NEW NATS EVENT recent phone call Texas Scale modeler asked about competition event monster multiengined airplane weighed AMAs 40-lb limit Giant Scale Event 514 heard about newly proposed FAI event large Scale models have good news him February 1988 issue MA presented official schedule Virginia Nats now added event FAI Large Scale weight limit 55 lb addition engine total displacement top limit immense 61 cu could pair Quadra SOs three 35s maximum wing area 538 sq ft larger twin-engine man-carrying aero batic Cri-Cri France Imagine model 18ft span 3-ft chord powered pair Quadra 50s weighing 55 lb flying legally Nats Models class will static judged same manner other FA entrants except judging distance increased 165 ft nearest part model No bonuses will awarded flight score complexity model Maneuvers can enlarged beyond limits set smaller FAI models limits FAI has often accused living past Its strange Nats should adopting FAI event bring US competition up date larger heavier powerful airplanes Landing gears pet peeves single-strut landing gear Scale aircraft wobbles wiggles directions whenever model moves contact runway worst example occurs rough landing gear approaches complete collapse gear mounted softly avoid damage effect Scale appearance near-disaster produce landing gear strut looks acts scalelike manner need copy full-size construction actually goes along initial concept Scale modeling Dont invent just copy extra effort worth investment have now employed telescoping-tube principle six models gears have survived landings have easy models because shock absorbing qualities Smooth taxiing over rough surfaces has added benefit outer tube gear legs has 4130 chrome-molybdenum alloy steel material used fuselage framework en gine mounts landing gears full-size aircraft noted toughness yet surpris ingly easy manipulate using proper tools An ordinary hacksaw blade may disposed lose its teeth after few strokes high-speed alloy steel blade 32 teeth per will cut through quite readily can filed bent slit brazed have obtaining 4130 tube local dealer supplies materials builders cus tom aircraft Another source supply scrap bin local airport As purchased 4130 tube has black oxide coating can re moved fine grade aluminum oxide cloth leaving polished surface accept solder brazing Standard outside diameters increments 062 25 through 50 in incre ments 125 beyond 50 Wall thickness varies 028 062 035 probably best suited purpose tubes intended give good tele scoping fit ordinarily insert brass bushings soldered place provide running fit between outer inner strut members sure good solder joint clean inner surface tube bright smoothness drill few small holes through tube spot bushing soldered Insert bushing Typical single-strut landing gear Bobs 12-year-old Piel Beryl has survived hundreds landings wheel Robart stuffed rubber foam Bottom view shows shockabsorbing construction aluminum scissors used control rotation sliding leg brake hose wire feeds models electric wheel brake 44 Model Aviation Radio Control Scale Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53019 Shock absorbing landing gear feature Francis McCrackens scratch-built Ryan PT-22 quarter-scale spans 90 weighs 178 lb uses Supertigre 2500 power Impact Engineering functional shock struts Jerday Inc have aluminum bodies stainless steel sliding posts/music wire axles Two styles wing nose gear coating solder paste flow molten solder through hole until begins appear other holes Use heavy soldering iron butane torch necessary certain se cure joint Brass tubing same dimensions wall thickness will weigh same steel lacks strength Aluminum tube equal weight would have three times wall thickness Aluminum difficult braze hardware store variety isnt satisfactory landing gears because high-tensile alloy anodized tough finish should removed before brazing Some modelers skilled art brazing aluminum have success us ing alloys such 2024 6061 contain some copper increased strength ease machining find ultimate example Scale modelers art shock struts seen Beechcraft King Air model Ramon Torres winner recent Scale Masters Tournament member team represent US next world championships Italy Ramons struts working parts machined nylon material has number ad vantages Its tough lightweight somewhat resilient also machines well other plastics would also serve such Delrin As full-size landing gears inner sliding member must restrained rotating some means prefer scissors linkage di rect copy prototype aircraft usually aluminum alloy forgings sim ulate type file machine parts 2024 aluminum alloy bar stock reasonable realism file marks can obliterated sandpaper sandblasting using tool Continued page 134 1 Drill hole No 18 drill size bulkhead firewall up 3/8 thick 2 Insert shaft Bulkhead Fitting through hole 3 Screw nut onto backside fitting Bulkhead Fittings Fourmost Bulkhead Fittin sare simple method feed fuel veni lines through solid bulkheads 4 Slip fuel vent tubes job done Bulkhead Fittings provide sealed tank compartment eliminate fuel line chafing Color coded easy identification Weight 1/2 gram Price 2 $295 No 121 FOURMOST PRODUCTS Size 3/32 4040 24th Avenue Forest Grove OR 97116 503 357-2732 Hundreds cowls kits plans Strong lightweight one-piece construction Exact duplicates manufacturers original Also radial cowls wheelpants Send Si 00 8-pg brochure Orcall 703-890-6017 9am-9 pm EDT phone orders information FIBERGLASS MDPtMARtBOXS3O Goodview VA 24095L~J April 1988 45 Bob discusses reason mounting lugs aluminum cylinder flange Gemini 120 twin broke after over 100 hours use thinks due metal fatigue caused combustion detonation machined nylon landing gear legs Ramon Torres prize-winning Beechcraft King Air have functioning shock absorbers SEE YOUR DEALER FIRST U can help you can order direct us sending full price plus $200 handling U fee 116W 19th St POBox 6 Higginsville MO 64037 call 816 584-7121U U U U U U U U U EU... EEEEEEUEE -7mount pressure tap goes answers own questions what would have told him trial error using tach largest expansion area pipe Actually theres pretty good chart MACS published pipes can use get very close right dimensionseven someone elses pipes advice tuning pipe Dont get greedy far better have pipe slightly too long too short Another lesson learned hard way mentions having rebend landing gear after flight because operates off rough field gears bend quite easily common problem Im surprised solu tion hasnt spread through hobby word-of-mouth Maybe metallurgist can ex plain appears after landing gear strut coils wound wire will bend fairly easily either direction solution problem works well ss put gear struts very hot 500 O 5500 F oven half hour quench cold water cant explain metallurgist should write please gear strut becomes much rigid Moving right along Toms questions mechanical retracts work well pneu matic retracts mechanical systems use two retract servos tn-gear setup prefer mechanical retracts because dont want fuss pressure tank control valve pressure tubing dont mind bother stalling pushrods Theres no question pneu matic retracts easier install problems maintenance over life airplane mechanical retracts years used retract servo wing operating three mechanical retracts worked fairly well time last airplane put retract servo wing main gears fuselage nose gear will never again use retract servo Two retract servos much easier stall reliable operate can afford extra two ounces airplane weight costs Tom asked another question bound interesting people landing gears bend easily Does battery drain become problem wheel working Obviously wants know battery can drain down wheel gets hung up wheel well wont go way up back down answer Yes Gears bind up will cause servo operate its stall current can easily severai hundred milliamperes current Since typically fly 500- 800milliampere-hour mAh battery packs doesnt take long drain down strongest battery perfectly pwpurrunu ur modeling Curtlss Robin 049 Engines -Channel RIC 41 Wingspan Electric Power Optional $2206 Oh 003 Very few lull Scale aicaff ideally suited model flight appealing old curtiss Robin horn spruce lines age beautifully proportioned rubber elect nC glow engines Easy end fun build trainerlibe performance Flyline Models catalog 500phone 17031 2730003 FLYLINE MODELS INC V PO Box 2136 FaIrfax Virginia 22e31 USA pack Tom mentioned reason used Rhom pneumatic retracts avoid airborne battery problems Its valid point Toms last question dilly What servos top gun fliers use aileron elevator might think would consen sus manufacturer isnt know Futaba PCM fliers use JR 401 501 ser vos Similarly JR fliers like Fu taba 130 131 servos real consensus should get top-of-the-line servo aileron elevator Franidy lot nuances servo performance top guns can de tect lost rest us RC Scale/Wischers Continued page 45 cleaning spark plugs looking uni form texture scalelike impression Light airplanes sometimes use steel stampings scissors members model can formed aluminum steel hard alloys aluminum dont form well likely crack along sharp bend Aluminum fresh mill can formed reasonably sharp radius year later will orange peel crack along bend Thin steel may better choice wheel axles made 156-indiameter music wire bent inserted lower telescoping part shock strut Lowtemperature solder used secure wire strut Strength solder ample because large area wetted molten solder last assembly step after high-heat brazed joints have made avoid changing tem per music wire would greatly weak en retractable gears retract mechanism always provides suitable structure mounting models wing fuselage Fixed landing gears inserted holes drilled hardwood blocks birch maple preferred spread load over large area possible through spr rounding balsa plywood Steel rods 156-in music wire can passed through hardwood blocks extended rearwardfor example additional hardwood cemented rear spar wing trying spread landing loads large area type construction has used stand hundreds landings Scale models landings perfectly executed shock absorbing struts dissipate impact load model may bounce back air will survive bounce again amount bounce determined springs side struts can hand-wound pur 134 Model Aviation A-J INTERCEPTOR RTF $695 $495 NOn rL$00* *00 $0 00 roe pO$flC$ OooofluuOrIftShoofte$oOOEhS AmUIJU AIRCRAFT COMPANY PO Box 68132 Portland OR 97268 I-U U U U U U U U U U U U U U U U U U U U IMS COMES * LIVE INDOOR MODEL DEMONSTRATIONS * BOAT POND * CAR TRACK * SWAP SHOP * GIANT RAFFLE popular demand International Modeler Show well known producing best model hobby show West coming ATLANTA April/May 1988 present same great model See latest products visit major manufacturers distributors Model Aircraft l Boats l Cars l Engines Radio Control Systems l Railroads ling Accessories STATIC DISPLAY COMPETITION IN MANY CATEGORIES INTERNATIONAL dflW MODELER 1o SHOW April 30 May 11988 Trade-Only Day Friday April 29 hobby show Southeast hun dred major model manufacturers over US have already registered exhibit premier annual extravaganza GEORGIA WORLD CONGRESS CENTER 285 International Blvd NW Atlanta GA ADMISSION Adults $500 Juniors 12 under $300 Children under six free accompanied adult PO Box 10127 Costa Mesa California 92627-0031 SATURDAY APRIL 30 1988 10 am 6 pm SUNDAY MAY 1 1988 10am 5am Phone 714 548-4700 chased local hardware store Spring making described April 1987 column MA Ready-made shock-absorbing landing gear struts time- labor-saver modeler prefers make own willing substitute cash effort Chicago Expo saw Impact Engineering struts made Jer day Inc struts made several sizes main nose gears models varying weight three 15 lb adaptable fixed retract gears Body diameters 375 50 axle sizes 156 312-in diameters struts scalelike appearance fea ture universal installation either fixed re tract gears means pair 6-32 setscrews Axles music wire pressed place ex ternal housing 6061-T6 aluminum alloy lower sliding member made stainless steel aligned upper housing means pin stainless scissors parts carry rotational loads address further information WS Jerday Inc 2100 Stonehill Ct Arlington TX 76012 Four-stroke engine problems Scale modelers will make effort hide disguise models power plant either inside close-fitting cowl hidden far rearward extension shaft Two-stroke engines forgiving