OLD TIMERS Clarence Haught THE BIG cover up few columns back dis cussed some basic fundamentals OldTimer construction newcomers hobby Hopefully now have com pleted structure ready cover trendy thing today use plastic iron-on coverings get air quickly withcut smelling up house dope fumes may attractive alternative plastic just doesnt look right vintage model keeping spirit OldTimers traditional finish appropriate dont want prejudice against plastics experience AMA-class Free Flight models has good may have heard argued covering does contribute strength structure some validity theory readily apparent covering does add torsional rigidity find dope-and-paper dope-andfabric finishes far superior respect less susceptible temperature changes resultant warps have convinced apply conven tional covering begin giving structure thorough sanding followed two coats fullstrength clear dope sanded between coats remove raised grain members cover ing bonded choices covering materials include papers fabrics Papers include Japanese tissue silkspan three progressively heavier grades 00 very light GM medium 5GM heavy Fabrics include Japanese silk light Chinese silk medium rayon heavy other suitable light fabrics neighborhood sewing center choosing covering keep mind size model strength needed weight its expected life span Old-Timers tend live longer modern cousins can outlast paper covering job Fabric covering lasts forever resistant puncture wounds minor crash damage Japanese tissue very light lacks strength other choices quite strong applied double second layer applied after first has couple coats dope Japanese tissue applied dry stuck down mixture 75% thinner 25% dope applied through tissue softening dope previously applied structure Any compound curves must covered small pieces shrinks well upon applicated sprayed water mist plastic household sprayer Japanese tissue best re stricted use models up size small Class B ships comes multitude colors commonly used decorative trim numbers Just cut out shape desired stick down brushing thinner between second third coat dope old standby silkspan should applied wet Lay suitable piece structure dry wet spray bottle Pull out wrinkles Lift edge time stick down clear dope dry trim razor blade sandpaper apply dope like 00grade tail surfaces GM wings 5GM fuselages SGM takes lot dope seal five eight coats provides good protection oil routine handling Silkspan comes white can dipped clothing dye blotted between newspaper immediately prior application takes little care ensure color uniformity works well paper should applied its grain spanwise wings minimize sag between ribs Determine grain tearing small piece tears evenly grain Fabric covering should also applied wet handles very similar silkspan works around corners well due its weave Ive good luck covering bigger ships sewing shop product called Acetate Sheath dress lining material quite inexpensive comes colors heavy very strong use fuselages mainly use lighter fabrics flying surfaces have heard reports some sewing fabrics dissolve dope applied Better run test sample first Finally subject covering materials Coverite products include Silkspun Coverite extremely tough shows good promise yet retains traditional look paper cover ing regular Coverite good fabric covering allows iron-on techniques finishes rapidly minimum dope paint actual finish has choice nitrate butyrate dope nitrate dope epoxy paints Gasoline/oil fuel mixtures used igni tion engines harmful dope finishes Nitrate dopes shrink much butyrate say nitrate dopes continue shrink life finish butyrates tend nitrate quite flammable Ive seen some models burned up field result engine flooding backfire Butyrate will burn least fire resistant purchase dope local airport much thicker sold modeling pur poses allows thinning suit application Continued page 109 54 Model Aviation Allan Heinrich Pomona CA prepares FOO-2-U flight powered Remco replica Forster 29 Allan has some commercial modeling interestshe produces blended Aerodyne fuels also handles non-taughtening nitrate dope thinner Clarence didni gex mis moasiers name oui knows hes srom 1-resno ma snows events Seen Bill preparing Super Cyclone-powered MK 1 umlpper Model features silkspan covering full paint job propeller pitched up slightly 10 1 0 above established pitch center section should pitched down slightly station prop actually correct 75% station pitch measured other stations little above little below geometric pitch net effect slightly increase average pitch prop manufacturer must experiment pitch distribution stick props designs will know prop will perform Efficiency constantly changing rpm Model props turn such high rpm have efficiencies 40% 50% am still confused two components prop thrust think thrust generated both upper face prop approximately what percentage thrust con tributed eachand what speeds want thank time effort put column reply Dont know what want letter Ive got good idea would appreciate comments would care make comments column will short due lack