly visible will least some bulkhead edges Another method heavier better appearance involves plank ing over bulkheads sanding rough exterior smooth contour finish sophisti cated approaches molding plastics can yield realistic heavier structures Molding May 1980 33 Navion shell showing false structure hold shell alignment until two halves cemented together Scale one-inch plastics however involves making molds different technique producing shells has worked out depends flexibility balsa bending parallel its grain also depends fact full-scale aircraft appear display compound curvatures actually composed simple curves assembled together compound curves individual sheet can same thing examine drawings photographs can frequently discern full-scale aircraft seg mentation simply-curved wrapped sheet reach ing bulkhead former next either forward aft take Henschel HS 126 fuselage shown immediately apparent cockpit zone side sheets could easily installed buckling However leaves problem manage apparent compound curvatures ward aft remember series connecting short straight lines can look like curve particularly short-line pieces small angles can divide shell segments join small angles start fattest pair bulkheads place skin panel extendpast both bulkheads least 3/16 inch Under overhand will cement strip strip will now provide joining surface next skin panels fore aft will turn extend past its next bulkhead process can repeated procedure thus carried both fore aft alternation permitting work panel preceding dries place progressing structure should appear shown drawing now delighted can produce shell what other structural considera tions should like such reinforcements such things landing gear struts engine mounts Concentrated loads must diffused shells landing gear strut must fastened fuselage ring stiffener bulkhead loads spread out local fracture will occur necessary plan ahead install strut mounts blocks whatever bulkhead stringer assembly before skinning As first efforts created complete fuselage before realized mounting members cabane struts would problem relatively easy however add internal sheet lamination beams doublers before shell halves cemented together Local increases skin thickness also often desirable however joint technique de scribed far above does permit direct joining dissimilar thicknesses can done setting joining strip down amount desired thickness increase panel joined make transition 1/32 skin 1/16 necessary install joining strip before trimming already installed skin panel edge trimming thickened edge finally installing actual joining strip course makes first strip spacer Preliminary Planning Choose drawings have reasonably accurate cross sections outlines first trial method avoid aircraft elaborate fillets between wing fuselage tail fuselage drawings produce exact size layout fuselage side view cross sections will need sheet balsa bulkheads skin light fuselage structure rubber power smaller 049 power approximately 24 30 inches long will mean 1/16 bulkheads 1/32 skin shell built two halves con structed side top-view layouts important building surface flat because halfshells will too stiff allow springing forcing together Construction First make upper lower keels 1/16 sheet either cutting contour orby bending fuselage side view has strip 34 Model Aviation Seen both inside outside shell Sections Vega skin 1/16 balsa sheet Before joining author installs control mechanisms similar real aircraft Two halves P-51 Mustang shell ready forjoin ing rigid accurate no monkey business force fitting Navion shells matched cementedheld together rubber bands Interior details yet installed Edges simulated metal skin pieces show clearlywill later invisible outline about 3/16 wide Pin drawing board top wax paper-protected drawing cross sections bulkheads carefully cut 1/16 sheet two halves right left half fuselage begun notching set bulkheads keel strips cementing exactly spaced vertical keel members Take special care bulkheads accurately located perpendicular surface Use temporary bracing necessary Once done use straight wood strip check fair lines run length structure strip touches bulkhead edge Correct errors both bulkhead halves before proceeding Either sand edge away add thin padding strip bring bulkhead Out proper fairing Choose largest bulkhead pair cut paper skin wrap outline piece other over bulkhead shown drawing Fig 1 skin panel cut sheet stock grain running fore aft no require ment panel reach top keel bottom may applied two pieces Refer Fig 1 appearance skin panel precautionary notes skin panel secure dry will obvious must now make neat joint between panels lie fore aft accomplished joining strips cut grain running along short dimension strip strips provide gluing shelf described earlier stress carrying members will found some joining strips may need some surface sanding allow its next sheet panel set well sanding can done emery board affects next gluing surface tilting toward next bulkhead use short thin straightedge piece card shelf next bulkhead should contact between straightedge shelf across shelf permits next skin panel cemented voids cement joint single remaining requirement means providing neat skin joint line will found necessary curve forward rear edge skin panel secure neat seam Several strips thin card stock cut very gently curving edges choosing strip appropriate curvature wrapping along edge skin panel place proper edge curvature can found same card strip used Out line cut edge next panel added edge installed panel also prepared way before lengths joining strip cemented its overhanging edge skin thickness changes both installed skin its underlying first shelf must crisply cut Actual working techniques simple can developed experience first fuselage suggested plan make three halves rejecting either first worst Balsa skin stock should C cut will bend easily splitting Ambroid cement Duco other solvent softenable glues used possible use solvent remove poor appearing panels disrupting good ones Hot Stuff Tite Bond other nonsoftenable cements used own better sure before gluing several cautions have nonflat building board will forced sand joining surfaces both halves expect squeeze half shells mate wont deform large pressures fracture 2 should plan bulkheads interior structure accept large loads come wing landing gear etc share skin over reasonably large areas too typical full scale practice 3 can make progressive changes skin thickness front rear strength requirements dictate 4 rigid half shells allow interior installations bulkhead lightening before joining 5 Cock pits wheel wells other large openings must have edge support framing doublers 6 Excess skin thickness can removed sanding desired Lets review what has discussed add some other ideas will helpful Determine exact location extra thick ness skin panels make suitable notations side view Stiffeners reinforcing members should also planned time 2 cross sections keel members should trimmed away allow thickness skin cross sections should also made right left hand halves exactly alike some will receive such loads should close enough other straight lines between pair will approximate Continued page 106 May 1980 35 iwo exampies us rignier-sype sneiis assemuied internal control mechanisms installed Seversky Republic P-35 left German Henschel HS-1 26 right Vuiree u i-i srieem iusewge briell wiui .arveu visible Ned mounts surfaces Ia full scale abhors crude lviii ISUIIIIUI iIlei.naUi suns uarely type horns rods devises reverse too After steps will line again no adverse effects except its back wards stock point system can assembled Make pushrods paying special attention Y pushrod connects two pitch belicranks together Shape shown Figure 2 check smooth operation ranges collective pitch Put extra ball back swash plate can snap antirotation link original arrangement can used although presently using pin slot combination similar found Alouette few closing notesthe screws holding plastic angle bearings tend hit aluminum bracket other side servo plate pushed through Take Moto-Tool grind away aluminum nuts can installed easily need four angle bearings high style Two provided kit Orderpart #3503 other two front pushrod runs straight through lower front aluminum bracket Roughly pencil area rod runs cut portion out sufficient clearance rod pass through swash plate bend IN STOCK FOR IMMEDIATE SHIPMENT QUADRAS QUADRA REPAIR- $1000 plus parts Jim Messers ERCOUPE KIT- $1950O Concepts BIG FLEET KIT- $17995* Barkleys TIGER MOTH KIT- $24995* *inCludes FREE Du-Bro Wheels -SCALE PLANS FOR QUADRA ERCOUPE SKYBOLT- $2000 ea SUPER STEARMAN- $2495 ZINGER & TOP FLITE PROPS- 10% off BALSA & SPRUCE sizes- 45% off COCKPIT KIT Ercoupe- $1500 Stearman $1800 Fleet- $1800 RADIAL ENGINESfor Fleet- $3000 COVER ITE 15 rolls - 20% off 24-Hour Service $200 postage Send Bank Check Money Order JIM MESSERS QUALITY MODEL PRODUCTS 106 Valley View DrAllegany NY 14706 rods bellcranks swash plate Everything works perfectly smooth straight rods straight strong latter step illustrated article hover hinge plate should parallel wooden servo plate Also bellcranks reinforced style should used top bellcranks lead servo arms should shortened 4 mm see Figure 3 foregoing material will enable alleviate problems might have swash plate control systems Kavan Jet Ranger welcome comments questions might have address Ray Hostetler Box 136 Kidron OH 44636 Phone 2 16-8578393 first RC Helicopter Olympics will held Vista CA June 681980 Olympic theme will held throughout contest gold silver bronze medals awarded manufacturers will donate products awards also expected include kits radios etc Compe tition will grouped three classes Nov ice Intermediate Expert Novice fliers can look forward such tasks balloon busting pylon racing limbo others never having leave hovering mode Intermediate Expert filers will put out fires rescue people burning buildings participate drag races looping lim bos will also separate free-style events class separate awards given winners continuous clinic will available modeler has questions about set-up flying RC helicopter 1980 RC Helicopter Olympics de signed around Schluter Helicopter Party concept pilots can have fun instead entering grueling contest-like competition past Entertainment planned Saturday June 6 form banquet dinner guest speaker telling about history RC helicopter Films other enjoyable activities also planned Sponsors event North County Blade Busters Contest Director Bob Robeson 173 Sunset Drive No 2 Vista CA 92083 Telephone enquiries handled Charlie Onstott 714 744-9605 Thats month Dont forget pre flight checks Fly safely Dave Chesney Rt 9 Box 621A Greensboro NC 27409 Shell Game/Kragness continued page 35 curve fuselage other words greater curvature closer bulkheads 3 side view drawing must sharply drawn drawing must translucent paper accurately duplicated right left hand sure make fuselage right left half shell 4 Use bulkheads feel desirable much regard weight considerable amount weight can deleted bulkheads cut away narrow half rings just prior final joining two halfshells non-major bulkheads cut-away may extend skin joining strips 5 will find considerable accuracy desirable exact location bulkheads keel strips squareness drawing work board holding keel strips solidly work board surface 6 best gluing clamp final joining strip rubber wound spirally around two halves lightest tension will bring good contact good idea make completely closed shells make cut outs cockpits etc later 7 Some practice experimenting will allow improve technique curious e HS-l 26 shell shown weighs 17 ounces 18 inches long primarily 1/32 skin over 1/16 bulkheads 14 X 1/16 side stringer strip Planked Shells shapes yield best planking Most what said about concen trated loads also applies planked shells As example will discuss Lockheed Vega Orion Sirius Altair etc photos show 1/12-scale model constructed 1/16 planking fuselage geometry totally symmetrical divided cut along horizontal center plane both top bottom identical cut vertical plane right left half shells identical Lockheed Vega fuselage wood molding using two identical shells laminated glue pressed concrete mold 106 Model Aviation REALISMSCALE ACCESSORIES Y WILLIAMS BROTHERS RADIO CONTROL SCALE PILOTS E WHEELS CONTROL-LINECYLINDERS ENGINE KITS MACHINE GUN KITS FREE-FLIGHT STIC DISPLAY MODELS SEND 5Ot FOR COMPLETE ILLUSTRATED CATALOG DEPT MA 181 PAWNEE STREET SAN MARCOS CA 0 92069 JLLA iI2LINc F@RECATOR MOLD YOUR OWN PARTS FOR PLANES BOATS CARS ETC w -w $4995 Instructions assembly & use included $39 Includes A8St Pack ABS ID PREPAID dealer order directUS ONLY Vacuum former plastics Easyto make own Cowls wheel pants Canopies etc works home oven hose type vacuum Cleaner Qualified Dealer Inquiries Invited PLA8TICBuIk Packs ABS PI.tjo Sheet Fornicede sheets 8th 17 Packs Only PCSPACK THICKNESSPER PACKPRICE 0201/50 500 030 1/32 00 045 3/64 00 0601/16 00 090 3/32 00 AssortmentPack see below1500 Asofln, PerkeerIe/os 0-020/4-030/3- 040 2 060/ Sod 1050 shelr doe perk $1500 soOn, ordered ,itl th* FOr,icror AlAS ned/tn Over 3 lbs per pock Idea Development Inc Box 7399 rk Delaware 19711 AEROBATIC AIRPLANES BY ROST C MORRISON .I IS SUPERB DRAWINGS 8395 PLUS ..L SOW POSTA~ CATALOGS ~k-TECN III $100Ocean rule Ken riwy VIOA CR6005 60466 shell skin varying thickness being thicker front landing gear wing engine imposed large loads assembled shells reinforced internal rings longitudinals joined together produce alight strong efficient fuselage good fuselage shell could molded same way would require far too much work making mold reinforcing shells Planking reasonable choice will bit differently however relying less thick balsa technique will start repeating some shell techniques steps already described first step produce side view accurate cross sections stress location such wing spar firewall landing gear attach ment stations Other intermediate cross sections will needed produce good form perhaps reinforce hand-launching grip zone Set up top bottom outline strips drawing erect half bulkheads just done sheet shell assembly Again accurate bulkhead edges will meet join shells mated together Since both halves should identical will use fairing strips find contour changes corrections needed half bulkheads first half shell will correct other halves match Now lay single 16 stringer front rear along hori zontal outer belt line should notch flush bulkheads problem planking fuselage boat hull planks must narrower get smaller sections boat builder has technique calls spilingused establish taper necessary Spiling would very difficult tedious model work tackle problem another way need make long gently-curved taper planks allow change fuselage circum ference will cut curves straightedge Four 1/16 highjigging blocks will cemented cutting board 5/16 X 1/16 strip forced curve blocks straight line cut will become curve strip allowed unbend straight cut made blade several degrees off vertical will bevel edge curved edge can assist getting good edge joint Fig 1 shows layout ofjigging blocks used 1/12 scale Lockheed Vega largest semi-circumference fuselage example 5 expect use -wide planks will 20 planks required However small end has semi-circumference 1 planks must taper 1/16 wide end arithmetic useful accuracy size up producing perfect matching will still have make adjustment last two planks Proceed center line belt line stringer making sure no cement squeezeout interfere next plank Add plank side belt line alternating above below watching progress covering shell fore aft will probably necessary change block spacing cutting jig adjust plank taper final plank does perfectly fill remaining gap top bottom stringer dont worry