enough outlive kind treatment exhaust two-stroke carries away excess heat means unburned fuel earliest lessons after beginning use four-stroke engines discovery high exhaust temperature its effect exhaust pipes mufflers first attempt homemade internally mounted muffler brazed aluminum construction re suited meltdown brazed joints Droplets melted aluminum fell inside cowl solidified rattled around give hint something adrift internally Another hint four-stroke exhaust very hot came discoloration plated ex haust tube convoluted copper pipe purloined household under-sink plumbing As further evidence charred wood ex haust pipe came within about / Direct contact wood kind balsa hardwood through heat sink must avoided because risk fire risk especially great tinder area being fanned unlimited supply oxygen prop blast past columns have recommended cowled engines provided close-fitting baf fles surrounding cylinder cooling fins made certain cooling air directed would good reasoned air would follow path least resistance through cowl outlet baffle necessary force air over engine practice full-size air-cooled engines have come conclusion baffle can close-fitting around cylinder fins models another source cool air carburetor intake particularly amount exhaust pipe also enclosed within cowl Full-size planes air-cooled engines have external duct carry cold air carburetor internal-combustion engines detonation phenomenon occurs within combustion chamber Despite high speed burning fuel cylinder normally still smooth processnot explosion Detonation re sults some factor interferes process smooth burning causes quick violent re action insteadin effect explosion has brought attention source detonation four-stroke engines gestion heated air induction system especially 2000 F above avoid incurring phenomenon detonation full-size air craft having supercharger intercooler mounted downstream supercharger before air enters carburetor used re duce air temperature before reaches cylinders Scale model having exhaust pipe en closed within engine cowl should sufficient air circulation carry away heat hot pipe duct should provided bring cooler air carburetor Most fourstroke single-cylinder engines have carburetors mounted behind engine non-Scale models exhaust externally mounted no problem heat-caused detonation Preignition subsequent detonation likely occur engine under load dur ing climb example know happens because clatter audible ground Enya 120 has resulted damage prop drive washer Enya has flats prop shaft engage close-fitting drive wash er matching flats hole After years operation flats inside aluminum drive washer have disappeared hole now almost round prop nut should tight ened often after flight two Detonation source abuse Detonation enemy four-stroke engine may survive hours some type failure can expected detonation overheated engine persists should learn recognize sound ground detected safest procedure close throt tle land problem will probably solved resetting needle valve slightly April 1988 135 NEW BULK Hardware Packs NEW Low-price glow-driver Power Panel NEW Catamaran Race Boat NEW RC Electric Hovercraft NEW Mini Sailwinch servo NEW Hitih performance nicads NEW High performance Speed Controls NEW Pushrods Name Street Address C ty CATALOG$750 Deducted 1st order over $2500 *U SA JAPAN V *oJ&Jfl . *GERMA1Y 1000s choose Solar rubber powered gliders copters scale lasercut diecut youcut rockets origami some wing span 6 feet ALL MADE OUT OF PAPER Limited number printed 18188423455PAPER AIRPLANES INTERNATIONAL1213822-9185 1521 Morningside Drive Burbank California91508USA richer setting will some power loss engine will run cooler Using tachometer will tell engine peaked should kept mind will run slightly leaner air Detonation backfiring can cause fatigue long run after years abuse Scale model example could lead broken crank shaft happened acquaintance Gemini 120 twin broken aluminum cylinder jacket after 100 hours operation cant certain detonation some time during engines life prime suspect problem loss power last flight model landed engine running errati cally cylinder perceived loose fracture occurred along sharply ma chined corner mounting flange cylinder jacket bolted crankcase full-size air-cooled engines corner always has large radius no radius Gemini cylinder jacket four lugs Geminis mounting flange remained intact prevent ed complete loss head cylinder valves surrounding cornfields new cylinder made lathe 2024-T35 1 aluminum alloy has machined radius mounting flange After inserting old cylinder liner adding piston cylinder heads engine has returned service running good new cylinder polished aluminum oth er black anodized Internally engine showed no wear no carbon gum buildup after 100 hours cas tor oil lubricant future will certainly aware detonation its devastating effect Four-stroke engines too expensive abused RC Soaring/Blakeslee Continued page 47 Blanchard wasnt fazed warmed up engines charged batteries flew DH 10 British bomber give us fix height haze Woody took second Ex pert Two-Meter What heck second Walt Good bad day flying after didnt get see Walt again main traction up RC World flying replica famous Guff pioneer RC plane lost track events later Sunday especially trophy awards kneedeep swamp water trying fish Tom Beck man s Sailaire out tallest oak tree Ive ever seen Later use small-bore shot gun shoot Out tree have reliable sources Ed Berton took first Open Expert Expert overall winner Shaun Ernst won Sportsman Open Rust Smith overall winner category Disaster Disney time between winch retriever break downs share impressions will make conversation far far future Nobody told us until Thirteenth Annual Tangerine New 12-volt winch Russell Keith Flight Line Systems sent photo description new winch offering sale Lets have Keith tell us about own words winch motor rebuilt GM metric-size unit does have shunted field limit speed setup uses less power amount torque produced allows motor smaller lighter shunted motor equal torque Also speed motor constant Under light load speed high load increases speed drops produce smooth launch variation speed helps keep constant tension line also helps prevent backlashes line goes slack motor speeds up keeping line taut may eliminate backlashes helps quite bit spools fabricated steel hub 1 /2-in diameter 6A long end plates 4-in thick diameter six inches end plates fitted onto shoulder gas-tungsten-arc-welded TIG makes very strong durable spool bushing Outer end spool shaft support current price $200 complete plus $10 shipping Anyone would like additional information may contact FLS PO Box 1502 Lewiston ME 04241 Need winch drum have longshaft Ford starter motor just need drum build own winch drums available World Cup Winch Products $7995 plus ship ping costs hub 3-in diameter end plates seven inches World Cup Bud Fox Jim Wichert also sells plans drum complete winch $20 plus postage Write 1791 Glenview St Simi Valley CA 93063 phone 805 526-3327 Customs courtesies Diablo Valley Club Northem California puts out very good newsletter Peter Rambo editor Peter recently printed clubs frequency control safety rules plus following list Customs Courtesies us have Sailpian ing some time tend regard things 136 Model Aviation over 150 NEW ITEMS YOU have never seen before ZMA Zip INTERNATIONAL INC a
Edition: Model Aviation - 1988/04
Page Numbers: 44, 45, 134, 135, 136
NEW NATS EVENT recent phone call Texas Scale modeler asked about competition event monster multiengined airplane weighed AMAs 40-lb limit Giant Scale Event 514 heard about newly proposed FAI event large Scale models have good news him February 1988 issue MA presented official schedule Virginia Nats now added event FAI Large Scale weight limit 55 lb addition engine total displacement top limit immense 61 cu could pair Quadra SOs three 35s maximum wing area 538 sq ft larger twin-engine man-carrying aero batic Cri-Cri France Imagine model 18ft span 3-ft chord powered pair Quadra 50s weighing 55 lb flying legally Nats Models class will static judged same manner other FA entrants except judging distance increased 165 ft nearest part model No bonuses will awarded flight score complexity model Maneuvers can enlarged beyond limits set smaller FAI models limits FAI has often accused living past Its strange Nats should adopting FAI event bring US competition up date larger heavier powerful airplanes Landing gears pet peeves single-strut landing gear Scale aircraft wobbles wiggles directions whenever model moves contact runway worst example occurs rough landing gear approaches complete collapse gear mounted softly avoid damage effect Scale appearance near-disaster produce landing gear strut looks acts scalelike manner need copy full-size construction actually goes along initial concept Scale modeling Dont invent just copy extra effort worth investment have now employed telescoping-tube principle six models gears have survived landings have easy models because shock absorbing qualities Smooth taxiing over rough surfaces has added benefit outer tube gear legs has 4130 chrome-molybdenum alloy steel material used fuselage framework en gine mounts landing gears full-size aircraft noted toughness yet surpris ingly easy manipulate using proper tools An ordinary hacksaw blade may disposed lose its teeth after few strokes high-speed alloy steel blade 32 teeth per will cut through quite readily can filed bent slit brazed have obtaining 4130 tube local dealer supplies materials builders cus tom aircraft Another source supply scrap bin local airport As purchased 4130 tube has black oxide coating can re moved fine grade aluminum oxide cloth leaving polished surface accept solder brazing Standard outside diameters increments 062 25 through 50 in incre ments 125 beyond 50 Wall thickness varies 028 062 035 probably best suited purpose tubes intended give good tele scoping fit ordinarily insert brass bushings soldered place provide running fit between outer inner strut members sure good solder joint clean inner surface tube bright smoothness drill few small holes through tube spot bushing soldered Insert bushing Typical single-strut landing gear Bobs 12-year-old Piel Beryl has survived hundreds landings wheel Robart stuffed rubber foam Bottom view shows shockabsorbing construction aluminum scissors used control rotation sliding leg brake hose wire feeds models electric wheel brake 44 Model Aviation Radio Control Scale Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53019 Shock absorbing landing gear feature Francis McCrackens scratch-built Ryan PT-22 quarter-scale spans 90 weighs 178 lb uses Supertigre 2500 power Impact Engineering functional shock struts Jerday Inc have aluminum bodies stainless steel sliding posts/music wire axles Two styles wing nose gear coating solder paste flow molten solder through hole until begins appear other holes Use heavy soldering iron butane torch necessary certain se cure joint Brass tubing same dimensions wall thickness will weigh same steel lacks strength Aluminum tube equal weight would have three times wall thickness Aluminum difficult braze hardware store variety isnt satisfactory landing gears because high-tensile alloy anodized tough finish should removed before brazing Some modelers skilled art brazing aluminum have success us ing alloys such 2024 6061 contain some copper increased strength ease machining find ultimate example Scale modelers art shock struts seen Beechcraft King Air model Ramon Torres winner recent Scale Masters Tournament member team represent US next world championships Italy Ramons struts working parts machined nylon material has number ad vantages Its tough lightweight somewhat resilient also machines well other plastics would also serve such Delrin As full-size landing gears inner sliding member must restrained rotating some means prefer scissors linkage di rect copy prototype aircraft usually aluminum alloy forgings sim ulate type file machine parts 2024 aluminum alloy bar stock reasonable realism file marks can obliterated sandpaper sandblasting using tool Continued page 134 1 Drill hole No 18 drill size bulkhead firewall up 3/8 thick 2 Insert shaft Bulkhead Fitting through hole 3 Screw nut onto backside fitting Bulkhead Fittings Fourmost Bulkhead Fittin sare simple method feed fuel