space next month Ill talk about percentage thrust generated two sides prop Basically agree everything Bill Cassidy alleged have said alluded differences way prop manufacturers made products April 1980 column As far what want complex controversial letters can see what did Others like same other subjects welcome encour aged general interest Ill see get printed Ron Van Putte 111 Sleepy Oaks Rd Fort Walton Beach FL 32548 FF Old-Timers/Haught Continued page 54 like use nearly full-strength adhering covering Acrylic lacquer thinner obtainable automotive supply house works well either nitrate butyrate dope Acrylic lacquer thinner comes three grades cleanup thinner works fine cheap does produce high gloss does soften previous coats great degree light-penetration thinner does soften some high gloss thinner has deep penetration Various brand names available have basic grades Butyrate dope may applied over nitrate dope vice versa Some builders begin finish nitrate complete epoxy paints either clear pigmented personally like keep finishes pure throughout easier patch repair basic dope finishes Initial coats dope should brushed ensure good bond Later coats may sprayed good ventilation available Brushing first coat fabric particularly silk can problem dope tends brushed through cloth runs down inside creating blisters fabric problem can virtually eliminated applying dope fo new foam brushes Just dip brush dope drag across fabric lays film dope surface will soak enough good bond creating blister effect Dont go over wet areasjust overlap slightly pass brush About five coats dope should provide serviceable finish depend ing course much dope thinned like bring up light gloss stop Less 77Dave Dlatt iviodels Inc Air cylinder 5/8 bore New design Y-LOCK provides positive lock UP asd DOWN Mt super-tough Only 1 3/8 high fits airfoilCAPRON Low profile asd overall compact size Retraction angle t5 9O --specify ordering Lz fl7 DEVELOP Massive legs--i /2 diameter alloy 1* spring shock-absorbing bottom end L included REFINE EXPAND Experience RLG System customers ourselves over past 2 years has resulted numerous mechanical revisions improvements have incorporated fanfare significant result has highly refined retract system large models io 30 lbs Besides being used own 1/5 scale kits recommended Bud Nosen P-Si P47 Vito Fomeo big Sea Fury several others versatility system has expanded several ways have choice 850 900 retraction angle choice leg-under-cylinder leg-away-from-cylin der offer free leaflet describing simple modification up-and-twist Corsair style operation another showing noseleg modification Different coils available unique oleo shock-legs handle various weights model instructions now include details tail wheel hookup Sure Piper Cubs nice youre thinking about large-scale model retract-gear ship Dave Platt RLG System has made designs possibleSystem Price $12900 Outfit Includes 2 main units shock-legs air tank switcher pressure indicator tubing etc booklet Optional extras -- pump speed reducers extra air tanks Dave Platt products available dtrectlt/ manufacturer ONLY Send check Money Order Visa MasterCard number C 0 D orders also accepted /97DlattVISA j6951 Northwest 15th Avenue oaveEvuodels Fort Lauderdale Florida 33309 call 305/587-4861 evenings AIRO Meets SAM RC Antique & Old Timer events School Yard trainer mu —VVviijDELIts size weight make secellent chotne ton mire parts formed shape II Contains complete hardware package including miniB 8~yv R D G IiI E adisotable puohrod connectors screws blind nets Balsa wheel kit 4 wheel halves plastrc bearings washers wheel retainers pro-fabrication material selection otthe Mike surpasses Tyro Playboy Senior sPEcIFIcATIONS mnt5vanaO5 OveAii Lengthn mint chora70 Mn Sen wgt75 inns Aea sq Snorne sun -os PLAYBOY SENIOR Still Available $49 95 plus 3 00 freight tr handling Price S2895 Hobby Dealer ordering direcn please add $250 freight handling & insurance California residents add 6% Salon Tax Manufactured Tyro Models Designed no Flyll 1930 EDGEWOOD DR. PO BOX 11511 PALO ALTO CA 94306 415 856-7781 uary 1981 109 SCALE WHE RADIO CONTROL ROL-UNE 0 _ 0 0 VINTAGESMOOTHGOLDEN AGENEW sizes2YzCONTOURsizes21/iBALLOON 343/"23/43431/a 1334134132/z41/2 11443/i11/4311/443/i34514 11/251/24/z1hz53 1ls6/21451/41s61/2 ELS FREE-FLIGHT SCALE PILOTS CYUNDERS ENGINE KITS MACHINE GUN KITS PLASTIC DISPLAY MODELS EROS INTh SEND $1 FOR COMPLETE ILLUSTRATED CATALOG ___________________ DEPT MA PAWNEE ST SAN MARCOS CA 9 INTRODUCING Tile American RJL K6I R/C ENGINE RJL Industries now produces renowned engine formerly manufactured Kraft Systems Inc schnuerle ported 61 cubic inch engine provides easy starting high performance longevity Produced finest materials workmanship quality assurance youll proud have aircraft powered K61 FEATURES INCLUDE Schnuerle Ports Boost Port Double Ball Bearings Forged Alloy Piston & Con Rod Bushed Connecting Rod 0- ring Sealed Back Cover 16 HP 15500 RPM SUGGESTED RETAIL $13995 Muffler Included Send Free Catalog Today R J L