three-quarters skin place shell can lifted off board tailored plank can placed Lucky 14/Zawada continued page 39 well large propellerseven 11 12 inches diameter use old type Palmer 4-ounce tank pressure silencerthe orifice about 1/16 tank inch deep fuel pick center mounted about 1/16 above spray bar engine Thanks engine runs little faster inverted flight helps little some maneuvers Flying first few flights should made calm light wind regulate height fuel-tank placement spray bar engine speed model straight flight maneuvers different props model must fly slowly lap times around 56 seconds 67-ft lines lap times inverted flight around 54 seconds engine runs must maximum model flies upward two cycle must change runs quickly four cycles model flies downward regulate leadout lines best point during square maneuvers Future Plans course 1980 World Championships Poland next model Lucky 15 1979 season hope will luckier still being made similar dimensions Lucky 14 new airfoil sections own design greater maximum thickness because model will powered 5T46 include airfoil sections plan tail plane will made like tail plane Stiletto 660 Les McDonald stab covered 1/16 balsa Ifyou should have questions ideas about Lucky 14 feel free write care editor CL Aerobatics/Paul continued page 40 founding father Aero Modelers Association Northern California later became WAMWestern Associated Modelers wrote up new set rules Stunt basically same rules being used Northern California occurred fall 1948 early 1949 Accordingto correspondence Roy Mayes little foggy dates much correspondence records 40s destroyed fire Regardless whether new pattern first used 1948 49 Roy introduced some new ideas 1 eight-minute time limit 2 three attempts make two official flights 3 old controversial item appearance points 4 flight pattern points WAM appearance points quite heavy could amount something like 25% total score Roy explained appearance points letters After seeing old time free flight gas models changed semi-realistic models thingies same thing happening Round-the-Pole race cars determined keep same thing happening control line 1949 rules included following sequence starting takeoff level flight climb dive wingover five consecutive inside lpsfive con secutive outside 1oops inverted flight three horizontal figure eights vertical figure eight overhead figure eight square 1oop special ma neuver must described detail judges prior flight landing Appearance points 8 80 1951 special maneuver dropped pattern Otherwise pattern same 51 52 5 l-52 pattern used time old time stunt According rule book 1953 pattern 108 Model Aviation *A COLORFUL * t ** * R AIRPLANE KIT * * Contents4 oIotuI Sheets4-Desians *Folding ineiroctions sWoights Send $200 Pius 50$ Postage Check MO pa Kit laBs 23 wks deliesni HEF Enterprise 7118 Sse,nit Rd. DaIenIII50559
Edition: Model Aviation - 1980/05
Page Numbers: 32, 33, 34, 35, 106, 108
i IL ill U Planked Lockheed Vega one-inch scale shows half shell carrying tail wheel fin supports projects Ned uses owndesigned pylon control arms monofila ment cables running buried surface actu ation mechanisms discernible insert photo FULL-scale stressed skin aircraft have built plywood sheet metal recently fiberglass Sheet shell structures very efficient used reason well obtaining smooth aerodynamic surfaces Shells always lightest structures since thinnest usable material may produce structure much stronger needed account framed structures may best small aircraft Shells function hollow beams depend shape strength stiffness Failure results because local crumpling rupture bend soda straw other paper tube will fail collapsing places wings fuselages ribs rings stiffeners prevent Drawing upon intimate knowledge both full-scale modeling structures author gives us some exciting new ways beat old gameand must plank much improved method tooE Ned Kragness 32 Model Aviation gb stress member/ landing gear center section struts- .--.-- I-- ----~- --- LI--K -- N r . / fattest section Start zone Tern orar brace Top Fig 1Overlapping adjacent skins compound curves coupled judicious sanding approaches real aircraft engineering Wider cross-section skins overlap both ends others end Above Fig 2Precutting planks youll have study text has numerous advantages chief dont end up bunch wildly tapered conventional planks delay such collapse Doublers used increase thickness local high loads structural efficiency scale appearance shells would desirable model structures have much used however because construction difficulties seem too great Occa sional carved hollowed blocks once seen balsa blocks become expensive large sizes small components can still use technique particularly curvature abrupt such engine cowls tailcones transition pieces two broad geometric classes such shells Both classes usually found somewhere aircraft depending structural needs aerodynamic considerations first class curvature character developable means cut along straight line along simple curve resulting shape can unrolled flat sheet common Luscombe fuselage undevelopable sheet second class nondevelopable compound curvature best exemplified egg ball no cut can made will permit us flatten its skin surface shrinking stretch ing tearing skin material non-uniform manner Most aircraft compound forms ap proximated number non-compound curves As familiar example consider common world globe made up number printed flat gores Full-size aircraft usually exploit trick will return later Shell Fuselage Construction Metal plywood skinned fuselage hull structures difficult model compound curvatures must built least attractive method used very light models involves stringers bulkheads covered tissue silk plastic film stringer remains clearly visible will least some bulkhead edges Another method heavier better appearance involves plank ing over bulkheads sanding rough exterior smooth contour finish sophisti cated approaches molding plastics can yield realistic heavier structures Molding May 1980 33 Navion shell showing false structure hold shell alignment until two halves cemented together Scale one-inch plastics however involves making molds different technique producing shells has worked out depends flexibility balsa bending parallel its grain also depends fact full-scale aircraft appear display compound curvatures actually composed simple curves assembled together compound curves individual sheet can same thing examine drawings photographs can frequently discern full-scale aircraft seg mentation simply-curved wrapped sheet reach ing bulkhead former next either forward aft take Henschel HS 126 fuselage shown immediately apparent cockpit zone side sheets could easily installed buckling However leaves problem manage apparent compound curvatures ward aft remember series connecting short straight lines can look like curve particularly short-line pieces small angles can divide shell segments join small angles start fattest pair bulkheads place skin panel extendpast both bulkheads least 3/16 inch Under overhand will cement strip strip will now provide joining surface next skin panels fore aft will turn extend past its next bulkhead process can repeated procedure thus carried both fore aft alternation permitting work panel preceding dries place progressing structure should appear shown drawing now delighted can produce shell what other structural considera tions should like such reinforcements such things landing gear struts engine mounts Concentrated loads must diffused shells landing gear strut must fastened fuselage ring stiffener bulkhead loads spread out local fracture will occur necessary plan ahead install strut mounts blocks whatever bulkhead stringer assembly before skinning As first efforts created complete fuselage before realized mounting members cabane struts would problem relatively easy however add internal sheet lamination beams doublers before shell halves cemented together Local increases skin thickness also often desirable however joint technique de scribed far above does permit direct joining dissimilar thicknesses can done setting joining strip down amount desired thickness increase panel joined make transition 1/32 skin 1/16 necessary install joining strip before trimming already installed skin panel edge trimming thickened edge finally installing actual joining strip course makes first strip spacer Preliminary Planning Choose drawings have reasonably accurate cross sections outlines first trial method avoid aircraft elaborate fillets between wing fuselage tail fuselage drawings produce exact size layout fuselage side view cross sections will need sheet balsa bulkheads skin light fuselage structure rubber power smaller 049 power approximately 24 30 inches long will mean 1/16 bulkheads 1/32 skin shell built two halves con structed side top-view layouts important building surface flat because halfshells will too stiff allow springing forcing together Construction First make upper lower keels 1/16 sheet either cutting contour orby bending fuselage side view has strip 34 Model Aviation Seen both inside outside shell Sections Vega skin 1/16 balsa sheet Before joining author installs control mechanisms similar real aircraft Two halves P-51 Mustang shell ready forjoin ing rigid accurate no monkey business force fitting Navion shells matched cementedheld together rubber bands Interior details yet installed Edges simulated metal skin pieces show clearlywill later invisible outline about 3/16 wide Pin drawing board top wax paper-protected drawing cross sections bulkheads carefully cut 1/16 sheet two halves right left half fuselage begun notching set bulkheads keel strips cementing exactly spaced vertical keel members Take special care bulkheads accurately located perpendicular surface Use temporary bracing necessary Once done use straight wood strip check fair lines run length structure strip touches bulkhead edge Correct errors both bulkhead halves before proceeding Either sand edge away add thin padding strip bring bulkhead Out proper fairing Choose largest bulkhead pair cut paper skin wrap outline piece other over bulkhead shown drawing Fig 1 skin panel cut sheet stock grain running fore aft no require ment panel reach top keel bottom may applied two pieces Refer Fig 1 appearance skin panel precautionary notes skin panel secure dry will obvious must now make neat joint between panels lie fore aft accomplished joining strips cut grain running along short dimension strip strips provide gluing shelf described earlier stress carrying members will found some joining strips may need some surface sanding allow its next sheet panel set well sanding can done emery board affects next gluing surface tilting toward next bulkhead use short thin straightedge piece card shelf next bulkhead should contact between straightedge shelf across shelf permits next skin panel cemented voids cement joint single remaining requirement means providing neat skin joint line will found necessary curve forward rear edge skin panel secure neat seam Several strips thin card stock cut very gently curving edges choosing strip appropriate curvature wrapping along edge skin panel place proper edge curvature can found same card strip used Out line cut edge next panel added edge installed panel also prepared way before lengths joining strip cemented its overhanging edge skin thickness changes both installed skin its underlying first shelf must crisply cut Actual working techniques simple can developed experience first fuselage suggested plan make three halves rejecting either first worst Balsa skin stock should C cut will bend easily splitting Ambroid cement Duco other solvent softenable glues used possible use solvent remove poor appearing panels disrupting good ones Hot Stuff Tite Bond other nonsoftenable cements used own better sure before gluing several cautions have nonflat building board will forced sand joining surfaces both halves expect squeeze half shells mate wont deform large pressures fracture 2 should plan bulkheads interior structure accept large loads come wing landing gear etc share skin over reasonably large areas too typical full scale practice 3 can make progressive changes skin thickness front rear strength requirements dictate 4 rigid half shells allow interior installations bulkhead lightening before joining 5 Cock pits wheel wells other large openings must have edge support framing doublers 6 Excess skin thickness can removed sanding desired Lets review what has discussed add some other ideas will helpful Determine exact location extra thick ness skin panels make suitable notations side view Stiffeners reinforcing members should also planned time 2 cross sections keel members should trimmed away allow thickness skin cross sections should also made right left hand halves exactly alike some will receive such loads should close enough other straight lines between pair will approximate Continued page 106 May 1980 35 iwo exampies us rignier-sype sneiis assemuied internal control mechanisms installed Seversky Republic P-35 left German Henschel HS-1 26 right Vuiree u i-i srieem iusewge briell wiui .arveu visible Ned mounts surfaces Ia full scale abhors crude lviii ISUIIIIUI iIlei.naUi suns uarely type horns rods devises reverse too After steps will line again no adverse effects except its back wards stock point system can assembled Make pushrods paying special attention Y pushrod connects two pitch belicranks together Shape shown Figure 2 check smooth operation ranges collective pitch Put extra ball back swash plate can snap antirotation link original arrangement can used although presently using pin slot combination similar found Alouette few closing notesthe screws holding plastic angle bearings tend hit aluminum bracket other side servo plate pushed through Take Moto-Tool grind away aluminum nuts can installed easily need four angle bearings high style Two provided kit Orderpart #3503 other two front pushrod runs straight through lower front aluminum bracket Roughly pencil area rod runs cut portion out sufficient clearance rod pass through swash plate bend IN STOCK FOR IMMEDIATE SHIPMENT QUADRAS QUADRA REPAIR- $1000 plus parts Jim Messers ERCOUPE KIT- $1950O Concepts BIG FLEET KIT- $17995* Barkleys TIGER MOTH KIT- $24995* *inCludes FREE Du-Bro Wheels -SCALE PLANS FOR QUADRA ERCOUPE SKYBOLT- $2000 ea SUPER STEARMAN- $2495 ZINGER & TOP FLITE PROPS- 10% off BALSA & SPRUCE sizes- 45% off COCKPIT KIT Ercoupe- $1500 Stearman $1800 Fleet- $1800 RADIAL ENGINESfor Fleet- $3000 COVER ITE 15 rolls - 20% off 24-Hour Service $200 postage Send Bank Check Money Order JIM MESSERS QUALITY MODEL PRODUCTS 106 Valley View DrAllegany NY 14706 rods bellcranks swash plate Everything works perfectly smooth straight rods straight strong latter step illustrated article hover hinge plate should parallel wooden servo plate Also bellcranks reinforced style should used top bellcranks lead servo arms should shortened 4 mm see Figure 3 foregoing material will enable alleviate problems might have swash plate control systems Kavan Jet Ranger welcome comments questions might have address Ray Hostetler Box 136 Kidron OH 44636 Phone 2 16-8578393 first RC Helicopter Olympics will held Vista CA June 681980 Olympic theme will held throughout contest gold silver bronze medals awarded manufacturers will donate products awards also expected include kits radios etc Compe tition will grouped three classes Nov ice Intermediate Expert Novice fliers can look forward such tasks balloon busting pylon racing limbo others never having leave hovering mode Intermediate Expert filers will put out fires rescue people burning buildings participate drag races looping lim bos will also separate free-style events class separate awards