veni lines through solid bulkheads 4 Slip fuel vent tubes job done Bulkhead Fittings provide sealed tank compartment eliminate fuel line chafing Color coded easy identification Weight 1/2 gram Price 2 $295 No 121 FOURMOST PRODUCTS Size 3/32 4040 24th Avenue Forest Grove OR 97116 503 357-2732 Hundreds cowls kits plans Strong lightweight one-piece construction Exact duplicates manufacturers original Also radial cowls wheelpants Send Si 00 8-pg brochure Orcall 703-890-6017 9am-9 pm EDT phone orders information FIBERGLASS MDPtMARtBOXS3O Goodview VA 24095L~J April 1988 45 Bob discusses reason mounting lugs aluminum cylinder flange Gemini 120 twin broke after over 100 hours use thinks due metal fatigue caused combustion detonation machined nylon landing gear legs Ramon Torres prize-winning Beechcraft King Air have functioning shock absorbers SEE YOUR DEALER FIRST U can help you can order direct us sending full price plus $200 handling U fee 116W 19th St POBox 6 Higginsville MO 64037 call 816 584-7121U U U U U U U U U EU... EEEEEEUEE -7mount pressure tap goes answers own questions what would have told him trial error using tach largest expansion area pipe Actually theres pretty good chart MACS published pipes can use get very close right dimensionseven someone elses pipes advice tuning pipe Dont get greedy far better have pipe slightly too long too short Another lesson learned hard way mentions having rebend landing gear after flight because operates off rough field gears bend quite easily common problem Im surprised solu tion hasnt spread through hobby word-of-mouth Maybe metallurgist can ex plain appears after landing gear strut coils wound wire will bend fairly easily either direction solution problem works well ss put gear struts very hot 500 O 5500 F oven half hour quench cold water cant explain metallurgist should write please gear strut becomes much rigid Moving right along Toms questions mechanical retracts work well pneu matic retracts mechanical systems use two retract servos tn-gear setup prefer mechanical retracts because dont want fuss pressure tank control valve pressure tubing dont mind bother stalling pushrods Theres no question pneu matic retracts easier install problems maintenance over life airplane mechanical retracts years used retract servo wing operating three mechanical retracts worked fairly well time last airplane put retract servo wing main gears fuselage nose gear will never again use retract servo Two retract servos much easier stall reliable operate can afford extra two ounces airplane weight costs Tom asked another question bound interesting people landing gears bend easily Does battery drain become problem wheel working Obviously wants know battery can drain down wheel gets hung up wheel well wont go way up back down answer Yes Gears bind up will cause servo operate its stall current can easily severai hundred milliamperes current Since typically fly 500- 800milliampere-hour mAh battery packs doesnt take long drain down strongest battery perfectly pwpurrunu ur modeling Curtlss Robin 049 Engines -Channel RIC 41 Wingspan Electric Power Optional $2206 Oh 003 Very few lull Scale aicaff ideally suited model flight appealing old curtiss Robin horn spruce lines age beautifully proportioned rubber elect nC glow engines Easy end fun build trainerlibe performance Flyline Models catalog 500phone 17031 2730003 FLYLINE MODELS INC V PO Box 2136 FaIrfax Virginia 22e31 USA pack Tom mentioned reason used Rhom pneumatic retracts avoid airborne battery problems Its valid point Toms last question dilly What servos top gun fliers use aileron elevator might think would consen sus manufacturer isnt know Futaba PCM fliers use JR 401 501 ser vos Similarly JR fliers like Fu taba 130 131 servos real consensus should get top-of-the-line servo aileron elevator Franidy lot nuances servo performance top guns can de tect lost rest us RC Scale/Wischers Continued page 45 cleaning spark plugs looking uni form texture scalelike impression Light airplanes sometimes use steel stampings scissors members model can formed aluminum steel hard alloys aluminum dont form well likely crack along sharp bend Aluminum fresh mill can formed reasonably sharp radius year later will orange peel crack along bend Thin steel may better choice wheel axles made 156-indiameter music wire bent inserted lower telescoping part shock strut Lowtemperature solder used secure wire strut Strength solder ample because large area wetted molten solder last assembly step after high-heat brazed joints have made avoid changing tem per music wire would greatly weak en retractable gears retract mechanism always provides suitable structure mounting models wing fuselage Fixed landing gears inserted holes drilled hardwood blocks birch maple preferred spread load over large area possible through spr rounding balsa plywood Steel rods 156-in music wire can passed through hardwood blocks extended rearwardfor example additional hardwood cemented rear spar wing trying spread landing loads large area type construction has used stand hundreds landings Scale models landings perfectly executed shock absorbing struts dissipate impact load model may bounce back air will survive bounce again amount bounce determined springs side struts can hand-wound pur 134 Model Aviation A-J INTERCEPTOR RTF $695 $495 NOn rL$00* *00 $0 00 roe pO$flC$ OooofluuOrIftShoofte$oOOEhS AmUIJU AIRCRAFT COMPANY PO Box 68132 Portland OR 97268 I-U U U U U U U U U U U U U U U U U U U U IMS COMES * LIVE INDOOR MODEL DEMONSTRATIONS * BOAT POND * CAR TRACK * SWAP SHOP * GIANT RAFFLE popular demand International Modeler Show well known producing best model hobby show West coming ATLANTA April/May 1988 present same great model See latest products visit major manufacturers distributors Model Aircraft l Boats l Cars l Engines Radio Control Systems l Railroads ling Accessories STATIC DISPLAY COMPETITION IN MANY CATEGORIES INTERNATIONAL dflW MODELER 1o SHOW April 30 May 11988 Trade-Only Day Friday April 29 hobby show Southeast hun dred major model manufacturers over US have already registered exhibit premier annual extravaganza GEORGIA WORLD CONGRESS CENTER 285 International Blvd NW Atlanta GA ADMISSION Adults $500 Juniors 12 under $300 Children under six free accompanied adult PO Box 10127 Costa Mesa California 92627-0031 SATURDAY APRIL 30 1988 10 am 6 pm SUNDAY MAY 1 1988 10am 5am Phone 714 548-4700 chased local hardware store Spring making described April 1987 column MA Ready-made shock-absorbing landing gear struts time- labor-saver modeler prefers make own willing substitute cash effort Chicago Expo saw Impact Engineering struts made Jer day Inc struts made several sizes main nose gears models varying weight three 15 lb adaptable fixed retract gears Body diameters 375 50 axle sizes 156 312-in diameters struts scalelike appearance fea ture universal installation either fixed re tract gears means pair 6-32 setscrews Axles music wire pressed place ex ternal housing 6061-T6 aluminum alloy lower sliding member made stainless steel aligned upper housing means pin stainless scissors parts carry rotational loads address further information WS Jerday Inc 2100 Stonehill Ct Arlington TX 76012 Four-stroke engine problems Scale modelers will make effort hide disguise models power plant either inside close-fitting cowl hidden far rearward extension shaft Two-stroke engines forgiving enough outlive kind treatment exhaust two-stroke carries away excess heat means unburned fuel earliest lessons after beginning use four-stroke engines discovery high exhaust temperature its effect exhaust pipes mufflers first attempt homemade internally mounted muffler brazed aluminum construction re suited meltdown brazed joints Droplets melted aluminum fell inside cowl solidified rattled around give hint something adrift internally Another hint four-stroke exhaust very hot came discoloration plated ex haust tube convoluted copper pipe purloined household under-sink plumbing As further evidence charred wood ex haust pipe came within about / Direct contact wood kind balsa hardwood through heat sink must avoided because risk fire risk especially great tinder area being fanned unlimited supply oxygen prop blast past columns have recommended cowled engines provided close-fitting baf fles surrounding cylinder cooling fins made certain cooling air directed would good reasoned air would follow path least resistance through cowl outlet baffle necessary force air over engine practice full-size air-cooled engines have come conclusion baffle can close-fitting around cylinder fins models another source cool air carburetor intake particularly amount exhaust pipe also enclosed within cowl Full-size planes air-cooled engines have external duct carry cold air carburetor internal-combustion engines detonation phenomenon occurs within combustion chamber Despite high speed burning fuel cylinder normally still smooth processnot explosion Detonation re sults some factor interferes process smooth burning causes quick violent re action insteadin effect explosion has brought attention source detonation four-stroke engines gestion heated air induction system especially 2000 F above avoid incurring phenomenon detonation full-size air craft having supercharger intercooler mounted downstream supercharger before air enters carburetor used re duce air temperature before reaches cylinders Scale model having exhaust pipe en closed within engine cowl should sufficient air circulation carry away heat hot pipe duct should provided bring cooler air carburetor Most fourstroke single-cylinder engines have carburetors mounted behind engine non-Scale models exhaust externally mounted no problem heat-caused detonation Preignition subsequent detonation likely occur engine under load dur ing climb example know happens because clatter audible ground Enya 120 has resulted damage prop drive washer Enya has flats prop shaft engage close-fitting drive wash er matching flats hole After years operation flats inside aluminum drive washer have disappeared hole now almost round prop nut should tight ened often after flight two Detonation source abuse Detonation enemy four-stroke engine may survive hours some type failure can expected detonation overheated engine persists should learn recognize sound ground detected safest procedure close throt tle land problem will probably solved resetting needle valve slightly April 1988 135 NEW BULK Hardware Packs NEW Low-price glow-driver Power Panel NEW Catamaran Race Boat NEW RC Electric Hovercraft NEW Mini Sailwinch servo NEW Hitih performance nicads NEW High performance Speed Controls NEW Pushrods Name Street Address C ty CATALOG$750 Deducted 1st order over $2500 *U SA JAPAN V *oJ&Jfl . *GERMA1Y 1000s choose Solar rubber powered gliders copters scale lasercut diecut youcut rockets origami some wing span 6 feet ALL MADE OUT OF PAPER Limited number printed 18188423455PAPER AIRPLANES INTERNATIONAL1213822-9185 1521 Morningside Drive Burbank California91508USA richer setting will some power loss engine will run cooler Using tachometer will tell engine peaked should kept mind will run slightly leaner air Detonation backfiring can cause fatigue long run after years abuse Scale model example could lead broken crank shaft happened acquaintance Gemini 120 twin broken aluminum cylinder jacket after 100 hours operation cant certain detonation some time during engines life prime suspect problem loss power last flight model landed engine running errati cally cylinder perceived loose fracture occurred along sharply ma chined corner mounting flange cylinder jacket bolted crankcase full-size air-cooled engines corner always has large radius no radius Gemini cylinder jacket four lugs Geminis mounting flange remained intact prevent ed complete loss head cylinder valves surrounding cornfields new cylinder made lathe 2024-T35 1 aluminum alloy has machined radius mounting flange After inserting old cylinder liner adding piston cylinder heads engine has returned service running good new cylinder polished aluminum oth er black anodized Internally engine showed no wear no carbon gum buildup after 100 hours cas tor oil lubricant future will certainly aware detonation its devastating effect Four-stroke engines too expensive abused RC Soaring/Blakeslee Continued