INDUSTRIES P0 Box 5654 Pasadena CA 91107 1831 Business Center Dr Duarte CA 91010 allows oil soaking begins invite warps Incidentally have just learned R 1 Mikkelson producing nitrate dope red yellow blue orange black white distil bution Old Timer Models PO Box 913 Westminster CA 92683 last word Dont stink up house just before company comes may understand reference dope Clarence Haught Rt 5 Box 16 CouerdAlene ID 83814 i 213/359-0016 RC Helicopters/Chesney Continued page 33 sponses As someone told few years back might get trouble faster can get out trouble faster too course Heli copter will respond differently pilots capabilities will vary best rule may well fly way comes out box Thought might enjoy knowing few times snows down South photos shows mere snow cant stop dedi cated chopper pilot like W R Hartness Sanford NC Also special tip winter fliers Lloyd Wheelerwatch out rotor blade icingSee next month Dave Chesney 9 Box 621A Greensboro NC 27409 RC Soaring/Pruss Continued page 31 place fastest time around 76-kilometer 472-mi Great Race course race Pat Flinn Greater Detroit Soaring Hiking Society won last year flight 304 miles November MA challenge open AMA chartered clubs further formation may obtained sending stamped self-addressed business envelope address below Good Lift Dan Pruss RR 2 Box 49D Plainfield IL 60544 RC Scale/Wischers Continued page 35 Early morning wind light Brian Allen flew Gossamer Albatross misfortune Wittman Airport day pleasure introduction also met Brians parents source modesty equanimity became apparent Scale race-plane buffs fullsize reproductions Gee Bee Z Travelair Mystery Ship Laird Super Solution along Jimmy Doolittle flew original Laird Bendix Thompson Trophy races Two weeks after convention again Wittman field attended three days World Aerobatic Championships Forty-two men nine women 10 countries included competition about 20 planes use several pilots taking turns flying some planes Pitts 5-1 S-2s common US designs along Christen Eagle Leo Loudenslagers winning Laser 200 German team used Zlin SOL France three CAP 20s CAP 21 ASA 200 CAP 20 fuselage tapered wing place usual semi-elliptical planform aerobatic types ideal Scale projects some already available kit form CAP 20 featured construction article March 1980 issue Model Aviation United States swept first three places both mens womens divisions reader trend toward 1/5-scale practical alternative Giant Scale seems gaining foothold thought letter Louie Scribner contained material general interest Nats chance visit Springfield MAC field Donnelsville OH watched several fellows flying new Old-Timers seven-foot-span range powered 05 60 4-cycle engines impressed quiet engines low rpms floating ability planes occurred build Sport Scale might build Piper 1-3 along same lines would fly slowly smoothly calm air using same 05 60 engine might add Im interested belt drives chain-saw engines Giant Scale Ive already built Sig J-3 turned out rather nicely Im considering scaling Sig plans up 117 times 1/6-scale handle 05 60 engine seems have about power good 40 14-6 7500 rpm Obviously -scale too much 1/5-scale might right would produce following numbers Span 845-in chord 12-in wing thickness 1-5/16-in overall length 52-in area Continued page 112 110 Model Aviation 0 SAFE FLYING IS NO ACCIDENT
Edition: Model Aviation - 1981/02
Page Numbers: 54, 109, 110
OLD TIMERS Clarence Haught THE BIG cover up few columns back dis cussed some basic fundamentals OldTimer construction newcomers hobby Hopefully now have com pleted structure ready cover trendy thing today use plastic iron-on coverings get air quickly withcut smelling up house dope fumes may attractive alternative plastic just doesnt look right vintage model keeping spirit OldTimers traditional finish appropriate dont want prejudice against plastics experience AMA-class Free Flight models has good may have heard argued covering does contribute strength structure some validity theory readily apparent covering does add torsional rigidity find dope-and-paper dope-andfabric finishes far superior respect less susceptible temperature changes resultant warps have convinced apply conven tional covering begin giving structure thorough sanding followed two coats fullstrength clear dope sanded between coats remove raised grain members cover ing bonded choices covering materials include papers fabrics Papers include Japanese tissue silkspan three progressively heavier grades 00 very light GM medium 5GM heavy Fabrics include Japanese silk light Chinese silk medium rayon heavy other suitable light fabrics neighborhood sewing center choosing covering keep mind size model strength needed weight its expected life span Old-Timers tend live longer modern cousins can outlast paper covering job Fabric covering lasts forever resistant puncture wounds minor crash damage Japanese tissue very light lacks strength other choices quite strong applied double second layer applied after first has couple coats dope Japanese tissue applied dry stuck down mixture 