given winners continuous clinic will available modeler has questions about set-up flying RC helicopter 1980 RC Helicopter Olympics de signed around Schluter Helicopter Party concept pilots can have fun instead entering grueling contest-like competition past Entertainment planned Saturday June 6 form banquet dinner guest speaker telling about history RC helicopter Films other enjoyable activities also planned Sponsors event North County Blade Busters Contest Director Bob Robeson 173 Sunset Drive No 2 Vista CA 92083 Telephone enquiries handled Charlie Onstott 714 744-9605 Thats month Dont forget pre flight checks Fly safely Dave Chesney Rt 9 Box 621A Greensboro NC 27409 Shell Game/Kragness continued page 35 curve fuselage other words greater curvature closer bulkheads 3 side view drawing must sharply drawn drawing must translucent paper accurately duplicated right left hand sure make fuselage right left half shell 4 Use bulkheads feel desirable much regard weight considerable amount weight can deleted bulkheads cut away narrow half rings just prior final joining two halfshells non-major bulkheads cut-away may extend skin joining strips 5 will find considerable accuracy desirable exact location bulkheads keel strips squareness drawing work board holding keel strips solidly work board surface 6 best gluing clamp final joining strip rubber wound spirally around two halves lightest tension will bring good contact good idea make completely closed shells make cut outs cockpits etc later 7 Some practice experimenting will allow improve technique curious e HS-l 26 shell shown weighs 17 ounces 18 inches long primarily 1/32 skin over 1/16 bulkheads 14 X 1/16 side stringer strip Planked Shells shapes yield best planking Most what said about concen trated loads also applies planked shells As example will discuss Lockheed Vega Orion Sirius Altair etc photos show 1/12-scale model constructed 1/16 planking fuselage geometry totally symmetrical divided cut along horizontal center plane both top bottom identical cut vertical plane right left half shells identical Lockheed Vega fuselage wood molding using two identical shells laminated glue pressed concrete mold 106 Model Aviation REALISMSCALE ACCESSORIES Y WILLIAMS BROTHERS RADIO CONTROL SCALE PILOTS E WHEELS CONTROL-LINECYLINDERS ENGINE KITS MACHINE GUN KITS FREE-FLIGHT STIC DISPLAY MODELS SEND 5Ot FOR COMPLETE ILLUSTRATED CATALOG DEPT MA 181 PAWNEE STREET SAN MARCOS CA 0 92069 JLLA iI2LINc F@RECATOR MOLD YOUR OWN PARTS FOR PLANES BOATS CARS ETC w -w $4995 Instructions assembly & use included $39 Includes A8St Pack ABS ID PREPAID dealer order directUS ONLY Vacuum former plastics Easyto make own Cowls wheel pants Canopies etc works home oven hose type vacuum Cleaner Qualified Dealer Inquiries Invited PLA8TICBuIk Packs ABS PI.tjo Sheet Fornicede sheets 8th 17 Packs Only PCSPACK THICKNESSPER PACKPRICE 0201/50 500 030 1/32 00 045 3/64 00 0601/16 00 090 3/32 00 AssortmentPack see below1500 Asofln, PerkeerIe/os 0-020/4-030/3- 040 2 060/ Sod 1050 shelr doe perk $1500 soOn, ordered ,itl th* FOr,icror AlAS ned/tn Over 3 lbs per pock Idea Development Inc Box 7399 rk Delaware 19711 AEROBATIC AIRPLANES BY ROST C MORRISON .I IS SUPERB DRAWINGS 8395 PLUS ..L SOW POSTA~ CATALOGS ~k-TECN III $100Ocean rule Ken riwy VIOA CR6005 60466 shell skin varying thickness being thicker front landing gear wing engine imposed large loads assembled shells reinforced internal rings longitudinals joined together produce alight strong efficient fuselage good fuselage shell could molded same way would require far too much work making mold reinforcing shells Planking reasonable choice will bit differently however relying less thick balsa technique will start repeating some shell techniques steps already described first step produce side view accurate cross sections stress location such wing spar firewall landing gear attach ment stations Other intermediate cross sections will needed produce good form perhaps reinforce hand-launching grip zone Set up top bottom outline strips drawing erect half bulkheads just done sheet shell assembly Again accurate bulkhead edges will meet join shells mated together Since both halves should identical will use fairing strips find contour changes corrections needed half bulkheads first half shell will correct other halves match Now lay single 16 stringer front rear along hori zontal outer belt line should notch flush bulkheads problem planking fuselage boat hull planks must narrower get smaller sections boat builder has technique calls spilingused establish taper necessary Spiling would very difficult tedious model work tackle problem another way need make long gently-curved taper planks allow change fuselage circum ference will cut curves straightedge Four 1/16 highjigging blocks will cemented cutting board 5/16 X 1/16 strip forced curve blocks straight line cut will become curve strip allowed unbend straight cut made blade several degrees off vertical will bevel edge curved edge can assist getting good edge joint Fig 1 shows layout ofjigging blocks used 1/12 scale Lockheed Vega largest semi-circumference fuselage example 5 expect use -wide planks will 20 planks required However small end has semi-circumference 1 planks must taper 1/16 wide end arithmetic useful accuracy size up producing perfect matching will still have make adjustment last two planks Proceed center line belt line stringer making sure no cement squeezeout interfere next plank Add plank side belt line alternating above below watching progress covering shell fore aft will probably necessary change block spacing cutting jig adjust plank taper final plank does perfectly fill remaining gap top bottom stringer dont worry three-quarters skin place shell can lifted off board tailored plank can placed Lucky 14/Zawada continued page 39 well large propellerseven 11 12 inches diameter use old type Palmer 4-ounce tank pressure silencerthe orifice about 1/16 tank inch deep fuel pick center mounted about 1/16 above spray bar engine Thanks engine runs little faster inverted flight helps little some maneuvers Flying first few flights should made calm light wind regulate height fuel-tank placement spray bar engine speed model straight flight maneuvers different props model must fly slowly lap times around 56 seconds 67-ft lines lap times inverted flight around 54 seconds engine runs must maximum model flies upward two cycle must change runs quickly four cycles model flies downward regulate leadout lines best point during square maneuvers Future Plans course 1980 World Championships Poland next model Lucky 15 1979 season hope will luckier still being made similar dimensions Lucky 14 new airfoil sections own design greater maximum thickness because model will powered 5T46 include airfoil sections plan tail plane will made like tail plane Stiletto 660 Les McDonald stab covered 1/16 balsa Ifyou should have questions ideas about Lucky 14 feel free write care editor CL Aerobatics/Paul continued page 40 founding father Aero Modelers Association Northern California later became WAMWestern Associated Modelers wrote up new set rules Stunt basically same rules being used Northern California occurred fall 1948 early 1949 Accordingto correspondence Roy Mayes little foggy dates much correspondence records 40s destroyed fire Regardless whether new pattern first used 1948 49 Roy introduced some new ideas 1 eight-minute time limit 2 three attempts make two official flights 3 old controversial item appearance points 4 flight pattern points WAM appearance points quite heavy could amount something like 25% total score Roy explained appearance points letters After seeing old time free flight gas models changed semi-realistic models thingies same thing happening Round-the-Pole race cars determined keep same thing happening control line 1949 rules included following sequence starting takeoff level flight climb dive wingover five consecutive inside lpsfive con secutive outside 1oops inverted flight three horizontal figure eights vertical figure eight overhead figure eight square 1oop special ma neuver must described detail judges prior flight landing Appearance points 8 80 1951 special maneuver dropped pattern Otherwise pattern same 51 52 5 l-52 pattern used time old time stunt According rule book 1953 pattern 108 Model Aviation *A COLORFUL * t ** * R AIRPLANE KIT * * Contents4 oIotuI Sheets4-Desians *Folding ineiroctions sWoights Send $200 Pius 50$ Postage Check MO pa Kit laBs 23 wks deliesni HEF Enterprise 7118 Sse,nit Rd. DaIenIII50559
Edition: Model Aviation - 1980/05
Page Numbers: 32, 33, 34, 35, 106, 108
i IL ill U Planked Lockheed Vega one-inch scale shows half shell carrying tail wheel fin supports projects Ned uses owndesigned pylon control arms monofila ment cables running buried surface actu ation mechanisms discernible insert photo FULL-scale stressed skin aircraft have built plywood sheet metal recently fiberglass Sheet shell structures very efficient used reason well obtaining smooth aerodynamic surfaces Shells always lightest structures since thinnest usable material may produce structure much stronger needed account framed structures may best small aircraft Shells function hollow beams depend shape strength stiffness Failure results because local crumpling rupture bend soda straw other paper tube will fail collapsing places wings fuselages ribs rings stiffeners prevent Drawing upon intimate knowledge both full-scale modeling structures author gives us some exciting new ways beat old gameand must plank much improved method tooE Ned Kragness 32 Model Aviation gb stress member/ landing gear center section struts- .--.-- I-- ----~- --- LI--K -- N r . / fattest section Start zone Tern orar brace Top Fig 1Overlapping adjacent skins compound curves coupled judicious sanding approaches real aircraft engineering Wider cross-section skins overlap both ends others end Above Fig 2Precutting planks youll have study text has numerous advantages chief dont end up bunch wildly tapered conventional planks delay such collapse Doublers used increase thickness local high loads structural efficiency scale appearance shells would desirable model structures have much used however because construction difficulties seem too great Occa sional carved hollowed blocks once seen balsa blocks become expensive large sizes small components can still use technique particularly curvature abrupt such engine cowls tailcones transition pieces two broad geometric classes such shells Both classes usually found somewhere aircraft depending structural needs aerodynamic considerations first class curvature character developable means cut along straight line along simple curve resulting shape can unrolled flat sheet common Luscombe fuselage undevelopable sheet second class nondevelopable compound curvature best exemplified egg ball no cut can made will permit us flatten its skin surface shrinking stretch ing tearing skin material non-uniform manner Most aircraft compound forms ap proximated number non-compound curves As familiar example consider common world globe made up number printed flat gores Full-size aircraft usually exploit trick will return later Shell Fuselage Construction Metal plywood skinned fuselage hull structures difficult model compound curvatures must built least attractive method used very light models involves stringers bulkheads covered tissue silk plastic film stringer remains clearly visible will least some bulkhead edges Another method heavier better appearance involves plank ing over bulkheads sanding rough exterior smooth contour finish sophisti cated approaches molding plastics can yield realistic heavier structures Molding May 1980 33 Navion shell showing false structure hold shell alignment until two halves cemented together Scale one-inch plastics however involves making molds different technique producing shells has worked out depends flexibility balsa bending parallel its grain also depends fact full-scale aircraft appear display compound curvatures actually composed simple curves assembled together compound curves individual sheet can same thing examine drawings photographs can frequently discern full-scale aircraft seg mentation simply-curved wrapped sheet reach ing bulkhead former next either forward aft take Henschel HS 126 fuselage shown immediately apparent cockpit zone side sheets could easily installed buckling However leaves problem manage apparent compound curvatures ward aft remember series connecting short straight lines can look like curve particularly short-line pieces small angles can divide shell segments join small angles start fattest pair bulkheads place skin panel extendpast both bulkheads least 3/16 inch Under overhand will cement strip strip will now provide joining surface next skin panels fore aft will turn extend past its next bulkhead process can repeated procedure thus carried both fore aft alternation permitting work panel preceding dries place progressing structure should appear shown drawing now delighted can produce shell what other structural considera tions should like such reinforcements such things landing gear struts engine mounts Concentrated loads must diffused shells landing gear strut must fastened fuselage ring stiffener bulkhead loads spread out local fracture will occur necessary plan ahead install strut mounts blocks whatever bulkhead stringer assembly before skinning As first efforts created complete fuselage before realized mounting members cabane struts would problem relatively easy however add internal sheet lamination beams doublers before shell halves cemented together Local increases skin thickness also often desirable however joint technique de scribed far above does permit direct joining dissimilar thicknesses can done setting joining strip down amount desired thickness increase panel joined make transition 1/32 skin 1/16 necessary install joining strip before trimming already installed skin panel edge trimming thickened edge finally installing actual joining strip course makes first strip spacer Preliminary Planning Choose drawings have reasonably accurate cross sections outlines first trial method avoid aircraft elaborate fillets between wing fuselage tail fuselage drawings produce exact size layout fuselage side view cross sections will need sheet balsa bulkheads skin light fuselage structure rubber power smaller 049 power approximately 24 30 inches long will mean 1/16 bulkheads 1/32 skin shell built two halves con structed side top-view layouts important building surface flat because halfshells will too stiff allow springing forcing together Construction First make upper lower keels 1/16 sheet either cutting contour orby bending fuselage side view has strip 34 Model Aviation Seen both inside outside shell Sections Vega skin 1/16 balsa sheet Before joining author installs control mechanisms similar real aircraft Two halves P-51 Mustang shell ready forjoin ing rigid accurate no monkey business force fitting Navion shells matched cementedheld together rubber bands Interior details yet installed Edges simulated metal skin pieces show clearlywill later invisible outline about 3/16 wide Pin drawing board top wax paper-protected drawing cross sections bulkheads carefully cut 1/16 sheet two halves right left half fuselage begun notching set bulkheads keel strips cementing exactly spaced vertical keel members Take special care bulkheads accurately located perpendicular surface Use temporary bracing necessary Once done use straight wood strip check fair lines run length structure strip touches bulkhead edge Correct errors both bulkhead halves before proceeding Either sand edge away add thin padding strip bring bulkhead Out proper fairing