page 47 Blanchard wasnt fazed warmed up engines charged batteries flew DH 10 British bomber give us fix height haze Woody took second Ex pert Two-Meter What heck second Walt Good bad day flying after didnt get see Walt again main traction up RC World flying replica famous Guff pioneer RC plane lost track events later Sunday especially trophy awards kneedeep swamp water trying fish Tom Beck man s Sailaire out tallest oak tree Ive ever seen Later use small-bore shot gun shoot Out tree have reliable sources Ed Berton took first Open Expert Expert overall winner Shaun Ernst won Sportsman Open Rust Smith overall winner category Disaster Disney time between winch retriever break downs share impressions will make conversation far far future Nobody told us until Thirteenth Annual Tangerine New 12-volt winch Russell Keith Flight Line Systems sent photo description new winch offering sale Lets have Keith tell us about own words winch motor rebuilt GM metric-size unit does have shunted field limit speed setup uses less power amount torque produced allows motor smaller lighter shunted motor equal torque Also speed motor constant Under light load speed high load increases speed drops produce smooth launch variation speed helps keep constant tension line also helps prevent backlashes line goes slack motor speeds up keeping line taut may eliminate backlashes helps quite bit spools fabricated steel hub 1 /2-in diameter 6A long end plates 4-in thick diameter six inches end plates fitted onto shoulder gas-tungsten-arc-welded TIG makes very strong durable spool bushing Outer end spool shaft support current price $200 complete plus $10 shipping Anyone would like additional information may contact FLS PO Box 1502 Lewiston ME 04241 Need winch drum have longshaft Ford starter motor just need drum build own winch drums available World Cup Winch Products $7995 plus ship ping costs hub 3-in diameter end plates seven inches World Cup Bud Fox Jim Wichert also sells plans drum complete winch $20 plus postage Write 1791 Glenview St Simi Valley CA 93063 phone 805 526-3327 Customs courtesies Diablo Valley Club Northem California puts out very good newsletter Peter Rambo editor Peter recently printed clubs frequency control safety rules plus following list Customs Courtesies us have Sailpian ing some time tend regard things 136 Model Aviation over 150 NEW ITEMS YOU have never seen before ZMA Zip INTERNATIONAL INC a
Edition: Model Aviation - 1988/04
Page Numbers: 44, 45, 134, 135, 136
NEW NATS EVENT recent phone call Texas Scale modeler asked about competition event monster multiengined airplane weighed AMAs 40-lb limit Giant Scale Event 514 heard about newly proposed FAI event large Scale models have good news him February 1988 issue MA presented official schedule Virginia Nats now added event FAI Large Scale weight limit 55 lb addition engine total displacement top limit immense 61 cu could pair Quadra SOs three 35s maximum wing area 538 sq ft larger twin-engine man-carrying aero batic Cri-Cri France Imagine model 18ft span 3-ft chord powered pair Quadra 50s weighing 55 lb flying legally Nats Models class will static judged same manner other FA entrants except judging distance increased 165 ft nearest part model No bonuses will awarded flight score complexity model Maneuvers can enlarged beyond limits set smaller FAI models limits FAI has often accused living past Its strange Nats should adopting FAI event bring US competition up date larger heavier powerful airplanes Landing gears pet peeves single-strut landing gear Scale aircraft wobbles wiggles directions whenever model moves contact runway worst example occurs rough landing gear approaches complete collapse gear mounted softly avoid damage effect Scale appearance near-disaster produce landing gear strut looks acts scalelike manner need copy full-size construction actually goes along initial concept Scale modeling Dont invent just copy extra effort worth investment have now employed telescoping-tube principle six models gears have survived landings have easy models because shock absorbing qualities Smooth taxiing over rough surfaces has added benefit outer tube gear legs has 4130 chrome-molybdenum alloy steel material used fuselage framework en gine mounts landing gears full-size aircraft noted toughness yet surpris ingly easy manipulate using proper tools An ordinary hacksaw blade may disposed lose its teeth after few strokes high-speed alloy steel blade 32 teeth per will cut through quite readily can filed bent slit brazed have obtaining 4130 tube local dealer supplies materials builders cus tom aircraft Another source supply scrap bin local airport As purchased 4130 tube has black oxide coating can re moved fine grade aluminum oxide cloth leaving polished surface accept solder brazing Standard outside diameters increments 062 25 through 50 in incre ments 125 beyond 50 Wall thickness varies 028 062 035 probably best suited purpose tubes intended give good tele scoping fit ordinarily insert brass bushings soldered place provide running fit between outer inner strut members sure good solder joint clean inner surface tube bright smoothness drill few small holes through tube spot bushing soldered Insert bushing Typical single-strut landing gear Bobs 12-year-old Piel Beryl has survived hundreds landings wheel Robart stuffed rubber foam Bottom view shows shockabsorbing construction aluminum scissors used control rotation sliding leg brake hose wire feeds models electric wheel brake 44 Model Aviation Radio Control Scale Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53019 Shock absorbing landing gear feature Francis McCrackens scratch-built Ryan PT-22 quarter-scale spans 90 weighs 178 lb uses Supertigre 2500 power Impact Engineering functional shock struts Jerday Inc have aluminum bodies stainless steel sliding posts/music wire axles Two styles wing nose gear coating solder paste flow molten solder through hole until begins appear other holes Use heavy soldering iron butane torch necessary certain se cure joint Brass tubing same dimensions wall thickness will weigh same steel lacks strength Aluminum tube equal weight would have three times wall thickness Aluminum difficult braze hardware store variety isnt satisfactory landing gears because high-tensile alloy anodized tough finish should removed before brazing Some modelers skilled art brazing aluminum have success us ing alloys such 2024 6061 contain some copper increased strength ease machining find ultimate example Scale modelers art shock struts seen Beechcraft King Air model Ramon Torres winner recent Scale Masters Tournament member team represent US next world championships Italy Ramons struts working parts machined nylon material has number ad vantages Its tough lightweight somewhat resilient also machines well other plastics would also serve such Delrin As full-size landing gears inner sliding member must restrained rotating some means prefer scissors linkage di rect copy prototype aircraft usually aluminum alloy forgings sim ulate type file machine parts 2024 aluminum alloy bar stock reasonable realism file marks can obliterated sandpaper sandblasting using tool Continued page 134 1 Drill hole No 18 drill size bulkhead firewall up 3/8 thick 2 Insert shaft Bulkhead Fitting through hole 3 Screw nut onto backside fitting Bulkhead Fittings Fourmost Bulkhead Fittin sare simple method feed fuel veni lines through solid bulkheads 4 Slip fuel vent tubes job done Bulkhead Fittings provide sealed tank compartment eliminate fuel line chafing Color coded easy identification Weight 1/2 gram Price 2 $295 No 121 FOURMOST PRODUCTS Size 3/32 4040 24th Avenue Forest Grove OR 97116 503 357-2732 Hundreds cowls kits plans Strong lightweight one-piece construction Exact duplicates manufacturers original Also radial cowls wheelpants Send Si 00 8-pg brochure Orcall 703-890-6017 9am-9 pm EDT phone orders information FIBERGLASS MDPtMARtBOXS3O Goodview VA 24095L~J April 1988 45 Bob discusses reason mounting lugs aluminum cylinder flange Gemini 120 twin broke after over 100 hours use thinks due metal fatigue caused combustion detonation machined nylon landing gear legs Ramon Torres prize-winning Beechcraft King Air have functioning shock absorbers SEE YOUR DEALER FIRST U can help you can order direct us sending full price plus $200 handling U fee 116W 19th St POBox 6 Higginsville MO 64037 call 816 584-7121U U U U U U U U U EU... EEEEEEUEE -7mount pressure tap goes answers own questions what would have told him trial error using tach largest expansion area pipe Actually theres pretty good chart MACS published pipes can use get very close right dimensionseven someone elses pipes advice tuning pipe Dont get greedy far better have pipe slightly too long too short Another lesson learned hard way mentions having rebend landing gear after flight because operates off rough field gears bend quite easily common problem Im surprised solu tion hasnt spread through hobby word-of-mouth Maybe metallurgist can ex plain appears after landing gear strut coils wound wire will bend fairly easily either direction solution problem works well ss put gear struts very hot 500 O 5500 F oven half hour quench cold water cant explain metallurgist should write please gear strut becomes much rigid Moving right along Toms questions mechanical retracts work well pneu matic retracts mechanical systems use two retract servos tn-gear setup prefer mechanical retracts because dont want fuss pressure tank control valve pressure tubing dont mind bother stalling pushrods Theres no question pneu matic retracts easier install problems maintenance over life airplane mechanical retracts years used retract servo wing operating three mechanical retracts worked fairly well time last airplane put retract servo wing main gears fuselage nose gear will never again use retract servo Two retract servos much easier stall reliable operate can afford extra two ounces airplane weight costs Tom asked another question bound interesting people landing gears bend easily Does battery drain become problem wheel working Obviously wants know battery can drain down wheel gets hung up wheel well wont go way up back down answer Yes Gears bind up will cause servo operate its stall current can easily severai hundred milliamperes current Since typically fly 500- 800milliampere-hour mAh battery packs doesnt take long drain down strongest battery perfectly pwpurrunu ur modeling Curtlss Robin 049 Engines -Channel RIC 41 Wingspan Electric Power Optional $2206 Oh 003 Very few lull Scale aicaff ideally suited model flight appealing old curtiss Robin horn spruce lines age beautifully proportioned rubber elect nC glow engines Easy end fun build trainerlibe performance Flyline Models catalog 500phone 17031 2730003 FLYLINE MODELS INC V PO Box 2136 FaIrfax Virginia 22e31 USA pack Tom mentioned reason used Rhom pneumatic retracts avoid airborne battery problems Its valid point Toms last question dilly What servos top gun fliers use aileron elevator might think would consen sus manufacturer isnt know Futaba PCM fliers use JR 401 501 ser vos Similarly JR fliers like Fu taba 130 131 servos real consensus should get top-of-the-line servo aileron elevator Franidy lot nuances servo performance top guns can de tect lost rest us RC Scale/Wischers Continued page 45 cleaning spark plugs looking uni form texture scalelike impression Light airplanes sometimes use steel stampings scissors members model can formed aluminum steel hard alloys aluminum dont form well likely crack along sharp bend Aluminum fresh mill can formed reasonably sharp radius year later will orange peel crack along bend Thin steel may better choice wheel axles made 156-indiameter music wire bent inserted lower telescoping part shock strut Lowtemperature solder used secure wire strut Strength solder ample because large area wetted molten solder last assembly step after high-heat brazed joints have made avoid changing tem per music wire would greatly weak en retractable gears retract mechanism always provides suitable structure mounting models wing fuselage Fixed landing gears inserted holes drilled hardwood blocks birch maple preferred spread load over large area possible through spr rounding balsa plywood Steel rods 156-in music wire can passed through hardwood