75% thinner 25% dope applied through tissue softening dope previously applied structure Any compound curves must covered small pieces shrinks well upon applicated sprayed water mist plastic household sprayer Japanese tissue best re stricted use models up size small Class B ships comes multitude colors commonly used decorative trim numbers Just cut out shape desired stick down brushing thinner between second third coat dope old standby silkspan should applied wet Lay suitable piece structure dry wet spray bottle Pull out wrinkles Lift edge time stick down clear dope dry trim razor blade sandpaper apply dope like 00grade tail surfaces GM wings 5GM fuselages SGM takes lot dope seal five eight coats provides good protection oil routine handling Silkspan comes white can dipped clothing dye blotted between newspaper immediately prior application takes little care ensure color uniformity works well paper should applied its grain spanwise wings minimize sag between ribs Determine grain tearing small piece tears evenly grain Fabric covering should also applied wet handles very similar silkspan works around corners well due its weave Ive good luck covering bigger ships sewing shop product called Acetate Sheath dress lining material quite inexpensive comes colors heavy very strong use fuselages mainly use lighter fabrics flying surfaces have heard reports some sewing fabrics dissolve dope applied Better run test sample first Finally subject covering materials Coverite products include Silkspun Coverite extremely tough shows good promise yet retains traditional look paper cover ing regular Coverite good fabric covering allows iron-on techniques finishes rapidly minimum dope paint actual finish has choice nitrate butyrate dope nitrate dope epoxy paints Gasoline/oil fuel mixtures used igni tion engines harmful dope finishes Nitrate dopes shrink much butyrate say nitrate dopes continue shrink life finish butyrates tend nitrate quite flammable Ive seen some models burned up field result engine flooding backfire Butyrate will burn least fire resistant purchase dope local airport much thicker sold modeling pur poses allows thinning suit application Continued page 109 54 Model Aviation Allan Heinrich Pomona CA prepares FOO-2-U flight powered Remco replica Forster 29 Allan has some commercial modeling interestshe produces blended Aerodyne fuels also handles non-taughtening nitrate dope thinner Clarence didni gex mis moasiers name oui knows hes srom 1-resno ma snows events Seen Bill preparing Super Cyclone-powered MK 1 umlpper Model features silkspan covering full paint job propeller pitched up slightly 10 1 0 above established pitch center section should pitched down slightly station prop actually correct 75% station pitch measured other stations little above little below geometric pitch net effect slightly increase average pitch prop manufacturer must experiment pitch distribution stick props designs will know prop will perform Efficiency constantly changing rpm Model props turn such high rpm have efficiencies 40% 50% am still confused two components prop thrust think thrust generated both upper face prop approximately what percentage thrust con tributed eachand what speeds want thank time effort put column reply Dont know what want letter Ive got good idea would appreciate comments would care make comments column will short due lack space next month Ill talk about percentage thrust generated two sides prop Basically agree everything Bill Cassidy alleged have said alluded differences way prop manufacturers made products April 1980 column As far what want complex controversial letters can see what did Others like same other subjects welcome encour aged general interest Ill see get printed Ron Van Putte 111 Sleepy Oaks Rd Fort Walton Beach FL 32548 FF Old-Timers/Haught Continued page 54 like use nearly full-strength adhering covering Acrylic lacquer thinner obtainable automotive supply house works well either nitrate butyrate dope Acrylic lacquer thinner comes three grades cleanup thinner works fine cheap does produce high gloss does soften previous coats great degree light-penetration thinner does soften some high gloss thinner has deep penetration Various brand names available have basic grades Butyrate dope may applied over nitrate dope vice versa Some builders begin finish nitrate complete epoxy paints either clear pigmented personally like keep finishes pure throughout easier patch repair basic dope finishes Initial coats dope should brushed ensure good bond Later coats may sprayed good ventilation available Brushing first coat fabric particularly silk can problem dope tends brushed through cloth runs down inside creating blisters fabric problem can virtually eliminated applying dope fo new foam brushes Just dip brush dope drag across fabric lays film dope surface will soak enough good bond creating blister effect Dont go over wet areasjust overlap slightly pass brush About five coats dope should provide serviceable finish depend ing course much dope thinned