Choose largest bulkhead pair cut paper skin wrap outline piece other over bulkhead shown drawing Fig 1 skin panel cut sheet stock grain running fore aft no require ment panel reach top keel bottom may applied two pieces Refer Fig 1 appearance skin panel precautionary notes skin panel secure dry will obvious must now make neat joint between panels lie fore aft accomplished joining strips cut grain running along short dimension strip strips provide gluing shelf described earlier stress carrying members will found some joining strips may need some surface sanding allow its next sheet panel set well sanding can done emery board affects next gluing surface tilting toward next bulkhead use short thin straightedge piece card shelf next bulkhead should contact between straightedge shelf across shelf permits next skin panel cemented voids cement joint single remaining requirement means providing neat skin joint line will found necessary curve forward rear edge skin panel secure neat seam Several strips thin card stock cut very gently curving edges choosing strip appropriate curvature wrapping along edge skin panel place proper edge curvature can found same card strip used Out line cut edge next panel added edge installed panel also prepared way before lengths joining strip cemented its overhanging edge skin thickness changes both installed skin its underlying first shelf must crisply cut Actual working techniques simple can developed experience first fuselage suggested plan make three halves rejecting either first worst Balsa skin stock should C cut will bend easily splitting Ambroid cement Duco other solvent softenable glues used possible use solvent remove poor appearing panels disrupting good ones Hot Stuff Tite Bond other nonsoftenable cements used own better sure before gluing several cautions have nonflat building board will forced sand joining surfaces both halves expect squeeze half shells mate wont deform large pressures fracture 2 should plan bulkheads interior structure accept large loads come wing landing gear etc share skin over reasonably large areas too typical full scale practice 3 can make progressive changes skin thickness front rear strength requirements dictate 4 rigid half shells allow interior installations bulkhead lightening before joining 5 Cock pits wheel wells other large openings must have edge support framing doublers 6 Excess skin thickness can removed sanding desired Lets review what has discussed add some other ideas will helpful Determine exact location extra thick ness skin panels make suitable notations side view Stiffeners reinforcing members should also planned time 2 cross sections keel members should trimmed away allow thickness skin cross sections should also made right left hand halves exactly alike some will receive such loads should close enough other straight lines between pair will approximate Continued page 106 May 1980 35 iwo exampies us rignier-sype sneiis assemuied internal control mechanisms installed Seversky Republic P-35 left German Henschel HS-1 26 right Vuiree u i-i srieem iusewge briell wiui .arveu visible Ned mounts surfaces Ia full scale abhors crude lviii ISUIIIIUI iIlei.naUi suns uarely type horns rods devises reverse too After steps will line again no adverse effects except its back wards stock point system can assembled Make pushrods paying special attention Y pushrod connects two pitch belicranks together Shape shown Figure 2 check smooth operation ranges collective pitch Put extra ball back swash plate can snap antirotation link original arrangement can used although presently using pin slot combination similar found Alouette few closing notesthe screws holding plastic angle bearings tend hit aluminum bracket other side servo plate pushed through Take Moto-Tool grind away aluminum nuts can installed easily need four angle bearings high style Two provided kit Orderpart #3503 other two front pushrod runs straight through lower front aluminum bracket Roughly pencil area rod runs cut portion out sufficient clearance rod pass through swash plate bend IN STOCK FOR IMMEDIATE SHIPMENT QUADRAS QUADRA REPAIR- $1000 plus parts Jim Messers ERCOUPE KIT- $1950O Concepts BIG FLEET KIT- $17995* Barkleys TIGER MOTH KIT- $24995* *inCludes FREE Du-Bro Wheels -SCALE PLANS FOR QUADRA ERCOUPE SKYBOLT- $2000 ea SUPER STEARMAN- $2495 ZINGER & TOP FLITE PROPS- 10% off BALSA & SPRUCE sizes- 45% off COCKPIT KIT Ercoupe- $1500 Stearman $1800 Fleet- $1800 RADIAL ENGINESfor Fleet- $3000 COVER ITE 15 rolls - 20% off 24-Hour Service $200 postage Send Bank Check Money Order JIM MESSERS QUALITY MODEL PRODUCTS 106 Valley View DrAllegany NY 14706 rods bellcranks swash plate Everything works perfectly smooth straight rods straight strong latter step illustrated article hover hinge plate should parallel wooden servo plate Also bellcranks reinforced style should used top bellcranks lead servo arms should shortened 4 mm see Figure 3 foregoing material will enable alleviate problems might have swash plate control systems Kavan Jet Ranger welcome comments questions might have address Ray Hostetler Box 136 Kidron OH 44636 Phone 2 16-8578393 first RC Helicopter Olympics will held Vista CA June 681980 Olympic theme will held throughout contest gold silver bronze medals awarded manufacturers will donate products awards also expected include kits radios etc Compe tition will grouped three classes Nov ice Intermediate Expert Novice fliers can look forward such tasks balloon busting pylon racing limbo others never having leave hovering mode Intermediate Expert filers will put out fires rescue people burning buildings participate drag races looping lim bos will also separate free-style events class separate awards given winners continuous clinic will available modeler has questions about set-up flying RC helicopter 1980 RC Helicopter Olympics de signed around Schluter Helicopter Party concept pilots can have fun instead entering grueling contest-like competition past Entertainment planned Saturday June 6 form banquet dinner guest speaker telling about history RC helicopter Films other enjoyable activities also planned Sponsors event North County Blade Busters Contest Director Bob Robeson 173 Sunset Drive No 2 Vista CA 92083 Telephone enquiries handled Charlie Onstott 714 744-9605 Thats month Dont forget pre flight checks Fly safely Dave Chesney Rt 9 Box 621A Greensboro NC 27409 Shell Game/Kragness continued page 35 curve fuselage other words greater curvature closer bulkheads 3 side view drawing must sharply drawn drawing must translucent paper accurately duplicated right left hand sure make fuselage right left half shell 4 Use bulkheads feel desirable much regard weight considerable amount weight can deleted bulkheads cut away narrow half rings just prior final joining two halfshells non-major bulkheads cut-away may extend skin joining strips 5 will find considerable accuracy desirable exact location bulkheads keel strips squareness drawing work board holding keel strips solidly work board surface 6 best gluing clamp final joining strip rubber wound spirally around two halves lightest tension will bring good contact good idea make completely closed shells make cut outs cockpits etc later 7 Some practice experimenting will allow improve technique curious e HS-l 26 shell shown weighs 17 ounces 18 inches long primarily 1/32 skin over 1/16 bulkheads 14 X 1/16 side stringer strip Planked Shells shapes yield best planking Most what said about concen trated loads also applies planked shells As example will discuss Lockheed Vega Orion Sirius Altair etc photos show 1/12-scale model constructed 1/16 planking fuselage geometry totally symmetrical divided cut along horizontal center plane both top bottom identical cut vertical plane right left half shells identical Lockheed Vega fuselage wood molding using two identical shells laminated glue pressed concrete mold 106 Model Aviation REALISMSCALE ACCESSORIES Y WILLIAMS BROTHERS RADIO CONTROL SCALE PILOTS E WHEELS CONTROL-LINECYLINDERS ENGINE KITS MACHINE GUN KITS FREE-FLIGHT STIC DISPLAY MODELS SEND 5Ot FOR COMPLETE ILLUSTRATED CATALOG DEPT MA 181 PAWNEE STREET SAN MARCOS CA 0 92069 JLLA iI2LINc F@RECATOR MOLD YOUR OWN PARTS FOR PLANES BOATS CARS ETC w -w $4995 Instructions assembly & use included $39 Includes A8St Pack ABS ID PREPAID dealer order directUS ONLY Vacuum former plastics Easyto make own Cowls wheel pants Canopies etc works home oven hose type vacuum Cleaner Qualified Dealer Inquiries Invited PLA8TICBuIk Packs ABS PI.tjo Sheet Fornicede sheets 8th 17 Packs Only PCSPACK THICKNESSPER PACKPRICE 0201/50 500 030 1/32 00 045 3/64 00 0601/16 00 090 3/32 00 AssortmentPack see below1500 Asofln, PerkeerIe/os 0-020/4-030/3- 040 2 060/ Sod 1050 shelr doe perk $1500 soOn, ordered ,itl th* FOr,icror AlAS ned/tn Over 3 lbs per pock Idea Development Inc Box 7399 rk Delaware 19711 AEROBATIC AIRPLANES BY ROST C MORRISON .I IS SUPERB DRAWINGS 8395 PLUS ..L SOW POSTA~ CATALOGS ~k-TECN III $100Ocean rule Ken riwy VIOA CR6005 60466 shell skin varying thickness being thicker front landing gear wing engine imposed large loads assembled shells reinforced internal rings longitudinals joined together produce alight strong efficient fuselage good fuselage shell could molded same way would require far too much work making mold reinforcing shells Planking reasonable choice will bit differently however relying less thick balsa technique will start repeating some shell techniques steps already described first step produce side view accurate cross sections stress location such wing spar firewall landing gear attach ment stations Other intermediate cross sections will needed produce good form perhaps reinforce hand-launching grip zone Set up top bottom outline strips drawing erect half bulkheads just done sheet shell assembly Again accurate bulkhead edges will meet join shells mated together Since both halves should identical will use fairing strips find contour changes corrections needed half bulkheads first half shell will correct other halves match Now lay single 16 stringer front rear along hori zontal outer belt line should notch flush bulkheads problem planking fuselage boat hull planks must narrower get smaller sections boat builder has technique calls spilingused establish taper necessary Spiling would very difficult tedious model work tackle problem another way need make long gently-curved taper planks allow change fuselage circum ference will cut curves straightedge Four 1/16 highjigging blocks will cemented cutting board 5/16 X 1/16 strip forced curve blocks straight line cut will become curve strip allowed unbend straight cut made blade several degrees off vertical will bevel edge curved edge can assist getting good edge joint Fig 1 shows layout ofjigging blocks used 1/12 scale Lockheed Vega largest semi-circumference fuselage example 5 expect use -wide planks will 20 planks required However small end has semi-circumference 1 planks must taper 1/16 wide end arithmetic useful accuracy size up producing perfect matching will still have make adjustment last two planks Proceed center line belt line stringer making sure no cement squeezeout interfere next plank Add plank side belt line alternating above below watching progress covering shell fore aft will probably necessary change block spacing cutting jig adjust plank taper final plank does perfectly fill remaining gap top bottom stringer dont worry three-quarters skin place shell can lifted off board tailored plank can placed Lucky 14/Zawada continued page 39 well large propellerseven 11 12 inches diameter use old type Palmer 4-ounce tank pressure silencerthe orifice about 1/16 tank inch deep fuel pick center mounted about 1/16 above spray bar engine Thanks engine runs little faster inverted flight helps little some maneuvers Flying first few flights should made calm light wind regulate height fuel-tank placement spray bar engine speed model straight flight maneuvers different props model must fly slowly lap times around 56 seconds 67-ft lines lap times inverted flight around 54 seconds engine runs must maximum model flies upward two cycle must change runs quickly four cycles model flies downward regulate leadout lines best point during square maneuvers Future Plans course 1980 World Championships Poland next model Lucky 15 1979 season hope will luckier still being made similar dimensions Lucky 14 new airfoil sections own design greater maximum thickness because model will powered 5T46 include airfoil sections plan tail plane will made like tail plane Stiletto 660 Les McDonald stab covered 1/16 balsa Ifyou should have questions ideas about Lucky 14 feel free write care editor CL Aerobatics/Paul continued page 40 founding father Aero Modelers Association Northern California later became WAMWestern Associated Modelers wrote up new set rules Stunt basically same rules being used Northern California occurred fall 1948 early 1949 Accordingto correspondence Roy Mayes little foggy dates much correspondence records 40s destroyed fire Regardless whether new pattern first used 1948 49 Roy introduced some new ideas 1 eight-minute time limit 2 three attempts make two official flights 3 old controversial item appearance points 4 flight pattern points WAM appearance points quite heavy could amount something like 25% total score Roy explained appearance points letters After seeing old time free flight gas models changed semi-realistic models thingies same thing happening Round-the-Pole race cars determined keep same thing happening control line 1949 rules included following sequence starting takeoff level flight climb dive wingover five consecutive inside lpsfive con secutive outside 1oops inverted flight three horizontal figure eights vertical figure eight overhead figure eight square 1oop special ma neuver must described detail judges prior flight landing Appearance points 8 80 1951 special maneuver dropped pattern Otherwise pattern same 51 52 5 l-52 pattern used time old time stunt According rule book 1953 pattern 108 Model Aviation *A COLORFUL * t ** * R AIRPLANE KIT * * Contents4 oIotuI Sheets4-Desians *Folding ineiroctions sWoights Send $200 Pius 50$ Postage Check MO pa Kit laBs 23 wks deliesni HEF Enterprise 7118 Sse,nit Rd. DaIenIII50559
Edition: Model Aviation - 1980/05
Page Numbers: 32, 33, 34, 35, 106, 108