blocks extended rearwardfor example additional hardwood cemented rear spar wing trying spread landing loads large area type construction has used stand hundreds landings Scale models landings perfectly executed shock absorbing struts dissipate impact load model may bounce back air will survive bounce again amount bounce determined springs side struts can hand-wound pur 134 Model Aviation A-J INTERCEPTOR RTF $695 $495 NOn rL$00* *00 $0 00 roe pO$flC$ OooofluuOrIftShoofte$oOOEhS AmUIJU AIRCRAFT COMPANY PO Box 68132 Portland OR 97268 I-U U U U U U U U U U U U U U U U U U U U IMS COMES * LIVE INDOOR MODEL DEMONSTRATIONS * BOAT POND * CAR TRACK * SWAP SHOP * GIANT RAFFLE popular demand International Modeler Show well known producing best model hobby show West coming ATLANTA April/May 1988 present same great model See latest products visit major manufacturers distributors Model Aircraft l Boats l Cars l Engines Radio Control Systems l Railroads ling Accessories STATIC DISPLAY COMPETITION IN MANY CATEGORIES INTERNATIONAL dflW MODELER 1o SHOW April 30 May 11988 Trade-Only Day Friday April 29 hobby show Southeast hun dred major model manufacturers over US have already registered exhibit premier annual extravaganza GEORGIA WORLD CONGRESS CENTER 285 International Blvd NW Atlanta GA ADMISSION Adults $500 Juniors 12 under $300 Children under six free accompanied adult PO Box 10127 Costa Mesa California 92627-0031 SATURDAY APRIL 30 1988 10 am 6 pm SUNDAY MAY 1 1988 10am 5am Phone 714 548-4700 chased local hardware store Spring making described April 1987 column MA Ready-made shock-absorbing landing gear struts time- labor-saver modeler prefers make own willing substitute cash effort Chicago Expo saw Impact Engineering struts made Jer day Inc struts made several sizes main nose gears models varying weight three 15 lb adaptable fixed retract gears Body diameters 375 50 axle sizes 156 312-in diameters struts scalelike appearance fea ture universal installation either fixed re tract gears means pair 6-32 setscrews Axles music wire pressed place ex ternal housing 6061-T6 aluminum alloy lower sliding member made stainless steel aligned upper housing means pin stainless scissors parts carry rotational loads address further information WS Jerday Inc 2100 Stonehill Ct Arlington TX 76012 Four-stroke engine problems Scale modelers will make effort hide disguise models power plant either inside close-fitting cowl hidden far rearward extension shaft Two-stroke engines forgiving enough outlive kind treatment exhaust two-stroke carries away excess heat means unburned fuel earliest lessons after beginning use four-stroke engines discovery high exhaust temperature its effect exhaust pipes mufflers first attempt homemade internally mounted muffler brazed aluminum construction re suited meltdown brazed joints Droplets melted aluminum fell inside cowl solidified rattled around give hint something adrift internally Another hint four-stroke exhaust very hot came discoloration plated ex haust tube convoluted copper pipe purloined household under-sink plumbing As further evidence charred wood ex haust pipe came within about / Direct contact wood kind balsa hardwood through heat sink must avoided because risk fire risk especially great tinder area being fanned unlimited supply oxygen prop blast past columns have recommended cowled engines provided close-fitting baf fles surrounding cylinder cooling fins made certain cooling air directed would good reasoned air would follow path least resistance through cowl outlet baffle necessary force air over engine practice full-size air-cooled engines have come conclusion baffle can close-fitting around cylinder fins models another source cool air carburetor intake particularly amount exhaust pipe also enclosed within cowl Full-size planes air-cooled engines have external duct carry cold air carburetor internal-combustion engines detonation phenomenon occurs within combustion chamber Despite high speed burning fuel cylinder normally still smooth processnot explosion Detonation re sults some factor interferes process smooth burning causes quick violent re action insteadin effect explosion has brought attention source detonation four-stroke engines gestion heated air induction system especially 2000 F above avoid incurring phenomenon detonation full-size air craft having supercharger intercooler mounted downstream supercharger before air enters carburetor used re duce air temperature before reaches cylinders Scale model having exhaust pipe en closed within engine cowl should sufficient air circulation carry away heat hot pipe duct should provided bring cooler air carburetor Most fourstroke single-cylinder engines have carburetors mounted behind engine non-Scale models exhaust externally mounted no problem heat-caused detonation Preignition subsequent detonation likely occur engine under load dur ing climb example know happens because clatter audible ground Enya 120 has resulted damage prop drive washer Enya has flats prop shaft engage close-fitting drive wash er matching flats hole After years operation flats inside aluminum drive washer have disappeared hole now almost round prop nut should tight ened often after flight two Detonation source abuse Detonation enemy four-stroke engine may survive hours some type failure can expected detonation overheated engine persists should learn recognize sound ground detected safest procedure close throt tle land problem will probably solved resetting needle valve slightly April 1988 135 NEW BULK Hardware Packs NEW Low-price glow-driver Power Panel NEW Catamaran Race Boat NEW RC Electric Hovercraft NEW Mini Sailwinch servo NEW Hitih performance nicads NEW High performance Speed Controls NEW Pushrods Name Street Address C ty CATALOG$750 Deducted 1st order over $2500 *U SA JAPAN V *oJ&Jfl . *GERMA1Y 1000s choose Solar rubber powered gliders copters scale lasercut diecut youcut rockets origami some wing span 6 feet ALL MADE OUT OF PAPER Limited number printed 18188423455PAPER AIRPLANES INTERNATIONAL1213822-9185 1521 Morningside Drive Burbank California91508USA richer setting will some power loss engine will run cooler Using tachometer will tell engine peaked should kept mind will run slightly leaner air Detonation backfiring can cause fatigue long run after years abuse Scale model example could lead broken crank shaft happened acquaintance Gemini 120 twin broken aluminum cylinder jacket after 100 hours operation cant certain detonation some time during engines life prime suspect problem loss power last flight model landed engine running errati cally cylinder perceived loose fracture occurred along sharply ma chined corner mounting flange cylinder jacket bolted crankcase full-size air-cooled engines corner always has large radius no radius Gemini cylinder jacket four lugs Geminis mounting flange remained intact prevent ed complete loss head cylinder valves surrounding cornfields new cylinder made lathe 2024-T35 1 aluminum alloy has machined radius mounting flange After inserting old cylinder liner adding piston cylinder heads engine has returned service running good new cylinder polished aluminum oth er black anodized Internally engine showed no wear no carbon gum buildup after 100 hours cas tor oil lubricant future will certainly aware detonation its devastating effect Four-stroke engines too expensive abused RC Soaring/Blakeslee Continued page 47 Blanchard wasnt fazed warmed up engines charged batteries flew DH 10 British bomber give us fix height haze Woody took second Ex pert Two-Meter What heck second Walt Good bad day flying after didnt get see Walt again main traction up RC World flying replica famous Guff pioneer RC plane lost track events later Sunday especially trophy awards kneedeep swamp water trying fish Tom Beck man s Sailaire out tallest oak tree Ive ever seen Later use small-bore shot gun shoot Out tree have reliable sources Ed Berton took first Open Expert Expert overall winner Shaun Ernst won Sportsman Open Rust Smith overall winner category Disaster Disney time between winch retriever break downs share impressions will make conversation far far future Nobody told us until Thirteenth Annual Tangerine New 12-volt winch Russell Keith Flight Line Systems sent photo description new winch offering sale Lets have Keith tell us about own words winch motor rebuilt GM metric-size unit does have shunted field limit speed setup uses less power amount torque produced allows motor smaller lighter shunted motor equal torque Also speed motor constant Under light load speed high load increases speed drops produce smooth launch variation speed helps keep constant tension line also helps prevent backlashes line goes slack motor speeds up keeping line taut may eliminate backlashes helps quite bit spools fabricated steel hub 1 /2-in diameter 6A long end plates 4-in thick diameter six inches end plates fitted onto shoulder gas-tungsten-arc-welded TIG makes very strong durable spool bushing Outer end spool shaft support current price $200 complete plus $10 shipping Anyone would like additional information may contact FLS PO Box 1502 Lewiston ME 04241 Need winch drum have longshaft Ford starter motor just need drum build own winch drums available World Cup Winch Products $7995 plus ship ping costs hub 3-in diameter end plates seven inches World Cup Bud Fox Jim Wichert also sells plans drum complete winch $20 plus postage Write 1791 Glenview St Simi Valley CA 93063 phone 805 526-3327 Customs courtesies Diablo Valley Club Northem California puts out very good newsletter Peter Rambo editor Peter recently printed clubs frequency control safety rules plus following list Customs Courtesies us have Sailpian ing some time tend regard things 136 Model Aviation over 150 NEW ITEMS YOU have never seen before ZMA Zip INTERNATIONAL INC a
Edition: Model Aviation - 1988/04
Page Numbers: 44, 45, 134, 135, 136
NEW NATS EVENT recent phone call Texas Scale modeler asked about competition event monster multiengined airplane weighed AMAs 40-lb limit Giant Scale Event 514 heard about newly proposed FAI event large Scale models have good news him February 1988 issue MA presented official schedule Virginia Nats now added event FAI Large Scale weight limit 55 lb addition engine total displacement top limit immense 61 cu could pair Quadra SOs three 35s maximum wing area 538 sq ft larger twin-engine man-carrying aero batic Cri-Cri France Imagine model 18ft span 3-ft chord powered pair Quadra 50s weighing 55 lb flying legally Nats Models class will static judged same manner other FA entrants except judging distance increased 165 ft nearest part model No bonuses will awarded flight score complexity model Maneuvers can enlarged beyond limits set smaller FAI models limits FAI has often accused living past Its strange Nats should adopting FAI event bring US competition up date larger heavier powerful airplanes Landing gears pet peeves single-strut landing gear Scale aircraft wobbles wiggles directions whenever model moves contact runway worst example occurs rough landing gear approaches complete collapse gear mounted softly avoid damage effect Scale appearance near-disaster produce landing gear strut looks acts scalelike manner need copy full-size construction actually goes along initial concept Scale modeling Dont invent just copy extra effort worth investment have now employed telescoping-tube principle six models gears have survived landings have easy models because shock absorbing qualities Smooth taxiing over rough surfaces has added benefit outer tube gear legs has 4130 chrome-molybdenum alloy steel material used fuselage framework en gine mounts landing gears full-size aircraft noted toughness yet surpris ingly easy manipulate using proper tools An ordinary hacksaw blade may disposed lose its teeth after few strokes high-speed alloy steel blade 32 teeth per will cut through quite readily can filed bent slit brazed have obtaining 4130 tube local dealer supplies materials builders cus tom aircraft Another source supply scrap bin local airport As purchased 4130 tube has black oxide coating can re moved fine grade aluminum oxide cloth leaving polished surface accept solder brazing Standard outside diameters increments 062 25 through 50 in incre ments 125 beyond 50 Wall thickness varies 028 062 035 