like bring up light gloss stop Less 77Dave Dlatt iviodels Inc Air cylinder 5/8 bore New design Y-LOCK provides positive lock UP asd DOWN Mt super-tough Only 1 3/8 high fits airfoilCAPRON Low profile asd overall compact size Retraction angle t5 9O --specify ordering Lz fl7 DEVELOP Massive legs--i /2 diameter alloy 1* spring shock-absorbing bottom end L included REFINE EXPAND Experience RLG System customers ourselves over past 2 years has resulted numerous mechanical revisions improvements have incorporated fanfare significant result has highly refined retract system large models io 30 lbs Besides being used own 1/5 scale kits recommended Bud Nosen P-Si P47 Vito Fomeo big Sea Fury several others versatility system has expanded several ways have choice 850 900 retraction angle choice leg-under-cylinder leg-away-from-cylin der offer free leaflet describing simple modification up-and-twist Corsair style operation another showing noseleg modification Different coils available unique oleo shock-legs handle various weights model instructions now include details tail wheel hookup Sure Piper Cubs nice youre thinking about large-scale model retract-gear ship Dave Platt RLG System has made designs possibleSystem Price $12900 Outfit Includes 2 main units shock-legs air tank switcher pressure indicator tubing etc booklet Optional extras -- pump speed reducers extra air tanks Dave Platt products available dtrectlt/ manufacturer ONLY Send check Money Order Visa MasterCard number C 0 D orders also accepted /97DlattVISA j6951 Northwest 15th Avenue oaveEvuodels Fort Lauderdale Florida 33309 call 305/587-4861 evenings AIRO Meets SAM RC Antique & Old Timer events School Yard trainer mu —VVviijDELIts size weight make secellent chotne ton mire parts formed shape II Contains complete hardware package including miniB 8~yv R D G IiI E adisotable puohrod connectors screws blind nets Balsa wheel kit 4 wheel halves plastrc bearings washers wheel retainers pro-fabrication material selection otthe Mike surpasses Tyro Playboy Senior sPEcIFIcATIONS mnt5vanaO5 OveAii Lengthn mint chora70 Mn Sen wgt75 inns Aea sq Snorne sun -os PLAYBOY SENIOR Still Available $49 95 plus 3 00 freight tr handling Price S2895 Hobby Dealer ordering direcn please add $250 freight handling & insurance California residents add 6% Salon Tax Manufactured Tyro Models Designed no Flyll 1930 EDGEWOOD DR. PO BOX 11511 PALO ALTO CA 94306 415 856-7781 uary 1981 109 SCALE WHE RADIO CONTROL ROL-UNE 0 _ 0 0 VINTAGESMOOTHGOLDEN AGENEW sizes2YzCONTOURsizes21/iBALLOON 343/"23/43431/a 1334134132/z41/2 11443/i11/4311/443/i34514 11/251/24/z1hz53 1ls6/21451/41s61/2 ELS FREE-FLIGHT SCALE PILOTS CYUNDERS ENGINE KITS MACHINE GUN KITS PLASTIC DISPLAY MODELS EROS INTh SEND $1 FOR COMPLETE ILLUSTRATED CATALOG ___________________ DEPT MA PAWNEE ST SAN MARCOS CA 9 INTRODUCING Tile American RJL K6I R/C ENGINE RJL Industries now produces renowned engine formerly manufactured Kraft Systems Inc schnuerle ported 61 cubic inch engine provides easy starting high performance longevity Produced finest materials workmanship quality assurance youll proud have aircraft powered K61 FEATURES INCLUDE Schnuerle Ports Boost Port Double Ball Bearings Forged Alloy Piston & Con Rod Bushed Connecting Rod 0- ring Sealed Back Cover 16 HP 15500 RPM SUGGESTED RETAIL $13995 Muffler Included Send Free Catalog Today R J L INDUSTRIES P0 Box 5654 Pasadena CA 91107 1831 Business Center Dr Duarte CA 91010 allows oil soaking begins invite warps Incidentally have just learned R 1 Mikkelson producing nitrate dope red yellow blue orange black white distil bution Old Timer Models PO Box 913 Westminster CA 92683 last word Dont stink up house just before company comes may understand reference dope Clarence Haught Rt 5 Box 16 CouerdAlene ID 83814 i 213/359-0016 RC Helicopters/Chesney Continued page 33 sponses As someone told few years back might get trouble faster can get out trouble faster too course Heli copter will respond differently pilots capabilities will vary best rule may well fly way comes out box Thought might enjoy knowing few times snows down South photos shows mere snow cant stop dedi cated chopper pilot like W R Hartness Sanford NC Also special tip winter fliers Lloyd Wheelerwatch out rotor blade icingSee next month Dave Chesney 9 Box 621A Greensboro NC 27409 RC Soaring/Pruss Continued page 31 place fastest time around 76-kilometer 472-mi Great Race course race Pat Flinn Greater Detroit Soaring Hiking Society won last year flight 304 miles November MA challenge open AMA chartered clubs further formation may obtained sending stamped self-addressed business envelope address below Good Lift Dan Pruss RR 2 Box 49D Plainfield IL 60544 RC Scale/Wischers Continued page 35 Early morning wind light Brian Allen flew Gossamer Albatross misfortune Wittman Airport day pleasure introduction also met Brians parents source modesty equanimity became apparent Scale race-plane buffs fullsize reproductions Gee Bee Z Travelair Mystery Ship Laird Super Solution along