i IL ill U Planked Lockheed Vega one-inch scale shows half shell carrying tail wheel fin supports projects Ned uses owndesigned pylon control arms monofila ment cables running buried surface actu ation mechanisms discernible insert photo FULL-scale stressed skin aircraft have built plywood sheet metal recently fiberglass Sheet shell structures very efficient used reason well obtaining smooth aerodynamic surfaces Shells always lightest structures since thinnest usable material may produce structure much stronger needed account framed structures may best small aircraft Shells function hollow beams depend shape strength stiffness Failure results because local crumpling rupture bend soda straw other paper tube will fail collapsing places wings fuselages ribs rings stiffeners prevent Drawing upon intimate knowledge both full-scale modeling structures author gives us some exciting new ways beat old gameand must plank much improved method tooE Ned Kragness 32 Model Aviation gb stress member/ landing gear center section struts- .--.-- I-- ----~- --- LI--K -- N r . / fattest section Start zone Tern orar brace Top Fig 1Overlapping adjacent skins compound curves coupled judicious sanding approaches real aircraft engineering Wider cross-section skins overlap both ends others end Above Fig 2Precutting planks youll have study text has numerous advantages chief dont end up bunch wildly tapered conventional planks delay such collapse Doublers used increase thickness local high loads structural efficiency scale appearance shells would desirable model structures have much used however because construction difficulties seem too great Occa sional carved hollowed blocks once seen balsa blocks become expensive large sizes small components can still use technique particularly curvature abrupt such engine cowls tailcones transition pieces two broad geometric classes such shells Both classes usually found somewhere aircraft depending structural needs aerodynamic considerations first class curvature character developable means cut along straight line along simple curve resulting shape can unrolled flat sheet common Luscombe fuselage undevelopable sheet second class nondevelopable compound curvature best exemplified egg ball no cut can made will permit us flatten its skin surface shrinking stretch ing tearing skin material non-uniform manner Most aircraft compound forms ap proximated number non-compound curves As familiar example consider common world globe made up number printed flat gores Full-size aircraft usually exploit trick will return later Shell Fuselage Construction Metal plywood skinned fuselage hull structures difficult model compound curvatures must built least attractive method used very light models involves stringers bulkheads covered tissue silk plastic film stringer remains clearly visible will least some bulkhead edges Another method heavier better appearance involves plank ing over bulkheads sanding rough exterior smooth contour finish sophisti cated approaches molding plastics can yield realistic heavier structures Molding May 1980 33 Navion shell showing false structure hold shell alignment until two halves cemented together Scale one-inch plastics however involves making molds different technique producing shells has worked out depends flexibility balsa bending parallel its grain also depends fact full-scale aircraft appear display compound curvatures actually composed simple curves assembled together compound curves individual sheet can same thing examine drawings photographs can frequently discern full-scale aircraft seg mentation simply-curved wrapped sheet reach ing bulkhead former next either forward aft take Henschel HS 126 fuselage shown immediately apparent cockpit zone side sheets could easily installed buckling However leaves problem manage apparent compound curvatures ward aft remember series connecting short straight lines can look like curve particularly short-line pieces small angles can divide shell segments join small angles start fattest pair bulkheads place skin panel extendpast both bulkheads least 3/16 inch Under overhand will cement strip strip will now provide joining surface next skin panels fore aft will turn extend past its next bulkhead process can repeated procedure thus carried both fore aft alternation permitting work panel preceding dries place progressing structure should appear shown drawing now delighted can produce shell what other structural considera tions should like such reinforcements such things landing gear struts engine mounts Concentrated loads must diffused shells landing gear strut must fastened fuselage ring stiffener bulkhead loads spread out local fracture will occur necessary plan ahead install strut mounts blocks whatever bulkhead stringer assembly before skinning As first efforts created complete fuselage before realized mounting members cabane struts would problem relatively easy however add internal sheet lamination beams doublers before shell halves cemented together Local increases skin thickness also often desirable however joint technique de scribed far above does permit direct joining dissimilar thicknesses can done setting joining strip down amount desired thickness increase panel joined make transition 1/32 skin 1/16 necessary install joining strip before trimming already installed skin panel edge trimming thickened edge finally installing actual joining strip course makes first strip spacer Preliminary Planning Choose drawings have reasonably accurate cross sections outlines first trial method avoid aircraft elaborate fillets between wing fuselage tail fuselage drawings produce exact size layout fuselage side view cross sections will need sheet balsa bulkheads skin light fuselage structure rubber power smaller 049 power approximately 24 30 inches long will mean 1/16 bulkheads 1/32 skin shell built two halves con structed side top-view layouts important building surface flat because halfshells will too stiff allow springing forcing together Construction First make upper lower keels 1/16 sheet either cutting contour orby bending fuselage side view has strip 34 Model Aviation Seen both inside outside shell Sections Vega skin 1/16 balsa sheet Before joining author installs control mechanisms similar real aircraft Two halves P-51 Mustang shell ready forjoin ing rigid accurate no monkey business force fitting Navion shells matched cementedheld together rubber bands Interior details yet installed Edges simulated metal skin pieces show clearlywill later invisible outline about 3/16 wide Pin drawing board top wax paper-protected drawing cross sections bulkheads carefully cut 1/16 sheet two halves right left half fuselage begun notching set bulkheads keel strips cementing exactly spaced vertical keel members Take special care bulkheads accurately located perpendicular surface Use temporary bracing necessary Once done use straight wood strip check fair lines run length structure strip touches bulkhead edge Correct errors both bulkhead halves before proceeding Either sand edge away add thin padding strip bring bulkhead Out proper fairing Choose largest bulkhead pair cut paper skin wrap outline piece other over bulkhead shown drawing Fig 1 skin panel cut sheet stock grain running fore aft no require ment panel reach top keel bottom may applied two pieces Refer Fig 1 appearance skin panel precautionary notes skin panel secure dry will obvious must now make neat joint between panels lie fore aft accomplished joining strips cut grain running along short dimension strip strips provide gluing shelf described earlier stress carrying members will found some joining strips may need some surface sanding allow its next sheet panel set well sanding can done emery board affects next gluing surface tilting toward next bulkhead use short thin straightedge piece card shelf next bulkhead should contact between straightedge shelf across shelf permits next skin panel cemented voids cement joint single remaining requirement means providing neat skin joint line will found necessary curve forward rear edge skin panel secure neat seam Several strips thin card stock cut very gently curving edges choosing strip appropriate curvature wrapping along edge skin panel place proper edge curvature can found same card strip used Out line cut edge next panel added edge installed panel also prepared way before lengths joining strip cemented its overhanging edge skin thickness changes both installed skin its underlying first shelf must crisply cut Actual working techniques simple can developed experience first fuselage suggested plan make three halves rejecting either first worst Balsa skin stock should C cut will bend easily splitting Ambroid cement Duco other solvent softenable glues used possible use solvent remove poor appearing panels disrupting good ones Hot Stuff Tite Bond other nonsoftenable cements used own better sure before gluing several cautions have nonflat building board will forced sand joining surfaces both halves expect squeeze half shells mate wont deform large pressures fracture 2 should plan bulkheads interior structure accept large loads come wing landing gear etc share skin over reasonably large areas too typical full scale practice 3 can make progressive changes skin thickness front rear strength requirements dictate 4 rigid half shells allow interior installations bulkhead lightening before joining 5 Cock pits wheel wells other large openings must have edge support framing doublers 6 Excess skin thickness can removed sanding desired Lets review what has discussed add some other ideas will helpful Determine exact location extra thick ness skin panels make suitable notations side view Stiffeners reinforcing members should also planned time 2 cross sections keel members should trimmed away allow thickness skin cross sections should also made right left hand halves exactly alike some will receive such loads should close enough other straight lines between pair will approximate Continued page 106 May 1980 35 iwo exampies us rignier-sype sneiis assemuied internal control mechanisms installed Seversky Republic P-35 left German Henschel HS-1 26 right Vuiree u i-i srieem iusewge briell wiui .arveu visible Ned mounts surfaces Ia full scale abhors crude lviii ISUIIIIUI iIlei.naUi suns uarely type horns rods devises reverse too After steps will line again no adverse effects except its back wards stock point system can assembled Make pushrods paying special attention Y pushrod connects two pitch belicranks together Shape shown Figure 2 check smooth operation ranges collective pitch Put extra ball back swash plate can snap antirotation link original arrangement can used although presently using pin slot combination similar found Alouette few closing notesthe screws holding plastic angle bearings tend hit aluminum bracket other side servo plate pushed through Take Moto-Tool grind away aluminum nuts can installed easily need four angle bearings high style Two provided kit Orderpart #3503 other two front pushrod runs straight through lower front aluminum bracket Roughly pencil area rod runs cut portion out sufficient clearance rod pass through swash plate bend IN STOCK FOR IMMEDIATE SHIPMENT QUADRAS QUADRA REPAIR- $1000 plus parts Jim Messers ERCOUPE KIT- $1950O Concepts BIG FLEET KIT- $17995* Barkleys TIGER MOTH KIT- $24995* *inCludes FREE Du-Bro Wheels -SCALE PLANS FOR QUADRA ERCOUPE SKYBOLT- $2000 ea SUPER STEARMAN- $2495 ZINGER & TOP FLITE PROPS- 10% off BALSA & SPRUCE sizes- 45% off COCKPIT KIT Ercoupe- $1500 Stearman $1800 Fleet- $1800 RADIAL ENGINESfor Fleet- $3000 COVER ITE 15 rolls - 20% off 24-Hour Service $200 postage Send Bank Check Money Order JIM MESSERS QUALITY MODEL PRODUCTS 106 Valley View DrAllegany NY 14706 rods bellcranks swash plate Everything works perfectly smooth straight rods straight strong latter step illustrated article hover hinge plate should parallel wooden servo plate Also bellcranks reinforced style should used top bellcranks lead servo arms should shortened 4 mm see Figure 3 foregoing material will enable alleviate problems might have swash plate control systems Kavan Jet Ranger welcome comments questions might have address Ray Hostetler Box 136 Kidron OH 44636 Phone 2 16-8578393 first RC Helicopter Olympics will held Vista CA June 681980 Olympic theme will held throughout contest gold silver bronze medals awarded manufacturers will donate products awards also expected include kits radios etc Compe tition will grouped three classes Nov ice Intermediate Expert Novice fliers can look forward such tasks balloon busting pylon racing limbo others never having leave hovering mode Intermediate Expert filers will put out fires rescue people burning buildings participate drag races looping lim bos will also separate free-style events class separate awards given winners continuous clinic will available modeler has questions about set-up flying RC helicopter 1980 RC Helicopter Olympics de signed around Schluter Helicopter Party concept pilots can have fun instead entering grueling contest-like competition past Entertainment planned Saturday June 6 form banquet dinner guest speaker telling about history RC helicopter Films other enjoyable activities also planned Sponsors event North County Blade Busters Contest Director Bob Robeson 173 Sunset Drive No 2 Vista CA 92083 Telephone enquiries handled Charlie Onstott 714 744-9605 Thats month Dont forget pre flight checks Fly safely Dave Chesney Rt 9 Box 621A Greensboro NC 27409 Shell Game/Kragness continued page 35 curve fuselage other words greater curvature closer bulkheads 3 side view drawing must sharply drawn drawing must translucent paper accurately duplicated right left hand sure make fuselage right left half shell 4 Use bulkheads feel desirable much regard weight considerable amount weight can deleted bulkheads cut away narrow half rings just prior final joining two halfshells non-major bulkheads cut-away may extend skin joining strips 5 will find considerable accuracy desirable exact location bulkheads keel strips squareness drawing work board holding keel strips solidly work board surface 6 best gluing clamp final joining strip rubber wound spirally around two halves lightest tension will bring good contact good idea make completely closed shells make cut outs cockpits etc later 7 Some practice experimenting will allow improve technique curious e HS-l 26 shell shown weighs 17 ounces 18 inches long primarily 1/32 skin over 1/16 bulkheads 14 X 1/16 side stringer strip Planked Shells shapes yield best planking Most what said about concen trated loads also applies planked shells As example will discuss Lockheed Vega Orion Sirius Altair etc photos show 1/12-scale model constructed 1/16 planking fuselage geometry totally symmetrical divided cut along horizontal center plane both top bottom identical cut vertical plane right left half shells identical Lockheed Vega fuselage wood molding using two identical shells laminated glue pressed concrete mold 106 Model Aviation REALISMSCALE ACCESSORIES Y WILLIAMS BROTHERS RADIO CONTROL SCALE PILOTS E WHEELS CONTROL-LINECYLINDERS ENGINE KITS MACHINE GUN KITS FREE-FLIGHT STIC DISPLAY MODELS SEND 5Ot FOR COMPLETE ILLUSTRATED CATALOG DEPT MA 181 PAWNEE STREET SAN MARCOS CA 0 92069 JLLA iI2LINc F@RECATOR MOLD YOUR OWN PARTS FOR PLANES BOATS CARS ETC w -w $4995 Instructions assembly & use included $39 Includes A8St Pack ABS ID PREPAID dealer order directUS ONLY Vacuum former plastics Easyto make own Cowls wheel pants Canopies etc works home oven hose type vacuum Cleaner Qualified Dealer Inquiries Invited PLA8TICBuIk Packs ABS PI.tjo Sheet Fornicede sheets 8th 17 Packs Only PCSPACK THICKNESSPER PACKPRICE 0201/50 500 030 1/32 00 045 3/64 00 0601/16 00 090 3/32 00 AssortmentPack see below1500 Asofln, PerkeerIe/os 0-020/4-030/3- 040 2 060/ Sod 1050 shelr doe perk $1500 soOn, ordered ,itl th* FOr,icror AlAS ned/tn Over 3 lbs per pock Idea Development Inc Box 7399 rk Delaware 19711 AEROBATIC AIRPLANES BY ROST C MORRISON .I IS SUPERB DRAWINGS 8395 PLUS ..L SOW POSTA~ CATALOGS ~k-TECN III $100Ocean rule Ken riwy VIOA CR6005 60466 shell skin varying thickness being thicker front landing gear wing engine imposed large loads assembled shells reinforced internal rings longitudinals joined together produce alight strong efficient fuselage good fuselage shell could molded same way would require far too much work making mold reinforcing shells Planking reasonable choice will bit differently however relying less thick balsa technique will start repeating some shell techniques steps already described first step produce side view accurate cross sections stress location such wing spar firewall landing gear attach ment stations Other intermediate cross sections will needed produce good form perhaps reinforce hand-launching grip zone Set up top bottom outline strips drawing erect half bulkheads just done sheet shell assembly Again accurate bulkhead edges will meet join shells mated together Since both halves should identical will use fairing strips find contour changes corrections needed half bulkheads first half