probably best suited purpose tubes intended give good tele scoping fit ordinarily insert brass bushings soldered place provide running fit between outer inner strut members sure good solder joint clean inner surface tube bright smoothness drill few small holes through tube spot bushing soldered Insert bushing Typical single-strut landing gear Bobs 12-year-old Piel Beryl has survived hundreds landings wheel Robart stuffed rubber foam Bottom view shows shockabsorbing construction aluminum scissors used control rotation sliding leg brake hose wire feeds models electric wheel brake 44 Model Aviation Radio Control Scale Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53019 Shock absorbing landing gear feature Francis McCrackens scratch-built Ryan PT-22 quarter-scale spans 90 weighs 178 lb uses Supertigre 2500 power Impact Engineering functional shock struts Jerday Inc have aluminum bodies stainless steel sliding posts/music wire axles Two styles wing nose gear coating solder paste flow molten solder through hole until begins appear other holes Use heavy soldering iron butane torch necessary certain se cure joint Brass tubing same dimensions wall thickness will weigh same steel lacks strength Aluminum tube equal weight would have three times wall thickness Aluminum difficult braze hardware store variety isnt satisfactory landing gears because high-tensile alloy anodized tough finish should removed before brazing Some modelers skilled art brazing aluminum have success us ing alloys such 2024 6061 contain some copper increased strength ease machining find ultimate example Scale modelers art shock struts seen Beechcraft King Air model Ramon Torres winner recent Scale Masters Tournament member team represent US next world championships Italy Ramons struts working parts machined nylon material has number ad vantages Its tough lightweight somewhat resilient also machines well other plastics would also serve such Delrin As full-size landing gears inner sliding member must restrained rotating some means prefer scissors linkage di rect copy prototype aircraft usually aluminum alloy forgings sim ulate type file machine parts 2024 aluminum alloy bar stock reasonable realism file marks can obliterated sandpaper sandblasting using tool Continued page 134 1 Drill hole No 18 drill size bulkhead firewall up 3/8 thick 2 Insert shaft Bulkhead Fitting through hole 3 Screw nut onto backside fitting Bulkhead Fittings Fourmost Bulkhead Fittin sare simple method feed fuel veni lines through solid bulkheads 4 Slip fuel vent tubes job done Bulkhead Fittings provide sealed tank compartment eliminate fuel line chafing Color coded easy identification Weight 1/2 gram Price 2 $295 No 121 FOURMOST PRODUCTS Size 3/32 4040 24th Avenue Forest Grove OR 97116 503 357-2732 Hundreds cowls kits plans Strong lightweight one-piece construction Exact duplicates manufacturers original Also radial cowls wheelpants Send Si 00 8-pg brochure Orcall 703-890-6017 9am-9 pm EDT phone orders information FIBERGLASS MDPtMARtBOXS3O Goodview VA 24095L~J April 1988 45 Bob discusses reason mounting lugs aluminum cylinder flange Gemini 120 twin broke after over 100 hours use thinks due metal fatigue caused combustion detonation machined nylon landing gear legs Ramon Torres prize-winning Beechcraft King Air have functioning shock absorbers SEE YOUR DEALER FIRST U can help you can order direct us sending full price plus $200 handling U fee 116W 19th St POBox 6 Higginsville MO 64037 call 816 584-7121U U U U U U U U U EU... EEEEEEUEE -7mount pressure tap goes answers own questions what would have told him trial error using tach largest expansion area pipe Actually theres pretty good chart MACS published pipes can use get very close right dimensionseven someone elses pipes advice tuning pipe Dont get greedy far better have pipe slightly too long too short Another lesson learned hard way mentions having rebend landing gear after flight because operates off rough field gears bend quite easily common problem Im surprised solu tion hasnt spread through hobby word-of-mouth Maybe metallurgist can ex plain appears after landing gear strut coils wound wire will bend fairly easily either direction solution problem works well ss put gear struts very hot 500 O 5500 F oven half hour quench cold water cant explain metallurgist should write please gear strut becomes much rigid Moving right along Toms questions mechanical retracts work well pneu matic retracts mechanical systems use two retract servos tn-gear setup prefer mechanical retracts because dont want fuss pressure tank control valve pressure tubing dont mind bother stalling pushrods Theres no question pneu matic retracts easier install problems maintenance over life airplane mechanical retracts years used retract servo wing operating three mechanical retracts worked fairly well time last airplane put retract servo wing main gears fuselage nose gear will never again use retract servo Two retract servos much easier stall reliable operate can afford extra two ounces airplane weight costs Tom asked another question bound interesting people landing gears bend easily Does battery drain become problem wheel working Obviously wants know battery can drain down wheel gets hung up wheel well wont go way up back down answer Yes Gears bind up will cause servo operate its stall current can easily severai hundred milliamperes current Since typically fly 500- 800milliampere-hour mAh battery packs doesnt take long drain down strongest battery perfectly pwpurrunu ur modeling Curtlss Robin 049 Engines -Channel RIC 41 Wingspan Electric Power Optional $2206 Oh 003 Very few lull Scale aicaff ideally suited model flight appealing old curtiss Robin horn spruce lines age beautifully proportioned rubber elect nC glow engines Easy end fun build trainerlibe performance Flyline Models catalog 500phone 17031 2730003 FLYLINE MODELS INC V PO Box 2136 FaIrfax Virginia 22e31 USA pack Tom mentioned reason used Rhom pneumatic retracts avoid airborne battery problems Its valid point Toms last question dilly What servos top gun fliers use aileron elevator might think would consen sus manufacturer isnt know Futaba PCM fliers use JR 401 501 ser vos Similarly JR fliers like Fu taba 130 131 servos real consensus should get top-of-the-line servo aileron elevator Franidy lot nuances servo performance top guns can de tect lost rest us RC Scale/Wischers Continued page 45 cleaning spark plugs looking uni form texture scalelike impression Light airplanes sometimes use steel stampings scissors members model can formed aluminum steel hard alloys aluminum dont form well likely crack along sharp bend Aluminum fresh mill can formed reasonably sharp radius year later will orange peel crack along bend Thin steel may better choice wheel axles made 156-indiameter music wire bent inserted lower telescoping part shock strut Lowtemperature solder used secure wire strut Strength solder ample because large area wetted molten solder last assembly step after high-heat brazed joints have made avoid changing tem per music wire would greatly weak en retractable gears retract mechanism always provides suitable structure mounting models wing fuselage Fixed landing gears inserted holes drilled hardwood blocks birch maple preferred spread load over large area possible through spr rounding balsa plywood Steel rods 156-in music wire can passed through hardwood blocks extended rearwardfor example additional hardwood cemented rear spar wing trying spread landing loads large area type construction has used stand hundreds landings Scale models landings perfectly executed shock absorbing struts dissipate impact load model may bounce back air will survive bounce again amount bounce determined springs side struts can hand-wound pur 134 Model Aviation A-J INTERCEPTOR RTF $695 $495 NOn rL$00* *00 $0 00 roe pO$flC$ OooofluuOrIftShoofte$oOOEhS AmUIJU AIRCRAFT COMPANY PO Box 68132 Portland OR 97268 I-U U U U U U U U U U U U U U U U U U U U IMS COMES * LIVE INDOOR MODEL DEMONSTRATIONS * BOAT POND * CAR TRACK * SWAP SHOP * GIANT RAFFLE popular demand International Modeler Show well known producing best model hobby show West coming ATLANTA April/May 1988 present same great model See latest products visit major manufacturers distributors Model Aircraft l Boats l Cars l Engines Radio Control Systems l Railroads ling Accessories STATIC DISPLAY COMPETITION IN MANY CATEGORIES INTERNATIONAL dflW MODELER 1o SHOW April 30 May 11988 Trade-Only Day Friday April 29 hobby show Southeast hun dred major model manufacturers over US have already registered exhibit premier annual extravaganza GEORGIA WORLD CONGRESS CENTER 285 International Blvd NW Atlanta GA ADMISSION Adults $500 Juniors 12 under $300 Children under six free accompanied adult PO Box 10127 Costa Mesa California 92627-0031 SATURDAY APRIL 30 1988 10 am 6 pm SUNDAY MAY 1 1988 10am 5am Phone 714 548-4700 chased local hardware store Spring making described April 1987 column MA Ready-made shock-absorbing landing gear struts time- labor-saver modeler prefers make own willing substitute cash effort Chicago Expo saw Impact Engineering struts made Jer day Inc struts made several sizes main nose gears models varying weight three 15 lb adaptable fixed retract gears Body diameters 375 50 axle sizes 156 312-in diameters struts scalelike appearance fea ture universal installation either fixed re tract gears means pair 6-32 setscrews Axles music wire pressed place ex ternal housing 6061-T6 aluminum alloy lower sliding member made stainless steel aligned upper housing means pin stainless scissors parts carry rotational loads address further information WS Jerday Inc 2100 Stonehill Ct Arlington TX 76012 Four-stroke engine problems Scale modelers will make effort hide disguise models power plant either inside close-fitting cowl hidden far rearward extension shaft Two-stroke engines forgiving enough outlive kind treatment exhaust two-stroke carries away excess heat means unburned fuel earliest lessons after beginning use four-stroke engines discovery high exhaust temperature its effect exhaust pipes mufflers first attempt homemade internally mounted muffler brazed aluminum construction re suited meltdown brazed joints Droplets melted aluminum fell inside cowl solidified rattled around give hint something adrift internally Another hint four-stroke exhaust very hot came discoloration plated ex haust tube convoluted copper pipe purloined household under-sink plumbing As further evidence charred wood ex haust pipe came within about / Direct contact wood kind balsa hardwood through heat sink must avoided because risk fire risk especially great tinder area being fanned unlimited supply oxygen prop blast past columns have recommended cowled engines provided close-fitting baf fles surrounding cylinder cooling fins made certain cooling air directed would good reasoned air would follow path least resistance through cowl outlet baffle necessary force air over engine practice full-size air-cooled engines have come conclusion baffle can close-fitting around cylinder fins models another source cool air carburetor intake particularly amount exhaust pipe also enclosed within cowl Full-size planes air-cooled engines have external duct carry cold air carburetor internal-combustion engines detonation phenomenon occurs within combustion chamber Despite high speed burning fuel cylinder normally still smooth processnot explosion Detonation re sults some factor interferes process smooth burning causes quick violent re action insteadin effect explosion has brought attention source detonation four-stroke engines gestion heated air induction system especially 2000 F above avoid incurring phenomenon detonation full-size air craft having supercharger intercooler mounted downstream supercharger before air enters carburetor used re duce air temperature before reaches cylinders Scale model having exhaust pipe en closed within engine cowl should sufficient air circulation carry away heat hot pipe duct should provided bring cooler air carburetor Most fourstroke single-cylinder engines have carburetors mounted behind engine non-Scale models exhaust externally mounted no problem heat-caused detonation Preignition subsequent detonation likely occur engine under load dur ing climb example know happens because