Don Jehlik cIiLJL BENCH RUNNING ENGINES Last lets take engine run month reviewed basic procedures Ive gone out field run engines use preparing new engines run Now found Ive forgotten something Ive needed test Heres checklist items Test stand large small tank tubing props test flight duplicate flight fuels fill bulb pump plugs glasses Also good battery leads tachom eter stopwatch 3-in-I oil tools rags notebook pencil ear protectors engine practice set everything out sure its Begin making entry notebook Engine tested type fuel etc sample format shown Ex ample 1 information entered will help keep organized during running procedures B Mount engine 50 Model Aviation going ing ut engines suitable test stand essential Ear protectors safety glasses recommended rpiii UneUk ills imporiani muns Wil inenoed flying proplarger PrODS load engine gown cause overneatina p peeu u aujust true neaule valve soon aiter engine star e ideal condition initial run new engine requires turning needle valve just enough produce 4-stroke run running engine cnecea jor temperaturem head shown bearing areas lower upper crankcase mean ing excessive heat spots fully examined text test stand large tank Hook up fuel line pressure line necessary close needle valve C Put prop intend fly flipping blade 450 horizontal com pression D Fill tank E Open needle valve per instructions engine draw fuel through line prime ex haust intake hook up battery start engine familiar running en gines some tips will help a Initial runs recommended flying prop important because larger props load engine down tend magnify mechanical dimensional problems engine Remember break-in should free abnormal stresses possible b Keeping needle valve closed until ready start helps prevent acci dental flooding due fuel level tank higher needle valve siphon problems etc c Mounting prop 450 horizontal does couple things flip finger gets out way en gine fires will learn use just hand finger wrist down flip you actually turn engine over faster thereby helping engine start see engines blow piston raised top stroke leak fuel air mixture piston turned over faster engine turned less leaks consequently higher compres sion available provide effective com bustion starting d After prime engine hook up battery grab prop blade firmly turn through compression rapidly prop kicks engine fires means engine properly primed ready run turn hand until does norm ally will flip start last tip always flip using index finger prop blade between last knuckle finger tip Always flip finger close hub prop possible greatly increases speed rota tion Remember ear protection e When engine starts dis connect battery until have op portunity listen engine run adjust needle valve running smoothly its running well too rich lean battery will help keep running until can correct needle valve setting some symp toms Too rich Too much fuel engine can start slowly quit visibly throw ing fuel out exhaust run slowly unevenly throwing fuel Turn needle valve enough allow engine run evenly what called 4stroke means engine still rich fuel does combust stroke initial run new engine ideal condition Continued page 97 ENGINE TEST Engin Plug Prop Fuel 8a ________________ 8________________ ________________ b_______________ I,_______________ C _________________ C ________________ C ________________ dd _______________ d _______________ 1 Breakln Plug Prop_____________ Fuel_____________ Notes Plug___________ Prop____________ Fuel Notes Final PlugPropFuelrpm Notes Final PlugPropFuelrpm Notes Plug test notes Fuel test notes Accessories test notes Muffler Throttle Fuel Pump Operating characteristics February 1978 51 Date__________ Final rpm _________ Final rpm____ 2 45 practiced eye finds tell-tale clues engine broken down examination NEWf MUFF-L-IT SERIES Available B C engines E REGULAR IT REAR EX Six eight Ob reduction noise engines Proportional volumne expan sion chamber Large exhaust nozzle low back pressure Little no loss power No 33109IN$749 No 3022940tO35 No 3034550$549 *nubu B m 0 oh4a No304RX09it$1095 No305552944$1195 90306534550tt3n5 1/2A MUFFLER Fits COX 049 engines No 3000049$549 No 3005051$549 Sympo 78 can whip out article covering some aspect Free Flight within next month two please send abstract proposed paper Bob Dodds Box 436 Rancho Stanta Fe CA 92067 Bob Meuser 4200 Gregory St Oak land CA 94619 Bumbled Bee/Pallet continued page 58 ber years great success also pre-shrink condenser paper damp ening allowing air-dry before applying structure reduces later warping surfaces due vary ing humidity Power requirements will course vary site site depending upon ceiling height However will likely working 035 065 rubber loop lengths between 10 14 depending upon weight particular model again characteristics site Adjustments desired flight circle fly conventionally left 35- 50-ft circles partially built-in vir tue fin formed condenser paper covering between two sup port posts forward canard surface being off-set left turn because socket rear post glued right