shell will correct other halves match Now lay single 16 stringer front rear along hori zontal outer belt line should notch flush bulkheads problem planking fuselage boat hull planks must narrower get smaller sections boat builder has technique calls spilingused establish taper necessary Spiling would very difficult tedious model work tackle problem another way need make long gently-curved taper planks allow change fuselage circum ference will cut curves straightedge Four 1/16 highjigging blocks will cemented cutting board 5/16 X 1/16 strip forced curve blocks straight line cut will become curve strip allowed unbend straight cut made blade several degrees off vertical will bevel edge curved edge can assist getting good edge joint Fig 1 shows layout ofjigging blocks used 1/12 scale Lockheed Vega largest semi-circumference fuselage example 5 expect use -wide planks will 20 planks required However small end has semi-circumference 1 planks must taper 1/16 wide end arithmetic useful accuracy size up producing perfect matching will still have make adjustment last two planks Proceed center line belt line stringer making sure no cement squeezeout interfere next plank Add plank side belt line alternating above below watching progress covering shell fore aft will probably necessary change block spacing cutting jig adjust plank taper final plank does perfectly fill remaining gap top bottom stringer dont worry three-quarters skin place shell can lifted off board tailored plank can placed Lucky 14/Zawada continued page 39 well large propellerseven 11 12 inches diameter use old type Palmer 4-ounce tank pressure silencerthe orifice about 1/16 tank inch deep fuel pick center mounted about 1/16 above spray bar engine Thanks engine runs little faster inverted flight helps little some maneuvers Flying first few flights should made calm light wind regulate height fuel-tank placement spray bar engine speed model straight flight maneuvers different props model must fly slowly lap times around 56 seconds 67-ft lines lap times inverted flight around 54 seconds engine runs must maximum model flies upward two cycle must change runs quickly four cycles model flies downward regulate leadout lines best point during square maneuvers Future Plans course 1980 World Championships Poland next model Lucky 15 1979 season hope will luckier still being made similar dimensions Lucky 14 new airfoil sections own design greater maximum thickness because model will powered 5T46 include airfoil sections plan tail plane will made like tail plane Stiletto 660 Les McDonald stab covered 1/16 balsa Ifyou should have questions ideas about Lucky 14 feel free write care editor CL Aerobatics/Paul continued page 40 founding father Aero Modelers Association Northern California later became WAMWestern Associated Modelers wrote up new set rules Stunt basically same rules being used Northern California occurred fall 1948 early 1949 Accordingto correspondence Roy Mayes little foggy dates much correspondence records 40s destroyed fire Regardless whether new pattern first used 1948 49 Roy introduced some new ideas 1 eight-minute time limit 2 three attempts make two official flights 3 old controversial item appearance points 4 flight pattern points WAM appearance points quite heavy could amount something like 25% total score Roy explained appearance points letters After seeing old time free flight gas models changed semi-realistic models thingies same thing happening Round-the-Pole race cars determined keep same thing happening control line 1949 rules included following sequence starting takeoff level flight climb dive wingover five consecutive inside lpsfive con secutive outside 1oops inverted flight three horizontal figure eights vertical figure eight overhead figure eight square 1oop special ma neuver must described detail judges prior flight landing Appearance points 8 80 1951 special maneuver dropped pattern Otherwise pattern same 51 52 5 l-52 pattern used time old time stunt According rule book 1953 pattern 108 Model Aviation *A COLORFUL * t ** * R AIRPLANE KIT * * Contents4 oIotuI Sheets4-Desians *Folding ineiroctions sWoights Send $200 Pius 50$ Postage Check MO pa Kit laBs 23 wks deliesni HEF Enterprise 7118 Sse,nit Rd. DaIenIII50559
Edition: Model Aviation - 1980/05
Page Numbers: 32, 33, 34, 35, 106, 108
i IL ill U Planked Lockheed Vega one-inch scale shows half shell carrying tail wheel fin supports projects Ned uses owndesigned pylon control arms monofila ment cables running buried surface actu ation mechanisms discernible insert photo FULL-scale stressed skin aircraft have built plywood sheet metal recently fiberglass Sheet shell structures very efficient used reason well obtaining smooth aerodynamic surfaces Shells always lightest structures since thinnest usable material may produce structure much stronger needed account framed structures may best small aircraft Shells function hollow beams depend shape strength stiffness Failure results because local crumpling rupture bend soda straw other paper tube will fail collapsing places wings fuselages ribs rings stiffeners prevent Drawing upon intimate knowledge both full-scale modeling structures author gives us some exciting new ways beat old gameand must plank much improved method tooE Ned Kragness 32 Model Aviation gb stress member/ landing gear center section struts- .--.-- I-- ----~- --- LI--K -- N r . / fattest section Start zone Tern orar brace Top Fig 1Overlapping adjacent skins compound curves coupled judicious sanding approaches real aircraft engineering Wider cross-section skins overlap both ends others end Above Fig 2Precutting planks youll have study text has numerous advantages chief dont end up bunch wildly tapered conventional planks delay such collapse Doublers used increase thickness local high loads structural efficiency scale appearance shells would desirable model structures have much used however because construction difficulties seem too great Occa sional carved hollowed blocks once seen balsa blocks become expensive large sizes small components can still use technique particularly curvature abrupt such engine cowls tailcones transition pieces two broad geometric classes such shells Both classes usually found somewhere aircraft depending structural needs aerodynamic considerations first class curvature character developable means cut along straight line along simple curve resulting shape can unrolled flat sheet common Luscombe fuselage undevelopable sheet second class nondevelopable compound curvature best exemplified egg ball no cut can made will permit us flatten its skin surface shrinking stretch ing tearing skin material non-uniform manner Most aircraft compound forms ap proximated number non-compound curves As familiar example consider common world globe made up number printed flat gores Full-size aircraft usually exploit trick will return later Shell Fuselage Construction Metal plywood skinned fuselage hull structures difficult model compound curvatures must built least attractive method used very light models involves stringers bulkheads covered tissue silk plastic film stringer remains clearly visible will least some bulkhead edges Another method heavier better appearance involves plank ing over bulkheads sanding rough exterior smooth contour finish sophisti cated approaches molding plastics can yield realistic heavier structures Molding May 1980 33 Navion shell showing false structure hold shell alignment until two halves cemented together Scale one-inch plastics however involves making molds different technique producing shells has worked out depends flexibility balsa bending parallel its grain also depends fact full-scale aircraft appear display compound curvatures actually composed simple curves assembled together compound curves individual sheet can same thing examine drawings photographs can frequently discern full-scale aircraft seg mentation simply-curved wrapped sheet reach ing bulkhead former next either forward aft take Henschel HS 126 fuselage shown immediately apparent cockpit zone side sheets could easily installed buckling However leaves problem manage apparent compound curvatures ward aft remember series connecting short straight lines can look like curve particularly short-line pieces small angles can divide shell segments join small angles start fattest pair bulkheads place skin panel extendpast both bulkheads least 3/16 inch Under overhand will cement strip strip will now provide joining surface next skin panels fore aft will turn extend past its next bulkhead process can repeated procedure thus carried both fore aft alternation permitting work panel preceding dries place progressing structure should appear shown drawing now delighted can produce shell what other structural considera tions should like such reinforcements such things landing gear struts engine mounts Concentrated loads must diffused shells landing gear strut must fastened fuselage ring stiffener bulkhead loads spread out local fracture will occur necessary plan ahead install strut mounts blocks whatever bulkhead stringer assembly before skinning As first efforts created complete fuselage before realized mounting members cabane struts would problem relatively easy however add internal sheet lamination beams doublers before shell halves cemented together Local increases skin thickness also often desirable however joint technique de scribed far above does permit direct joining dissimilar thicknesses can done setting joining strip down amount desired thickness increase panel joined make transition 1/32 skin 1/16 necessary install joining strip before trimming already installed skin panel edge trimming thickened edge finally installing actual joining strip course makes first strip spacer Preliminary Planning Choose drawings have reasonably accurate cross sections outlines first trial method avoid aircraft elaborate fillets between wing fuselage tail fuselage drawings produce exact size layout fuselage side view cross sections will need sheet balsa bulkheads skin light fuselage structure rubber power smaller 049 power approximately 24 30 inches long will mean 1/16 bulkheads 1/32 skin shell built two halves con structed side top-view layouts important building surface flat because halfshells will too stiff allow springing forcing together Construction First make upper lower keels 1/16 sheet either cutting contour orby bending fuselage side view has strip 34 Model Aviation Seen both inside outside shell Sections Vega skin 1/16 balsa sheet Before joining author installs control mechanisms similar real aircraft Two halves P-51 Mustang shell ready forjoin ing rigid accurate no monkey business force fitting Navion shells matched cementedheld together rubber bands Interior details yet installed Edges simulated metal skin pieces show clearlywill later invisible outline about 3/16 wide Pin drawing board top wax paper-protected drawing cross sections bulkheads carefully cut 1/16 sheet two halves right left half fuselage begun notching set bulkheads keel strips cementing exactly spaced vertical keel members Take special care bulkheads accurately located perpendicular surface Use temporary bracing necessary Once done use straight wood strip check fair lines run length structure strip touches bulkhead edge Correct errors both bulkhead halves before proceeding Either sand edge away add thin padding strip bring bulkhead Out proper fairing Choose largest bulkhead pair cut paper skin wrap outline piece other over bulkhead shown drawing Fig 1 skin panel cut sheet stock grain running fore aft no require ment panel reach top keel bottom may applied two pieces Refer Fig 1 appearance skin panel precautionary notes skin panel secure dry will obvious must now make neat joint between panels lie fore aft accomplished joining strips cut grain running along short dimension strip strips provide gluing shelf described earlier stress carrying members will found some joining strips may need some surface sanding allow its next sheet panel set well sanding can done emery board affects next gluing surface tilting toward next bulkhead use short thin straightedge piece card shelf next bulkhead should contact between straightedge shelf across shelf permits next skin panel cemented voids cement joint single remaining requirement means providing neat skin joint line will found necessary curve forward rear edge skin panel secure neat seam Several strips thin card stock cut very gently curving edges choosing strip appropriate curvature wrapping along edge skin panel place proper edge curvature can found same card strip used Out line cut edge next panel added edge installed panel also prepared way before lengths joining strip cemented its overhanging edge skin thickness changes both installed skin its underlying first shelf must crisply cut Actual working techniques simple can developed experience first fuselage suggested plan make three halves rejecting either first worst Balsa skin stock should C cut will bend easily splitting Ambroid cement Duco other solvent softenable glues used possible use solvent remove poor appearing panels disrupting good ones Hot Stuff Tite Bond other nonsoftenable cements used own better sure before gluing several cautions have nonflat building board will forced sand joining surfaces both halves expect squeeze half shells mate wont deform large pressures fracture 2 should plan bulkheads interior structure accept large loads come wing landing gear etc share skin over reasonably large areas too typical full scale practice 3 can make progressive changes skin thickness front rear strength requirements dictate 4 rigid half shells allow interior installations bulkhead lightening before joining 5 Cock pits wheel wells other large openings must have edge support framing doublers 6 Excess skin thickness can removed sanding desired Lets review what has discussed add some other ideas will helpful Determine exact location extra thick ness skin panels make suitable notations side view Stiffeners reinforcing members should also planned time 2 cross sections keel members should trimmed away allow thickness skin cross sections should also made right left hand halves exactly alike some will receive such loads should close enough other straight lines between pair will approximate Continued page 106 May 1980 35 iwo exampies us rignier-sype sneiis assemuied internal control mechanisms installed Seversky Republic P-35 left German Henschel HS-1 26 right Vuiree u i-i srieem iusewge briell wiui .arveu visible Ned mounts surfaces Ia full scale abhors crude lviii ISUIIIIUI iIlei.naUi suns uarely type horns rods devises reverse too After steps will line again no adverse effects except its back wards stock point system can assembled Make pushrods paying special attention Y pushrod connects two pitch belicranks together Shape shown Figure 2 check smooth operation ranges collective pitch Put extra ball back swash plate can snap antirotation link original arrangement can used although presently using pin slot combination similar found Alouette few closing notesthe screws holding plastic angle bearings tend hit aluminum bracket other side servo plate pushed through Take Moto-Tool grind away aluminum nuts can installed easily need four angle bearings high style Two provided kit Orderpart #3503 other two front pushrod runs straight through lower front aluminum bracket Roughly pencil area rod runs cut portion out sufficient clearance rod pass through swash plate bend IN STOCK FOR IMMEDIATE SHIPMENT QUADRAS QUADRA REPAIR- $1000 plus parts Jim Messers ERCOUPE KIT- $1950O Concepts BIG FLEET KIT- $17995* Barkleys TIGER MOTH KIT- $24995* *inCludes FREE Du-Bro Wheels -SCALE PLANS FOR QUADRA