clatter audible ground Enya 120 has resulted damage prop drive washer Enya has flats prop shaft engage close-fitting drive wash er matching flats hole After years operation flats inside aluminum drive washer have disappeared hole now almost round prop nut should tight ened often after flight two Detonation source abuse Detonation enemy four-stroke engine may survive hours some type failure can expected detonation overheated engine persists should learn recognize sound ground detected safest procedure close throt tle land problem will probably solved resetting needle valve slightly April 1988 135 NEW BULK Hardware Packs NEW Low-price glow-driver Power Panel NEW Catamaran Race Boat NEW RC Electric Hovercraft NEW Mini Sailwinch servo NEW Hitih performance nicads NEW High performance Speed Controls NEW Pushrods Name Street Address C ty CATALOG$750 Deducted 1st order over $2500 *U SA JAPAN V *oJ&Jfl . *GERMA1Y 1000s choose Solar rubber powered gliders copters scale lasercut diecut youcut rockets origami some wing span 6 feet ALL MADE OUT OF PAPER Limited number printed 18188423455PAPER AIRPLANES INTERNATIONAL1213822-9185 1521 Morningside Drive Burbank California91508USA richer setting will some power loss engine will run cooler Using tachometer will tell engine peaked should kept mind will run slightly leaner air Detonation backfiring can cause fatigue long run after years abuse Scale model example could lead broken crank shaft happened acquaintance Gemini 120 twin broken aluminum cylinder jacket after 100 hours operation cant certain detonation some time during engines life prime suspect problem loss power last flight model landed engine running errati cally cylinder perceived loose fracture occurred along sharply ma chined corner mounting flange cylinder jacket bolted crankcase full-size air-cooled engines corner always has large radius no radius Gemini cylinder jacket four lugs Geminis mounting flange remained intact prevent ed complete loss head cylinder valves surrounding cornfields new cylinder made lathe 2024-T35 1 aluminum alloy has machined radius mounting flange After inserting old cylinder liner adding piston cylinder heads engine has returned service running good new cylinder polished aluminum oth er black anodized Internally engine showed no wear no carbon gum buildup after 100 hours cas tor oil lubricant future will certainly aware detonation its devastating effect Four-stroke engines too expensive abused RC Soaring/Blakeslee Continued page 47 Blanchard wasnt fazed warmed up engines charged batteries flew DH 10 British bomber give us fix height haze Woody took second Ex pert Two-Meter What heck second Walt Good bad day flying after didnt get see Walt again main traction up RC World flying replica famous Guff pioneer RC plane lost track events later Sunday especially trophy awards kneedeep swamp water trying fish Tom Beck man s Sailaire out tallest oak tree Ive ever seen Later use small-bore shot gun shoot Out tree have reliable sources Ed Berton took first Open Expert Expert overall winner Shaun Ernst won Sportsman Open Rust Smith overall winner category Disaster Disney time between winch retriever break downs share impressions will make conversation far far future Nobody told us until Thirteenth Annual Tangerine New 12-volt winch Russell Keith Flight Line Systems sent photo description new winch offering sale Lets have Keith tell us about own words winch motor rebuilt GM metric-size unit does have shunted field limit speed setup uses less power amount torque produced allows motor smaller lighter shunted motor equal torque Also speed motor constant Under light load speed high load increases speed drops produce smooth launch variation speed helps keep constant tension line also helps prevent backlashes line goes slack motor speeds up keeping line taut may eliminate backlashes helps quite bit spools fabricated steel hub 1 /2-in diameter 6A long end plates 4-in thick diameter six inches end plates fitted onto shoulder gas-tungsten-arc-welded TIG makes very strong durable spool bushing Outer end spool shaft support current price $200 complete plus $10 shipping Anyone would like additional information may contact FLS PO Box 1502 Lewiston ME 04241 Need winch drum have longshaft Ford starter motor just need drum build own winch drums available World Cup Winch Products $7995 plus ship ping costs hub 3-in diameter end plates seven inches World Cup Bud Fox Jim Wichert also sells plans drum complete winch $20 plus postage Write 1791 Glenview St Simi Valley CA 93063 phone 805 526-3327 Customs courtesies Diablo Valley Club Northem California puts out very good newsletter Peter Rambo editor Peter recently printed clubs frequency control safety rules plus following list Customs Courtesies us have Sailpian ing some time tend regard things 136 Model Aviation over 150 NEW ITEMS YOU have never seen before ZMA Zip INTERNATIONAL INC a
Edition: Model Aviation - 1988/04
Page Numbers: 44, 45, 134, 135, 136
NEW NATS EVENT recent phone call Texas Scale modeler asked about competition event monster multiengined airplane weighed AMAs 40-lb limit Giant Scale Event 514 heard about newly proposed FAI event large Scale models have good news him February 1988 issue MA presented official schedule Virginia Nats now added event FAI Large Scale weight limit 55 lb addition engine total displacement top limit immense 61 cu could pair Quadra SOs three 35s maximum wing area 538 sq ft larger twin-engine man-carrying aero batic Cri-Cri France Imagine model 18ft span 3-ft chord powered pair Quadra 50s weighing 55 lb flying legally Nats Models class will static judged same manner other FA entrants except judging distance increased 165 ft nearest part model No bonuses will awarded flight score complexity model Maneuvers can enlarged beyond limits set smaller FAI models limits FAI has often accused living past Its strange Nats should adopting FAI event bring US competition up date larger heavier powerful airplanes Landing gears pet peeves single-strut landing gear Scale aircraft wobbles wiggles directions whenever model moves contact runway worst example occurs rough landing gear approaches complete collapse gear mounted softly avoid damage effect Scale appearance near-disaster produce landing gear strut looks acts scalelike manner need copy full-size construction actually goes along initial concept Scale modeling Dont invent just copy extra effort worth investment have now employed telescoping-tube principle six models gears have survived landings have easy models because shock absorbing qualities Smooth taxiing over rough surfaces has added benefit outer tube gear legs has 4130 chrome-molybdenum alloy steel material used fuselage framework en gine mounts landing gears full-size aircraft noted toughness yet surpris ingly easy manipulate using proper tools An ordinary hacksaw blade may disposed lose its teeth after few strokes high-speed alloy steel blade 32 teeth per will cut through quite readily can filed bent slit brazed have obtaining 4130 tube local dealer supplies materials builders cus tom aircraft Another source supply scrap bin local airport As purchased 4130 tube has black oxide coating can re moved fine grade aluminum oxide cloth leaving polished surface accept solder brazing Standard outside diameters increments 062 25 through 50 in incre ments 125 beyond 50 Wall thickness varies 028 062 035 probably best suited purpose tubes intended give good tele scoping fit ordinarily insert brass bushings soldered place provide running fit between outer inner strut members sure good solder joint clean inner surface tube bright smoothness drill few small holes through tube spot bushing soldered Insert bushing Typical single-strut landing gear Bobs 12-year-old Piel Beryl has survived hundreds landings wheel Robart stuffed rubber foam Bottom view shows shockabsorbing construction aluminum scissors used control rotation sliding leg brake hose wire feeds models electric wheel brake 44 Model Aviation Radio Control Scale Bob Dolly Wischer S-221 Lapham Peak Rd Delafield WI 53019 Shock absorbing landing gear feature Francis McCrackens scratch-built Ryan PT-22 quarter-scale spans 90 weighs 178 lb uses Supertigre 2500 power Impact Engineering functional shock struts Jerday Inc have aluminum bodies stainless steel sliding posts/music wire axles Two styles wing nose gear coating solder paste flow molten solder through hole until begins appear other holes Use heavy soldering iron butane torch necessary certain se cure joint Brass tubing same dimensions wall thickness will weigh same steel lacks strength Aluminum tube equal weight would have three times wall thickness Aluminum difficult braze hardware store variety isnt satisfactory landing gears because high-tensile alloy anodized tough finish should removed before brazing Some modelers skilled art brazing aluminum have success us ing alloys such 2024 6061 contain some copper increased strength ease machining find ultimate example Scale modelers art shock struts seen Beechcraft King Air model Ramon Torres winner recent Scale Masters Tournament member team represent US next world championships Italy Ramons struts working parts machined nylon material has number ad vantages Its tough lightweight somewhat resilient also machines well other plastics would also serve such Delrin As full-size landing gears inner sliding member must restrained rotating some means prefer scissors linkage di rect copy prototype aircraft usually aluminum alloy forgings sim ulate type file machine parts 2024 aluminum alloy bar stock reasonable realism file marks can obliterated sandpaper sandblasting using tool Continued page 134 1 Drill hole No 18 drill size bulkhead firewall up 3/8 thick 2 Insert shaft Bulkhead Fitting through hole 3 Screw nut onto backside fitting Bulkhead Fittings Fourmost Bulkhead Fittin sare simple method feed fuel veni lines through solid bulkheads 4 Slip fuel vent tubes job done Bulkhead Fittings provide sealed tank compartment eliminate fuel line chafing Color coded easy identification Weight 1/2 gram Price 2 $295 No 121 FOURMOST PRODUCTS Size 3/32 4040 24th Avenue Forest Grove OR 97116 503 357-2732 Hundreds cowls kits plans Strong lightweight one-piece construction Exact duplicates manufacturers original Also radial cowls wheelpants Send Si 00 8-pg brochure Orcall 703-890-6017 9am-9 pm EDT phone orders information FIBERGLASS MDPtMARtBOXS3O Goodview VA 24095L~J April 1988 45 Bob discusses reason mounting lugs aluminum cylinder flange Gemini 120 twin broke after over 100 hours use thinks due metal fatigue caused combustion detonation machined nylon landing gear legs Ramon Torres prize-winning Beechcraft King Air have functioning shock absorbers SEE YOUR DEALER FIRST U can help you can order direct us sending full price plus $200 handling U fee 116W 19th St POBox 6 Higginsville MO 64037 call 816 584-7121U U U U U U U U U EU... EEEEEEUEE -7mount pressure tap goes answers own questions what would have told him trial error using tach largest expansion area pipe Actually theres pretty good chart MACS published pipes can use get very close right dimensionseven someone elses pipes advice tuning pipe Dont get greedy far better have pipe slightly too long too short Another lesson learned hard way mentions having rebend landing gear after flight because operates off rough field gears bend quite easily common problem Im surprised solu tion hasnt spread through hobby word-of-mouth Maybe metallurgist can ex plain appears after landing gear strut coils wound wire will bend fairly easily either direction solution problem works well ss put gear struts very hot 500 O 5500 F oven half hour quench cold water cant explain metallurgist should write please gear strut becomes much rigid Moving right along Toms questions mechanical retracts work well pneu matic retracts mechanical systems use two retract servos tn-gear setup prefer mechanical retracts because dont want fuss pressure tank control valve pressure tubing dont mind bother stalling pushrods Theres no question pneu matic retracts easier install problems maintenance over life airplane mechanical retracts years used retract servo wing operating three mechanical retracts worked fairly well time last airplane put retract servo wing main gears fuselage nose gear