side motorstick front socket center-line Additional turn trim can accomplished using either side-thrust differential incidence twist left right canard halves some combination two Optimum flight performance requires much trial-and-error testing varying combinations power rubber cross-sec tion length number winds wing canard trim settings Two partic ular tips dont afraid experiment CG location adding very small amount ballast clay fore aft sure wind rubber-motor left otherwise youre going very embar rassed Bumbled-Bee tries fly back towards instead forward away However get going right direction pa tience methodical approach trim adjustments think youll find little Easy-B canard fun fly fully competi tive conventional designs very least its eye-catcher conversation-starter Engine Technique/Jehlik continued page 51 Too lean enough fuel engine starts gains rpm rapidly slows down dies usually 3-5 seconds prepared adjust needle valve soon after engine starts Ive provided plenty props chances chew fin gers finally learned its best think about what may have before start ing engine Safety precautions aware fuels flammable smoke around fuels careful cause sparks battery leads stand beside en gine running Prop blades thrown off high velocity like arrows wear glasses preferably safety lenses avoid splashed fuel eyes protect moving objects use ear protection model engines definitely loud enough cause permanent partial hearing losses enough exposure Think ahead plan what will develop ritual about use wood fiberglass props tests f Now new engine running smooth rich real business bench running begins What should what should know 1 First running feel engine carefully Touch crankshaft housing should feel cold times warm hot stop engine shaft will too tight housing bearings improp erly mounted etc means take en gine apart examine surfaces shaft housing bore signs rubbing galling back duPont white rubbing compound #400 wet dry pa per remove signs damage 2 Feel bottom crankcase front back Heat front means problem rear ball bearings rear rotary valve induction engine has Crankshafts pressed too tight bearings loaded bearing inner race pulled off-center will cause heat lose power fail premature ly sure shaft slides bearing easy finger push fit Heat rotary valve means valve too close backplate warped pushed crankshaft drive pin backplate process elimination can identify problem correct 3 Feel upper part crankcase hot spots case should remain cool bypass transfers located feel evenly hot around fins con trast head should feel really hot want pull hand away involun tarily 70% heat absorbed engine itself typically expressed through head upper part case apparently hot head stop en gine disassemble hold sleeve wiped dry up light carefully look bright shine gall marks means too tight portion sleeve 4 Condition piston/sleeve Lapped Steel sleeve shiny full distance above exhaust port piston/sleeve fit too tight two remedies run b lap recom mend running tight piston because places too much strain reciprocating parts takes too long arrive cor rect fit unless use Lustrox obtained Duke Fox used directed prefer lap again duPont white compound piston begins show small verti cal scratch marks look through exhaust port run until lapped out have found little marks really cut power life engine allow develop have lapped new engine seven times order February 1978 97 jtu~I MANY OTHER ACCESSORIES SEE YOUR DEALER SEND FOR CATALOG CAR BUFFS SEND FOR OUR THUNDER ROAD CATALOG U R T S S UEMhI V PLANS aLflEI U sY RALPH BECK NOW AVAILABLE FROM 170d0 ENT CORP P0 BOX 9641SAN DIEGO CALIFORNIA 92109 SEND 1O FOR COMPLETE CATALOG OF AIRCRAFT HARDWARE & ACCESSORIESPLUS DESCRIPTIVE JENNYBROCHURE prevent condition Seems like lot work pays off ABC Its really hard tell whats hap pening chrome bore visual signs lot harder see look two things First shiny spots actually just little shinier rest chrome surface hold sleeve up strong light attempt cast shadow top piston comes top stroke shadow means oversize piston has pushed chrome deformed brass substrate beneath either condition lapping indicated Ringed Piston want sleeve shiny top bottom ring travel around surface sleeve either out round warped bulged spots Look rings carefully perfectly wear pattern rings case ringed pistons round true sleeves round rings necessary maximum power must try achieve condi tion difference can easily amount nearly 1000 rpm flying prop Now some basic procedures have followed lets continue running engine Assume engine running fine problems have identified solved Run engine short 2-minute runs until will hold really full power setting dura tion run switch prop 1 pitch lower ss diam eter repeat runs rich settings full power Examine engine continu ously during run signs over heating inability hold rpm fixed setting etc purpose smaller pitch diameter props prepare engine run satisfactorily rpms will achieve air some prop will run 3000 rpm faster intend fly want finish initial break-in Assuming have used same basic fuel