ERCOUPE SKYBOLT- $2000 ea SUPER STEARMAN- $2495 ZINGER & TOP FLITE PROPS- 10% off BALSA & SPRUCE sizes- 45% off COCKPIT KIT Ercoupe- $1500 Stearman $1800 Fleet- $1800 RADIAL ENGINESfor Fleet- $3000 COVER ITE 15 rolls - 20% off 24-Hour Service $200 postage Send Bank Check Money Order JIM MESSERS QUALITY MODEL PRODUCTS 106 Valley View DrAllegany NY 14706 rods bellcranks swash plate Everything works perfectly smooth straight rods straight strong latter step illustrated article hover hinge plate should parallel wooden servo plate Also bellcranks reinforced style should used top bellcranks lead servo arms should shortened 4 mm see Figure 3 foregoing material will enable alleviate problems might have swash plate control systems Kavan Jet Ranger welcome comments questions might have address Ray Hostetler Box 136 Kidron OH 44636 Phone 2 16-8578393 first RC Helicopter Olympics will held Vista CA June 681980 Olympic theme will held throughout contest gold silver bronze medals awarded manufacturers will donate products awards also expected include kits radios etc Compe tition will grouped three classes Nov ice Intermediate Expert Novice fliers can look forward such tasks balloon busting pylon racing limbo others never having leave hovering mode Intermediate Expert filers will put out fires rescue people burning buildings participate drag races looping lim bos will also separate free-style events class separate awards given winners continuous clinic will available modeler has questions about set-up flying RC helicopter 1980 RC Helicopter Olympics de signed around Schluter Helicopter Party concept pilots can have fun instead entering grueling contest-like competition past Entertainment planned Saturday June 6 form banquet dinner guest speaker telling about history RC helicopter Films other enjoyable activities also planned Sponsors event North County Blade Busters Contest Director Bob Robeson 173 Sunset Drive No 2 Vista CA 92083 Telephone enquiries handled Charlie Onstott 714 744-9605 Thats month Dont forget pre flight checks Fly safely Dave Chesney Rt 9 Box 621A Greensboro NC 27409 Shell Game/Kragness continued page 35 curve fuselage other words greater curvature closer bulkheads 3 side view drawing must sharply drawn drawing must translucent paper accurately duplicated right left hand sure make fuselage right left half shell 4 Use bulkheads feel desirable much regard weight considerable amount weight can deleted bulkheads cut away narrow half rings just prior final joining two halfshells non-major bulkheads cut-away may extend skin joining strips 5 will find considerable accuracy desirable exact location bulkheads keel strips squareness drawing work board holding keel strips solidly work board surface 6 best gluing clamp final joining strip rubber wound spirally around two halves lightest tension will bring good contact good idea make completely closed shells make cut outs cockpits etc later 7 Some practice experimenting will allow improve technique curious e HS-l 26 shell shown weighs 17 ounces 18 inches long primarily 1/32 skin over 1/16 bulkheads 14 X 1/16 side stringer strip Planked Shells shapes yield best planking Most what said about concen trated loads also applies planked shells As example will discuss Lockheed Vega Orion Sirius Altair etc photos show 1/12-scale model constructed 1/16 planking fuselage geometry totally symmetrical divided cut along horizontal center plane both top bottom identical cut vertical plane right left half shells identical Lockheed Vega fuselage wood molding using two identical shells laminated glue pressed concrete mold 106 Model Aviation REALISMSCALE ACCESSORIES Y WILLIAMS BROTHERS RADIO CONTROL SCALE PILOTS E WHEELS CONTROL-LINECYLINDERS ENGINE KITS MACHINE GUN KITS FREE-FLIGHT STIC DISPLAY MODELS SEND 5Ot FOR COMPLETE ILLUSTRATED CATALOG DEPT MA 181 PAWNEE STREET SAN MARCOS CA 0 92069 JLLA iI2LINc F@RECATOR MOLD YOUR OWN PARTS FOR PLANES BOATS CARS ETC w -w $4995 Instructions assembly & use included $39 Includes A8St Pack ABS ID PREPAID dealer order directUS ONLY Vacuum former plastics Easyto make own Cowls wheel pants Canopies etc works home oven hose type vacuum Cleaner Qualified Dealer Inquiries Invited PLA8TICBuIk Packs ABS PI.tjo Sheet Fornicede sheets 8th 17 Packs Only PCSPACK THICKNESSPER PACKPRICE 0201/50 500 030 1/32 00 045 3/64 00 0601/16 00 090 3/32 00 AssortmentPack see below1500 Asofln, PerkeerIe/os 0-020/4-030/3- 040 2 060/ Sod 1050 shelr doe perk $1500 soOn, ordered ,itl th* FOr,icror AlAS ned/tn Over 3 lbs per pock Idea Development Inc Box 7399 rk Delaware 19711 AEROBATIC AIRPLANES BY ROST C MORRISON .I IS SUPERB DRAWINGS 8395 PLUS ..L SOW POSTA~ CATALOGS ~k-TECN III $100Ocean rule Ken riwy VIOA CR6005 60466 shell skin varying thickness being thicker front landing gear wing engine imposed large loads assembled shells reinforced internal rings longitudinals joined together produce alight strong efficient fuselage good fuselage shell could molded same way would require far too much work making mold reinforcing shells Planking reasonable choice will bit differently however relying less thick balsa technique will start repeating some shell techniques steps already described first step produce side view accurate cross sections stress location such wing spar firewall landing gear attach ment stations Other intermediate cross sections will needed produce good form perhaps reinforce hand-launching grip zone Set up top bottom outline strips drawing erect half bulkheads just done sheet shell assembly Again accurate bulkhead edges will meet join shells mated together Since both halves should identical will use fairing strips find contour changes corrections needed half bulkheads first half shell will correct other halves match Now lay single 16 stringer front rear along hori zontal outer belt line should notch flush bulkheads problem planking fuselage boat hull planks must narrower get smaller sections boat builder has technique calls spilingused establish taper necessary Spiling would very difficult tedious model work tackle problem another way need make long gently-curved taper planks allow change fuselage circum ference will cut curves straightedge Four 1/16 highjigging blocks will cemented cutting board 5/16 X 1/16 strip forced curve blocks straight line cut will become curve strip allowed unbend straight cut made blade several degrees off vertical will bevel edge curved edge can assist getting good edge joint Fig 1 shows layout ofjigging blocks used 1/12 scale Lockheed Vega largest semi-circumference fuselage example 5 expect use -wide planks will 20 planks required However small end has semi-circumference 1 planks must taper 1/16 wide end arithmetic useful accuracy size up producing perfect matching will still have make adjustment last two planks Proceed center line belt line stringer making sure no cement squeezeout interfere next plank Add plank side belt line alternating above below watching progress covering shell fore aft will probably necessary change block spacing cutting jig adjust plank taper final plank does perfectly fill remaining gap top bottom stringer dont worry three-quarters skin place shell can lifted off board tailored plank can placed Lucky 14/Zawada continued page 39 well large propellerseven 11 12 inches diameter use old type Palmer 4-ounce tank pressure silencerthe orifice about 1/16 tank inch deep fuel pick center mounted about 1/16 above spray bar engine Thanks engine runs little faster inverted flight helps little some maneuvers Flying first few flights should made calm light wind regulate height fuel-tank placement spray bar engine speed model straight flight maneuvers different props model must fly slowly lap times around 56 seconds 67-ft lines lap times inverted flight around 54 seconds engine runs must maximum model flies upward two cycle must change runs quickly four cycles model flies downward regulate leadout lines best point during square maneuvers Future Plans course 1980 World Championships Poland next model Lucky 15 1979 season hope will luckier still being made similar dimensions Lucky 14 new airfoil sections own design greater maximum thickness because model will powered 5T46 include airfoil sections plan tail plane will made like tail plane Stiletto 660 Les McDonald stab covered 1/16 balsa Ifyou should have questions ideas about Lucky 14 feel free write care editor CL Aerobatics/Paul continued page 40 founding father Aero Modelers Association Northern California later became WAMWestern Associated Modelers wrote up new set rules Stunt basically same rules being used Northern California occurred fall 1948 early 1949 Accordingto correspondence Roy Mayes little foggy dates much correspondence records 40s destroyed fire Regardless whether new pattern first used 1948 49 Roy introduced some new ideas 1 eight-minute time limit 2 three attempts make two official flights 3 old controversial item appearance points 4 flight pattern points WAM appearance points quite heavy could amount something like 25% total score Roy explained appearance points letters After seeing old time free flight gas models changed semi-realistic models thingies same thing happening Round-the-Pole race cars determined keep same thing happening control line 1949 rules included following sequence starting takeoff level flight climb dive wingover five consecutive inside lpsfive con secutive outside 1oops inverted flight three horizontal figure eights vertical figure eight overhead figure eight square 1oop special ma neuver must described detail judges prior flight landing Appearance points 8 80 1951 special maneuver dropped pattern Otherwise pattern same 51 52 5 l-52 pattern used time old time stunt According rule book 1953 pattern 108 Model Aviation *A COLORFUL * t ** * R AIRPLANE KIT * * Contents4 oIotuI Sheets4-Desians *Folding ineiroctions sWoights Send $200 Pius 50$ Postage Check MO pa Kit laBs 23 wks deliesni HEF Enterprise 7118 Sse,nit Rd. DaIenIII50559
Edition: Model Aviation - 1980/05
Page Numbers: 32, 33, 34, 35, 106, 108
i IL ill U Planked Lockheed Vega one-inch scale shows half shell carrying tail wheel fin supports projects Ned uses owndesigned pylon control arms monofila ment cables running buried surface actu ation mechanisms discernible insert photo FULL-scale stressed skin aircraft have built plywood sheet metal recently fiberglass Sheet shell structures very efficient used reason well obtaining smooth aerodynamic surfaces Shells always lightest structures since thinnest usable material may produce structure much stronger needed account framed structures may best small aircraft Shells function hollow beams depend shape strength stiffness Failure results because local crumpling rupture bend soda straw other paper tube will fail collapsing places wings fuselages ribs rings stiffeners prevent Drawing upon intimate knowledge both full-scale modeling structures author gives us some exciting new ways beat old gameand must plank much improved method tooE Ned Kragness 32 Model Aviation gb stress member/ landing gear center section struts- .--.-- I-- ----~- --- LI--K -- N r . / fattest section Start zone Tern orar brace Top Fig 1Overlapping adjacent skins compound curves coupled judicious sanding approaches real aircraft engineering Wider cross-section skins overlap both ends others end Above Fig 2Precutting planks youll have study text has numerous advantages chief dont end up bunch wildly tapered conventional planks delay such collapse Doublers used increase thickness local high loads structural efficiency scale appearance shells would desirable model structures have much used however because construction difficulties seem too great Occa sional carved hollowed blocks once seen balsa blocks become expensive large sizes small components can still use technique particularly curvature abrupt such engine cowls tailcones transition pieces two broad geometric classes such shells Both classes usually found somewhere aircraft depending structural needs aerodynamic considerations first class curvature character developable means cut along straight line along simple curve resulting shape can unrolled flat sheet common Luscombe fuselage undevelopable sheet second class nondevelopable compound curvature best exemplified egg ball no cut can made will permit us flatten its skin surface shrinking stretch ing tearing skin material non-uniform manner Most aircraft compound forms ap proximated number non-compound curves As familiar example consider common world globe made up number printed flat gores Full-size aircraft usually exploit trick will return later Shell Fuselage Construction Metal plywood skinned fuselage hull structures difficult model compound curvatures must built least attractive method used very light models involves stringers bulkheads covered tissue silk plastic film stringer remains clearly visible will least some bulkhead edges Another method heavier better appearance involves plank ing over bulkheads sanding rough exterior smooth contour finish sophisti cated approaches molding plastics can yield realistic heavier structures Molding May 1980 33 Navion shell showing false structure hold shell alignment until two halves cemented together Scale one-inch plastics however involves making molds different technique producing shells has worked out depends flexibility balsa bending parallel its grain also depends fact full-scale aircraft appear display compound curvatures actually composed simple curves assembled together compound curves individual sheet can same thing examine drawings photographs can frequently discern full-scale aircraft seg mentation simply-curved wrapped sheet reach ing bulkhead former next either forward aft take Henschel HS 126 fuselage shown immediately apparent cockpit zone side sheets could easily installed buckling However leaves problem manage apparent compound curvatures ward aft remember series connecting short straight lines can look like curve particularly short-line pieces small angles can divide shell segments join small angles start fattest pair bulkheads place skin panel extendpast both bulkheads least 3/16 inch Under overhand will cement strip strip will now provide joining surface next skin panels fore aft will turn extend past its next bulkhead process can repeated procedure thus carried both fore aft alternation permitting work panel preceding dries place progressing structure should appear shown drawing now delighted can produce shell what other structural considera tions should like such reinforcements such things landing gear struts engine mounts Concentrated loads must diffused shells landing gear strut must fastened fuselage ring stiffener bulkhead loads spread out local fracture will occur necessary plan ahead install strut mounts blocks whatever bulkhead stringer assembly before skinning As first efforts created complete fuselage before realized mounting members cabane struts would problem relatively easy however add internal sheet lamination beams doublers before shell halves cemented together Local increases skin thickness also often desirable however joint technique de scribed far above does permit direct joining dissimilar thicknesses can done setting joining strip down amount desired thickness increase panel joined make transition 1/32 skin 1/16 necessary install joining strip before trimming already installed skin panel edge trimming thickened edge finally installing actual joining strip course makes first strip spacer Preliminary Planning Choose drawings have reasonably accurate cross sections outlines first trial method avoid aircraft elaborate fillets between wing fuselage tail fuselage drawings produce exact size layout fuselage side view cross sections