Jimmy Doolittle flew original Laird Bendix Thompson Trophy races Two weeks after convention again Wittman field attended three days World Aerobatic Championships Forty-two men nine women 10 countries included competition about 20 planes use several pilots taking turns flying some planes Pitts 5-1 S-2s common US designs along Christen Eagle Leo Loudenslagers winning Laser 200 German team used Zlin SOL France three CAP 20s CAP 21 ASA 200 CAP 20 fuselage tapered wing place usual semi-elliptical planform aerobatic types ideal Scale projects some already available kit form CAP 20 featured construction article March 1980 issue Model Aviation United States swept first three places both mens womens divisions reader trend toward 1/5-scale practical alternative Giant Scale seems gaining foothold thought letter Louie Scribner contained material general interest Nats chance visit Springfield MAC field Donnelsville OH watched several fellows flying new Old-Timers seven-foot-span range powered 05 60 4-cycle engines impressed quiet engines low rpms floating ability planes occurred build Sport Scale might build Piper 1-3 along same lines would fly slowly smoothly calm air using same 05 60 engine might add Im interested belt drives chain-saw engines Giant Scale Ive already built Sig J-3 turned out rather nicely Im considering scaling Sig plans up 117 times 1/6-scale handle 05 60 engine seems have about power good 40 14-6 7500 rpm Obviously -scale too much 1/5-scale might right would produce following numbers Span 845-in chord 12-in wing thickness 1-5/16-in overall length 52-in area Continued page 112 110 Model Aviation 0 SAFE FLYING IS NO ACCIDENT
Edition: Model Aviation - 1981/02
Page Numbers: 54, 109, 110
OLD TIMERS Clarence Haught THE BIG cover up few columns back dis cussed some basic fundamentals OldTimer construction newcomers hobby Hopefully now have com pleted structure ready cover trendy thing today use plastic iron-on coverings get air quickly withcut smelling up house dope fumes may attractive alternative plastic just doesnt look right vintage model keeping spirit OldTimers traditional finish appropriate dont want prejudice against plastics experience AMA-class Free Flight models has good may have heard argued covering does contribute strength structure some validity theory readily apparent covering does add torsional rigidity find dope-and-paper dope-andfabric finishes far superior respect less susceptible temperature changes resultant warps have convinced apply conven tional covering begin giving structure thorough sanding followed two coats fullstrength clear dope sanded between coats remove raised grain members cover ing bonded choices covering materials include papers fabrics Papers include Japanese tissue silkspan three progressively heavier grades 00 very light GM medium 5GM heavy Fabrics include Japanese silk light Chinese silk medium rayon heavy other suitable light fabrics neighborhood sewing center choosing covering keep mind size model strength needed weight its expected life span Old-Timers tend live longer modern cousins can outlast paper covering job Fabric covering lasts forever resistant puncture wounds minor crash damage Japanese tissue very light lacks strength other choices quite strong applied double second layer applied after first has couple coats dope Japanese tissue applied dry stuck down mixture 75% thinner 25% dope applied through tissue softening dope previously applied structure Any compound curves must covered small pieces shrinks well upon applicated sprayed water mist plastic household sprayer Japanese tissue best re stricted use models up size small Class B ships comes multitude colors commonly used decorative trim numbers Just cut out shape desired stick down brushing thinner between second third coat dope old standby silkspan should applied wet Lay suitable piece structure dry wet spray bottle Pull out wrinkles Lift edge time stick down clear dope dry trim razor blade sandpaper apply dope like 00grade tail surfaces GM wings 5GM fuselages SGM takes lot dope seal five eight coats provides good protection oil routine handling Silkspan comes white can dipped clothing dye blotted between newspaper immediately prior application takes little care ensure color uniformity works well paper should applied its grain spanwise wings minimize sag between ribs Determine grain tearing small piece tears evenly grain Fabric covering should also applied wet handles very similar silkspan works around corners well due its weave Ive good luck covering bigger ships sewing shop product called Acetate Sheath dress lining material quite inexpensive comes colors heavy very strong use fuselages mainly use lighter fabrics flying surfaces have heard reports some sewing fabrics dissolve dope applied Better run test sample first Finally subject covering materials Coverite products include Silkspun Coverite extremely tough shows good promise yet retains traditional look paper cover ing regular Coverite good fabric covering allows iron-on techniques