will never again use retract servo Two retract servos much easier stall reliable operate can afford extra two ounces airplane weight costs Tom asked another question bound interesting people landing gears bend easily Does battery drain become problem wheel working Obviously wants know battery can drain down wheel gets hung up wheel well wont go way up back down answer Yes Gears bind up will cause servo operate its stall current can easily severai hundred milliamperes current Since typically fly 500- 800milliampere-hour mAh battery packs doesnt take long drain down strongest battery perfectly pwpurrunu ur modeling Curtlss Robin 049 Engines -Channel RIC 41 Wingspan Electric Power Optional $2206 Oh 003 Very few lull Scale aicaff ideally suited model flight appealing old curtiss Robin horn spruce lines age beautifully proportioned rubber elect nC glow engines Easy end fun build trainerlibe performance Flyline Models catalog 500phone 17031 2730003 FLYLINE MODELS INC V PO Box 2136 FaIrfax Virginia 22e31 USA pack Tom mentioned reason used Rhom pneumatic retracts avoid airborne battery problems Its valid point Toms last question dilly What servos top gun fliers use aileron elevator might think would consen sus manufacturer isnt know Futaba PCM fliers use JR 401 501 ser vos Similarly JR fliers like Fu taba 130 131 servos real consensus should get top-of-the-line servo aileron elevator Franidy lot nuances servo performance top guns can de tect lost rest us RC Scale/Wischers Continued page 45 cleaning spark plugs looking uni form texture scalelike impression Light airplanes sometimes use steel stampings scissors members model can formed aluminum steel hard alloys aluminum dont form well likely crack along sharp bend Aluminum fresh mill can formed reasonably sharp radius year later will orange peel crack along bend Thin steel may better choice wheel axles made 156-indiameter music wire bent inserted lower telescoping part shock strut Lowtemperature solder used secure wire strut Strength solder ample because large area wetted molten solder last assembly step after high-heat brazed joints have made avoid changing tem per music wire would greatly weak en retractable gears retract mechanism always provides suitable structure mounting models wing fuselage Fixed landing gears inserted holes drilled hardwood blocks birch maple preferred spread load over large area possible through spr rounding balsa plywood Steel rods 156-in music wire can passed through hardwood blocks extended rearwardfor example additional hardwood cemented rear spar wing trying spread landing loads large area type construction has used stand hundreds landings Scale models landings perfectly executed shock absorbing struts dissipate impact load model may bounce back air will survive bounce again amount bounce determined springs side struts can hand-wound pur 134 Model Aviation A-J INTERCEPTOR RTF $695 $495 NOn rL$00* *00 $0 00 roe pO$flC$ OooofluuOrIftShoofte$oOOEhS AmUIJU AIRCRAFT COMPANY PO Box 68132 Portland OR 97268 I-U U U U U U U U U U U U U U U U U U U U IMS COMES * LIVE INDOOR MODEL DEMONSTRATIONS * BOAT POND * CAR TRACK * SWAP SHOP * GIANT RAFFLE popular demand International Modeler Show well known producing best model hobby show West coming ATLANTA April/May 1988 present same great model See latest products visit major manufacturers distributors Model Aircraft l Boats l Cars l Engines Radio Control Systems l Railroads ling Accessories STATIC DISPLAY COMPETITION IN MANY CATEGORIES INTERNATIONAL dflW MODELER 1o SHOW April 30 May 11988 Trade-Only Day Friday April 29 hobby show Southeast hun dred major model manufacturers over US have already registered exhibit premier annual extravaganza GEORGIA WORLD CONGRESS CENTER 285 International Blvd NW Atlanta GA ADMISSION Adults $500 Juniors 12 under $300 Children under six free accompanied adult PO Box 10127 Costa Mesa California 92627-0031 SATURDAY APRIL 30 1988 10 am 6 pm SUNDAY MAY 1 1988 10am 5am Phone 714 548-4700 chased local hardware store Spring making described April 1987 column MA Ready-made shock-absorbing landing gear struts time- labor-saver modeler prefers make own willing substitute cash effort Chicago Expo saw Impact Engineering struts made Jer day Inc struts made several sizes main nose gears models varying weight three 15 lb adaptable fixed retract gears Body diameters 375 50 axle sizes 156 312-in diameters struts scalelike appearance fea ture universal installation either fixed re tract gears means pair 6-32 setscrews Axles music wire pressed place ex ternal housing 6061-T6 aluminum alloy lower sliding member made stainless steel aligned upper housing means pin stainless scissors parts carry rotational loads address further information WS Jerday Inc 2100 Stonehill Ct Arlington TX 76012 Four-stroke engine problems Scale modelers will make effort hide disguise models power plant either inside close-fitting cowl hidden far rearward extension shaft Two-stroke engines forgiving enough outlive kind treatment exhaust two-stroke carries away excess heat means unburned fuel earliest lessons after beginning use four-stroke engines discovery high exhaust temperature its effect exhaust pipes mufflers first attempt homemade internally mounted muffler brazed aluminum construction re suited meltdown brazed joints Droplets melted aluminum fell inside cowl solidified rattled around give hint something adrift internally Another hint four-stroke exhaust very hot came discoloration plated ex haust tube convoluted copper pipe purloined household under-sink plumbing As further evidence charred wood ex haust pipe came within about / Direct contact wood kind balsa hardwood through heat sink must avoided because risk fire risk especially great tinder area being fanned unlimited supply oxygen prop blast past columns have recommended cowled engines provided close-fitting baf fles surrounding cylinder cooling fins made certain cooling air directed would good reasoned air would follow path least resistance through cowl outlet baffle necessary force air over engine practice full-size air-cooled engines have come conclusion baffle can close-fitting around cylinder fins models another source cool air carburetor intake particularly amount exhaust pipe also enclosed within cowl Full-size planes air-cooled engines have external duct carry cold air carburetor internal-combustion engines detonation phenomenon occurs within combustion chamber Despite high speed burning fuel cylinder normally still smooth processnot explosion Detonation re sults some factor interferes process smooth burning causes quick violent re action insteadin effect explosion has brought attention source detonation four-stroke engines gestion heated air induction system especially 2000 F above avoid incurring phenomenon detonation full-size air craft having supercharger intercooler mounted downstream supercharger before air enters carburetor used re duce air temperature before reaches cylinders Scale model having exhaust pipe en closed within engine cowl should sufficient air circulation carry away heat hot pipe duct should provided bring cooler air carburetor Most fourstroke single-cylinder engines have carburetors mounted behind engine non-Scale models exhaust externally mounted no problem heat-caused detonation Preignition subsequent detonation likely occur engine under load dur ing climb example know happens because clatter audible ground Enya 120 has resulted damage prop drive washer Enya has flats prop shaft engage close-fitting drive wash er matching flats hole After years operation flats inside aluminum drive washer have disappeared hole now almost round prop nut should tight ened often after flight two Detonation source abuse Detonation enemy four-stroke engine may survive hours some type failure can expected detonation overheated engine persists should learn recognize sound ground detected safest procedure close throt tle land problem will probably solved resetting needle valve slightly April 1988 135 NEW BULK Hardware Packs NEW Low-price glow-driver Power Panel NEW Catamaran Race Boat NEW RC Electric Hovercraft NEW Mini Sailwinch servo NEW Hitih performance nicads NEW High performance Speed Controls NEW Pushrods Name Street Address C ty CATALOG$750 Deducted 1st order over $2500 *U SA JAPAN V *oJ&Jfl . *GERMA1Y 1000s choose Solar rubber powered gliders copters scale lasercut diecut youcut rockets origami some wing span 6 feet ALL MADE OUT OF PAPER Limited number printed 18188423455PAPER AIRPLANES INTERNATIONAL1213822-9185 1521 Morningside Drive Burbank California91508USA richer setting will some power loss engine will run cooler Using tachometer will tell engine peaked should kept mind will run slightly leaner air Detonation backfiring can cause fatigue long run after years abuse Scale model example could lead broken crank shaft happened acquaintance Gemini 120 twin broken aluminum cylinder jacket after 100 hours operation cant certain detonation some time during engines life prime suspect problem loss power last flight model landed engine running errati cally cylinder perceived loose fracture occurred along sharply ma chined corner mounting flange cylinder jacket bolted crankcase full-size air-cooled engines corner always has large radius no radius Gemini cylinder jacket four lugs Geminis mounting flange remained intact prevent ed complete loss head cylinder valves surrounding cornfields new cylinder made lathe 2024-T35 1 aluminum alloy has machined radius mounting flange After inserting old cylinder liner adding piston cylinder heads engine has returned service running good new cylinder polished aluminum oth er black anodized Internally engine showed no wear no carbon gum buildup after 100 hours cas tor oil lubricant future will certainly aware detonation its devastating effect Four-stroke engines too expensive abused RC Soaring/Blakeslee Continued page 47 Blanchard wasnt fazed warmed up engines charged batteries flew DH 10 British bomber give us fix height haze Woody took second Ex pert Two-Meter What heck second Walt Good bad day flying after didnt get see Walt again main traction up RC World flying replica famous Guff pioneer RC plane lost track events later Sunday especially trophy awards kneedeep swamp water trying fish Tom Beck man s Sailaire out tallest oak tree Ive ever seen Later use small-bore shot gun shoot Out tree have reliable sources Ed Berton took first Open Expert Expert overall winner Shaun Ernst won Sportsman Open Rust Smith overall winner category Disaster Disney time between winch retriever break downs share impressions will make conversation far far future Nobody told us until Thirteenth Annual Tangerine New 12-volt winch Russell Keith Flight Line Systems sent photo description new winch offering sale Lets have Keith tell us about own words winch motor rebuilt GM metric-size unit does have shunted field limit speed setup uses less power amount torque produced allows motor smaller lighter shunted motor equal torque Also speed motor constant Under light load speed high load increases speed drops produce smooth launch variation speed helps keep constant tension line also helps prevent backlashes line goes slack motor speeds up keeping line taut may eliminate backlashes helps quite bit spools fabricated steel hub 1 /2-in diameter 6A long end plates 4-in thick diameter six inches end plates fitted onto shoulder gas-tungsten-arc-welded TIG makes very strong durable spool bushing Outer end spool shaft support current price $200 complete plus $10 shipping Anyone would like additional information may contact FLS PO Box 1502 Lewiston ME 04241 Need winch drum have longshaft Ford starter motor just need drum build own winch drums available World Cup Winch Products $7995 plus ship ping costs hub 3-in diameter end plates seven inches World Cup Bud Fox Jim Wichert also sells plans drum complete winch $20 plus postage Write 1791 Glenview St Simi Valley CA 93063 phone 805 526-3327 Customs courtesies Diablo Valley Club Northem California puts out very good newsletter Peter Rambo editor Peter recently printed clubs frequency control safety rules plus following list Customs Courtesies us have Sailpian ing some time tend regard things 136 Model Aviation over 150 NEW ITEMS YOU have never seen before ZMA Zip INTERNATIONAL INC a