will need sheet balsa bulkheads skin light fuselage structure rubber power smaller 049 power approximately 24 30 inches long will mean 1/16 bulkheads 1/32 skin shell built two halves con structed side top-view layouts important building surface flat because halfshells will too stiff allow springing forcing together Construction First make upper lower keels 1/16 sheet either cutting contour orby bending fuselage side view has strip 34 Model Aviation Seen both inside outside shell Sections Vega skin 1/16 balsa sheet Before joining author installs control mechanisms similar real aircraft Two halves P-51 Mustang shell ready forjoin ing rigid accurate no monkey business force fitting Navion shells matched cementedheld together rubber bands Interior details yet installed Edges simulated metal skin pieces show clearlywill later invisible outline about 3/16 wide Pin drawing board top wax paper-protected drawing cross sections bulkheads carefully cut 1/16 sheet two halves right left half fuselage begun notching set bulkheads keel strips cementing exactly spaced vertical keel members Take special care bulkheads accurately located perpendicular surface Use temporary bracing necessary Once done use straight wood strip check fair lines run length structure strip touches bulkhead edge Correct errors both bulkhead halves before proceeding Either sand edge away add thin padding strip bring bulkhead Out proper fairing Choose largest bulkhead pair cut paper skin wrap outline piece other over bulkhead shown drawing Fig 1 skin panel cut sheet stock grain running fore aft no require ment panel reach top keel bottom may applied two pieces Refer Fig 1 appearance skin panel precautionary notes skin panel secure dry will obvious must now make neat joint between panels lie fore aft accomplished joining strips cut grain running along short dimension strip strips provide gluing shelf described earlier stress carrying members will found some joining strips may need some surface sanding allow its next sheet panel set well sanding can done emery board affects next gluing surface tilting toward next bulkhead use short thin straightedge piece card shelf next bulkhead should contact between straightedge shelf across shelf permits next skin panel cemented voids cement joint single remaining requirement means providing neat skin joint line will found necessary curve forward rear edge skin panel secure neat seam Several strips thin card stock cut very gently curving edges choosing strip appropriate curvature wrapping along edge skin panel place proper edge curvature can found same card strip used Out line cut edge next panel added edge installed panel also prepared way before lengths joining strip cemented its overhanging edge skin thickness changes both installed skin its underlying first shelf must crisply cut Actual working techniques simple can developed experience first fuselage suggested plan make three halves rejecting either first worst Balsa skin stock should C cut will bend easily splitting Ambroid cement Duco other solvent softenable glues used possible use solvent remove poor appearing panels disrupting good ones Hot Stuff Tite Bond other nonsoftenable cements used own better sure before gluing several cautions have nonflat building board will forced sand joining surfaces both halves expect squeeze half shells mate wont deform large pressures fracture 2 should plan bulkheads interior structure accept large loads come wing landing gear etc share skin over reasonably large areas too typical full scale practice 3 can make progressive changes skin thickness front rear strength requirements dictate 4 rigid half shells allow interior installations bulkhead lightening before joining 5 Cock pits wheel wells other large openings must have edge support framing doublers 6 Excess skin thickness can removed sanding desired Lets review what has discussed add some other ideas will helpful Determine exact location extra thick ness skin panels make suitable notations side view Stiffeners reinforcing members should also planned time 2 cross sections keel members should trimmed away allow thickness skin cross sections should also made right left hand halves exactly alike some will receive such loads should close enough other straight lines between pair will approximate Continued page 106 May 1980 35 iwo exampies us rignier-sype sneiis assemuied internal control mechanisms installed Seversky Republic P-35 left German Henschel HS-1 26 right Vuiree u i-i srieem iusewge briell wiui .arveu visible Ned mounts surfaces Ia full scale abhors crude lviii ISUIIIIUI iIlei.naUi suns uarely type horns rods devises reverse too After steps will line again no adverse effects except its back wards stock point system can assembled Make pushrods paying special attention Y pushrod connects two pitch belicranks together Shape shown Figure 2 check smooth operation ranges collective pitch Put extra ball back swash plate can snap antirotation link original arrangement can used although presently using pin slot combination similar found Alouette few closing notesthe screws holding plastic angle bearings tend hit aluminum bracket other side servo plate pushed through Take Moto-Tool grind away aluminum nuts can installed easily need four angle bearings high style Two provided kit Orderpart #3503 other two front pushrod runs straight through lower front aluminum bracket Roughly pencil area rod runs cut portion out sufficient clearance rod pass through swash plate bend IN STOCK FOR IMMEDIATE SHIPMENT QUADRAS QUADRA REPAIR- $1000 plus parts Jim Messers ERCOUPE KIT- $1950O Concepts BIG FLEET KIT- $17995* Barkleys TIGER MOTH KIT- $24995* *inCludes FREE Du-Bro Wheels -SCALE PLANS FOR QUADRA ERCOUPE SKYBOLT- $2000 ea SUPER STEARMAN- $2495 ZINGER & TOP FLITE PROPS- 10% off BALSA & SPRUCE sizes- 45% off COCKPIT KIT Ercoupe- $1500 Stearman $1800 Fleet- $1800 RADIAL ENGINESfor Fleet- $3000 COVER ITE 15 rolls - 20% off 24-Hour Service $200 postage Send Bank Check Money Order JIM MESSERS QUALITY MODEL PRODUCTS 106 Valley View DrAllegany NY 14706 rods bellcranks swash plate Everything works perfectly smooth straight rods straight strong latter step illustrated article hover hinge plate should parallel wooden servo plate Also bellcranks reinforced style should used top bellcranks lead servo arms should shortened 4 mm see Figure 3 foregoing material will enable alleviate problems might have swash plate control systems Kavan Jet Ranger welcome comments questions might have address Ray Hostetler Box 136 Kidron OH 44636 Phone 2 16-8578393 first RC Helicopter Olympics will held Vista CA June 681980 Olympic theme will held throughout contest gold silver bronze medals awarded manufacturers will donate products awards also expected include kits radios etc Compe tition will grouped three classes Nov ice Intermediate Expert Novice fliers can look forward such tasks balloon busting pylon racing limbo others never having leave hovering mode Intermediate Expert filers will put out fires rescue people burning buildings participate drag races looping lim bos will also separate free-style events class separate awards given winners continuous clinic will available modeler has questions about set-up flying RC helicopter 1980 RC Helicopter Olympics de signed around Schluter Helicopter Party concept pilots can have fun instead entering grueling contest-like competition past Entertainment planned Saturday June 6 form banquet dinner guest speaker telling about history RC helicopter Films other enjoyable activities also planned Sponsors event North County Blade Busters Contest Director Bob Robeson 173 Sunset Drive No 2 Vista CA 92083 Telephone enquiries handled Charlie Onstott 714 744-9605 Thats month Dont forget pre flight checks Fly safely Dave Chesney Rt 9 Box 621A Greensboro NC 27409 Shell Game/Kragness continued page 35 curve fuselage other words greater curvature closer bulkheads 3 side view drawing must sharply drawn drawing must translucent paper accurately duplicated right left hand sure make fuselage right left half shell 4 Use bulkheads feel desirable much regard weight considerable amount weight can deleted bulkheads cut away narrow half rings just prior final joining two halfshells non-major bulkheads cut-away may extend skin joining strips 5 will find considerable accuracy desirable exact location bulkheads keel strips squareness drawing work board holding keel strips solidly work board surface 6 best gluing clamp final joining strip rubber wound spirally around two halves lightest tension will bring good contact good idea make completely closed shells make cut outs cockpits etc later 7 Some practice experimenting will allow improve technique curious e HS-l 26 shell shown weighs 17 ounces 18 inches long primarily 1/32 skin over 1/16 bulkheads 14 X 1/16 side stringer strip Planked Shells shapes yield best planking Most what said about concen trated loads also applies planked shells As example will discuss Lockheed Vega Orion Sirius Altair etc photos show 1/12-scale model constructed 1/16 planking fuselage geometry totally symmetrical divided cut along horizontal center plane both top bottom identical cut vertical plane right left half shells identical Lockheed Vega fuselage wood molding using two identical shells laminated glue pressed concrete mold 106 Model Aviation REALISMSCALE ACCESSORIES Y WILLIAMS BROTHERS RADIO CONTROL SCALE PILOTS E WHEELS CONTROL-LINECYLINDERS ENGINE KITS MACHINE GUN KITS FREE-FLIGHT STIC DISPLAY MODELS SEND 5Ot FOR COMPLETE ILLUSTRATED CATALOG DEPT MA 181 PAWNEE STREET SAN MARCOS CA 0 92069 JLLA iI2LINc F@RECATOR MOLD YOUR OWN PARTS FOR PLANES BOATS CARS ETC w -w $4995 Instructions assembly & use included $39 Includes A8St Pack ABS ID PREPAID dealer order directUS ONLY Vacuum former plastics Easyto make own Cowls wheel pants Canopies etc works home oven hose type vacuum Cleaner Qualified Dealer Inquiries Invited PLA8TICBuIk Packs ABS PI.tjo Sheet Fornicede sheets 8th 17 Packs Only PCSPACK THICKNESSPER PACKPRICE 0201/50 500 030 1/32 00 045 3/64 00 0601/16 00 090 3/32 00 AssortmentPack see below1500 Asofln, PerkeerIe/os 0-020/4-030/3- 040 2 060/ Sod 1050 shelr doe perk $1500 soOn, ordered ,itl th* FOr,icror AlAS ned/tn Over 3 lbs per pock Idea Development Inc Box 7399 rk Delaware 19711 AEROBATIC AIRPLANES BY ROST C MORRISON .I IS SUPERB DRAWINGS 8395 PLUS ..L SOW POSTA~ CATALOGS ~k-TECN III $100Ocean rule Ken riwy VIOA CR6005 60466 shell skin varying thickness being thicker front landing gear wing engine imposed large loads assembled shells reinforced internal rings longitudinals joined together produce alight strong efficient fuselage good fuselage shell could molded same way would require far too much work making mold reinforcing shells Planking reasonable choice will bit differently however relying less thick balsa technique will start repeating some shell techniques steps already described first step produce side view accurate cross sections stress location such wing spar firewall landing gear attach ment stations Other intermediate cross sections will needed produce good form perhaps reinforce hand-launching grip zone Set up top bottom outline strips drawing erect half bulkheads just done sheet shell assembly Again accurate bulkhead edges will meet join shells mated together Since both halves should identical will use fairing strips find contour changes corrections needed half bulkheads first half shell will correct other halves match Now lay single 16 stringer front rear along hori zontal outer belt line should notch flush bulkheads problem planking fuselage boat hull planks must narrower get smaller sections boat builder has technique calls spilingused establish taper necessary Spiling would very difficult tedious model work tackle problem another way need make long gently-curved taper planks allow change fuselage circum ference will cut curves straightedge Four 1/16 highjigging blocks will cemented cutting board 5/16 X 1/16 strip forced curve blocks straight line cut will become curve strip allowed unbend straight cut made blade several degrees off vertical will bevel edge curved edge can assist getting good edge joint Fig 1 shows layout ofjigging blocks used 1/12 scale Lockheed Vega largest semi-circumference fuselage example 5 expect use -wide planks will 20 planks required However small end has semi-circumference 1 planks must taper 1/16 wide end arithmetic useful accuracy size up producing perfect matching will still have make adjustment last two planks Proceed center line belt line stringer making sure no cement squeezeout interfere next plank Add plank side belt line alternating above below watching progress covering shell fore aft will probably necessary change block spacing cutting jig adjust plank taper final plank does perfectly fill remaining gap top bottom stringer dont worry three-quarters skin place shell can lifted off board tailored plank can placed Lucky 14/Zawada continued page 39 well large propellerseven 11 12 inches diameter use old type Palmer 4-ounce tank pressure silencerthe orifice about 1/16 tank inch deep fuel pick center mounted about 1/16 above spray bar engine Thanks engine runs little faster inverted flight helps little some maneuvers Flying first few flights should made calm light wind regulate height fuel-tank placement spray bar engine speed model straight flight maneuvers different props model must fly slowly lap times around 56 seconds 67-ft lines lap times inverted flight around 54 seconds engine runs must maximum model flies upward two cycle must change runs quickly four cycles model flies downward regulate leadout lines best point during square maneuvers Future Plans course 1980 World Championships Poland next model Lucky 15 1979 season hope will luckier still being made similar dimensions Lucky 14 new airfoil sections own design greater maximum thickness because model will powered 5T46 include airfoil sections plan tail plane will made like tail plane Stiletto 660 Les McDonald stab covered 1/16 balsa Ifyou should have questions ideas about Lucky 14 feel free write care editor CL Aerobatics/Paul continued page 40 founding father Aero Modelers Association Northern California later became WAMWestern Associated Modelers wrote up new set rules Stunt basically same rules being used Northern California occurred fall 1948 early 1949 Accordingto correspondence Roy Mayes little foggy dates much correspondence records 40s destroyed fire Regardless whether new pattern first used 1948 49 Roy introduced some new ideas 1 eight-minute time limit 2 three attempts make two official flights 3 old controversial item appearance points 4 flight pattern points WAM appearance points quite heavy could amount something like 25% total score Roy explained appearance points letters After seeing old time free flight gas models changed semi-realistic models thingies same thing happening Round-the-Pole race cars determined keep same thing happening control line 1949 rules included following sequence starting takeoff level flight climb dive wingover five consecutive inside lpsfive con secutive outside 1oops inverted flight three horizontal figure eights vertical figure eight overhead figure eight square 1oop special ma neuver must described detail judges prior flight landing Appearance points 8 80 1951 special maneuver dropped pattern Otherwise pattern same 51 52 5 l-52 pattern used time old time stunt According rule book 1953 pattern 108 Model Aviation *A COLORFUL * t ** * R AIRPLANE KIT * * Contents4 oIotuI Sheets4-Desians *Folding ineiroctions sWoights Send $200 Pius 50$ Postage Check MO pa Kit laBs 23 wks deliesni HEF Enterprise 7118 Sse,nit Rd. 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