finishes rapidly minimum dope paint actual finish has choice nitrate butyrate dope nitrate dope epoxy paints Gasoline/oil fuel mixtures used igni tion engines harmful dope finishes Nitrate dopes shrink much butyrate say nitrate dopes continue shrink life finish butyrates tend nitrate quite flammable Ive seen some models burned up field result engine flooding backfire Butyrate will burn least fire resistant purchase dope local airport much thicker sold modeling pur poses allows thinning suit application Continued page 109 54 Model Aviation Allan Heinrich Pomona CA prepares FOO-2-U flight powered Remco replica Forster 29 Allan has some commercial modeling interestshe produces blended Aerodyne fuels also handles non-taughtening nitrate dope thinner Clarence didni gex mis moasiers name oui knows hes srom 1-resno ma snows events Seen Bill preparing Super Cyclone-powered MK 1 umlpper Model features silkspan covering full paint job propeller pitched up slightly 10 1 0 above established pitch center section should pitched down slightly station prop actually correct 75% station pitch measured other stations little above little below geometric pitch net effect slightly increase average pitch prop manufacturer must experiment pitch distribution stick props designs will know prop will perform Efficiency constantly changing rpm Model props turn such high rpm have efficiencies 40% 50% am still confused two components prop thrust think thrust generated both upper face prop approximately what percentage thrust con tributed eachand what speeds want thank time effort put column reply Dont know what want letter Ive got good idea would appreciate comments would care make comments column will short due lack space next month Ill talk about percentage thrust generated two sides prop Basically agree everything Bill Cassidy alleged have said alluded differences way prop manufacturers made products April 1980 column As far what want complex controversial letters can see what did Others like same other subjects welcome encour aged general interest Ill see get printed Ron Van Putte 111 Sleepy Oaks Rd Fort Walton Beach FL 32548 FF Old-Timers/Haught Continued page 54 like use nearly full-strength adhering covering Acrylic lacquer thinner obtainable automotive supply house works well either nitrate butyrate dope Acrylic lacquer thinner comes three grades cleanup thinner works fine cheap does produce high gloss does soften previous coats great degree light-penetration thinner does soften some high gloss thinner has deep penetration Various brand names available have basic grades Butyrate dope may applied over nitrate dope vice versa Some builders begin finish nitrate complete epoxy paints either clear pigmented personally like keep finishes pure throughout easier patch repair basic dope finishes Initial coats dope should brushed ensure good bond Later coats may sprayed good ventilation available Brushing first coat fabric particularly silk can problem dope tends brushed through cloth runs down inside creating blisters fabric problem can virtually eliminated applying dope fo new foam brushes Just dip brush dope drag across fabric lays film dope surface will soak enough good bond creating blister effect Dont go over wet areasjust overlap slightly pass brush About five coats dope should provide serviceable finish depend ing course much dope thinned like bring up light gloss stop Less 77Dave Dlatt iviodels Inc Air cylinder 5/8 bore New design Y-LOCK provides positive lock UP asd DOWN Mt super-tough Only 1 3/8 high fits airfoilCAPRON Low profile asd overall compact size Retraction angle t5 9O --specify ordering Lz fl7 DEVELOP Massive legs--i /2 diameter alloy 1* spring shock-absorbing bottom end L included REFINE EXPAND Experience RLG System customers ourselves over past 2 years has resulted numerous mechanical revisions improvements have incorporated fanfare significant result has highly refined retract system large models io 30 lbs Besides being used own 1/5 scale kits recommended Bud Nosen P-Si P47 Vito Fomeo big Sea Fury several others versatility system has expanded several ways have choice 850 900 retraction angle choice leg-under-cylinder leg-away-from-cylin der offer free leaflet describing simple modification up-and-twist Corsair style operation another showing noseleg modification Different coils available unique oleo shock-legs handle various weights model instructions now include details tail wheel hookup Sure Piper Cubs nice youre thinking about large-scale model retract-gear ship Dave Platt RLG System has made designs possibleSystem Price $12900 Outfit Includes 2 main units shock-legs air tank switcher pressure indicator tubing etc booklet Optional extras -- pump speed reducers extra air tanks Dave Platt products available dtrectlt/ manufacturer ONLY Send check Money Order Visa MasterCard number C 0 D orders also accepted /97DlattVISA j6951 Northwest 15th Avenue oaveEvuodels Fort Lauderdale Florida 33309 call 305/587-4861 evenings AIRO Meets SAM RC Antique & Old Timer events School Yard trainer mu —VVviijDELIts size weight make secellent chotne ton mire parts formed shape II Contains complete hardware package including miniB 8~yv R D G IiI E adisotable puohrod connectors screws blind nets Balsa wheel kit 4 wheel halves plastrc bearings washers wheel retainers pro-fabrication material selection otthe Mike surpasses Tyro Playboy Senior sPEcIFIcATIONS mnt5vanaO5 OveAii Lengthn mint chora70 Mn Sen wgt75 inns Aea sq Snorne sun -os PLAYBOY SENIOR Still Available $49 95 plus 3 00 freight tr handling Price S2895 Hobby Dealer ordering direcn please add $250 freight handling & insurance California residents add 6% Salon Tax Manufactured Tyro Models Designed no Flyll 1930 EDGEWOOD DR. PO BOX 11511 PALO ALTO CA 94306 415 856-7781 uary 1981 109 SCALE WHE RADIO CONTROL ROL-UNE 0 _ 0 0 VINTAGESMOOTHGOLDEN AGENEW sizes2YzCONTOURsizes21/iBALLOON 343/"23/43431/a 1334134132/z41/2 11443/i11/4311/443/i34514 11/251/24/z1hz53 1ls6/21451/41s61/2 ELS FREE-FLIGHT SCALE PILOTS CYUNDERS ENGINE KITS MACHINE GUN KITS PLASTIC DISPLAY MODELS EROS INTh SEND $1 FOR COMPLETE ILLUSTRATED CATALOG ___________________ DEPT MA PAWNEE ST SAN MARCOS CA 9 INTRODUCING Tile American RJL K6I R/C ENGINE RJL Industries now produces renowned engine formerly manufactured Kraft Systems Inc schnuerle ported 61 cubic inch engine provides easy starting high performance longevity Produced finest materials workmanship quality assurance youll proud have aircraft powered K61 FEATURES INCLUDE Schnuerle Ports Boost Port Double Ball Bearings Forged Alloy Piston & Con Rod Bushed Connecting Rod 0- ring Sealed Back Cover 16 HP 15500 RPM SUGGESTED RETAIL $13995 Muffler Included Send Free Catalog Today R J L INDUSTRIES P0 Box 5654 Pasadena CA 91107 1831 Business Center Dr Duarte CA 91010 allows oil soaking begins invite warps Incidentally have just learned R 1 Mikkelson producing nitrate dope red yellow blue orange black white distil bution Old Timer Models PO Box 913 Westminster CA 92683 last word Dont stink up house just before company comes may understand reference dope Clarence Haught Rt 5 Box 16 CouerdAlene ID 83814 i 213/359-0016 RC Helicopters/Chesney Continued page 33 sponses As someone told few years back might get trouble faster can get out trouble faster too course Heli copter will respond differently pilots capabilities will vary best rule may well fly way comes out box Thought might enjoy knowing few times snows down South photos shows mere snow cant stop dedi cated chopper pilot like W R Hartness Sanford NC Also special tip winter fliers Lloyd Wheelerwatch out rotor blade icingSee next month Dave Chesney 9 Box 621A Greensboro NC 27409 RC Soaring/Pruss Continued page 31 place fastest time around 76-kilometer 472-mi Great Race course race Pat Flinn Greater Detroit Soaring Hiking Society won last year flight 304 miles November MA challenge open AMA chartered clubs further formation may obtained sending stamped self-addressed business envelope address below Good Lift Dan Pruss RR 2 Box 49D Plainfield IL 60544 RC Scale/Wischers Continued page 35 Early morning wind light Brian Allen flew Gossamer Albatross misfortune Wittman Airport day pleasure introduction also met Brians parents source modesty equanimity became apparent Scale race-plane buffs fullsize reproductions Gee Bee Z Travelair Mystery Ship Laird Super Solution along Jimmy Doolittle flew original Laird Bendix Thompson Trophy races Two weeks after convention again Wittman field attended three days World Aerobatic Championships Forty-two men nine women 10 countries included competition about 20 planes use several pilots taking turns flying some planes Pitts 5-1 S-2s common US designs along Christen Eagle Leo Loudenslagers winning Laser 200 German team used Zlin SOL France three CAP 20s CAP 21 ASA 200 CAP 20 fuselage tapered wing place usual semi-elliptical planform aerobatic types ideal Scale projects some already available kit form CAP 20 featured construction article March 1980 issue Model Aviation United States swept first three places both mens womens divisions reader trend toward 1/5-scale practical alternative Giant Scale seems gaining foothold thought letter Louie Scribner contained material general interest Nats chance visit Springfield MAC field Donnelsville OH watched several fellows flying new Old-Timers seven-foot-span range powered 05 60 4-cycle engines impressed quiet engines low rpms floating ability planes occurred build Sport Scale might build Piper 1-3 along same lines would fly slowly smoothly calm air using same 05 60 engine might add Im interested belt drives chain-saw engines Giant Scale Ive already built Sig J-3 turned out rather nicely Im considering scaling Sig plans up 117 times 1/6-scale handle 05 60 engine seems have about power good 40 14-6 7500 rpm Obviously -scale too much 1/5-scale might right would produce following numbers Span 845-in chord 12-in wing thickness 1-5/16-in overall length 52-in area Continued page 112 110 Model Aviation 0 SAFE FLYING IS NO ACCIDENT