started now time switch potent fuels intend use start 5% nitro fuel except FAT fuel engines switch fuel intended use flying RC 12% nitro good year-around brew CL 12% stunt sport 40% second step running high-nitro engines fol lowed 65% 78% depending high nitro application Again start flight prop short runs until engine stabi lizes put lower load props until engine runs easily 3000 rpm over flight prop rpm successive fuels until reach final brew Got notebook Conclusion will achieve two really important objectives following pro cedures outlined First will acquire ability understand some intrica cies engine operate will assured have top mechani cal condition properly prepared fly Second will learn operate engine what sounds like re acts what needle valve response likes started choke prime etc means go out fly will know engine prob lems come up engine initially installed plane boat car will know source problem engine something else Bench running can developed pro vide serious modeler far formation Two examples 1 Running several engines identical make comparison performance swapping parts between engines get best engine J E Albritton Herb Stock ton ran seven Supertigre 29s session recorded 900 rpm difference between best worst engine methodically swapped parts among engines obtain best crankcase bear ings crank rod piston-sleeve set head almost went nuts taking things apart keeping track swaps Net result 700 rpm over best seven engines Analysis what best-best engine provided basis what developing still power provided recorded what did what notebook kept track important observations 2 Running engines dynamometer making power fuel consumption tests sophisticated work type sometimes produces results swap-and-try method just mentioned Ill cover sophisticated testing development procedures later articles next article will power trains engine mount tank prop accessories put model make go Don Jehlik 438 Schweer Dr Star Route 1 Hawthorne NV 89415 CL Scale/Gretz continued page 42 Super Team Ray Smith Los Alamitos California highest ranking member 1978 FAT CL Scale Team having won first both Open AMA Scale team selection program 77 Nats Riverside Ray plans add detail already outstanding Nats winning Messerschmitt BF-109E use World Championships World Cham pionships tenatively scheduled early August England Dimensionally Rays scratch-built Messerschmitt 1 1 ft scale 48 11/16 wing span Its powered OS Max 60 Top Flite 12-6 prop weight ready fly full fuel bomb load 7 pounds Rays ingenious scale building reflects technical background has building flying model airplanes 40 48 years works Laboratory Machine Shop Supervisor Aerospace Corp said main interests model ing currently understandably CL RC scale although also competes CL Combat Stunt Rat Race Car rier beauty AMAs team programs over years has team members selected purely con test performance some other countries know much can afford spend trip oversees Ray Smith other members 78 CL Scale Team first time FAT competitors earned positions open competition can help maintain ideal selec tion process buying FAT stamp $1 send 78 AMA mem bership fee money provides vital support FAT teams future perhaps direct approach Scale Team funding can pro jects National Scale Society Patch sales Nats WC movie slide pro gram rentals could considered among other things Flat Tires Did notice coverage photos airplanes entered Nats World Championships have flat meaning non-glossy tires Its true Now dont scoff mumble something about crazy museum scale builders Scale judging especially Sport Scale game realistic im pressions Glossy non-glossy tires may things first look scrutinizing scale model small secrets can add up difference between model airplane realistic illusion full-size air plane should consider trying next project may worth extra point two often differ ence between winner also rans Luckily glossy tires can easily fixed scale modeling little sand paper elbow grease Notice photo two PB Aeroscale wheels before after sandpaper treatment Sanding yields just right effectstill smooth realistically dull Sanding yields just right effectstill smooth realistic ally dull Sanding tires perfect job 98 Model Aviation
Edition: Model Aviation - 1978/02
Page Numbers: 50, 51, 97, 98
Don Jehlik cIiLJL BENCH RUNNING ENGINES Last lets take engine run month reviewed basic procedures Ive gone out field run engines use preparing new engines run Now found Ive forgotten something Ive needed test Heres checklist items Test stand large small tank tubing props test flight duplicate flight fuels fill bulb pump plugs glasses Also good battery leads tachom eter stopwatch 3-in-I oil tools rags notebook pencil ear protectors engine practice set everything out sure its Begin making entry notebook Engine tested type fuel etc sample format shown Ex ample 1 information entered will help keep organized during running procedures B Mount engine 50 Model Aviation going ing ut engines suitable test stand essential Ear protectors safety glasses recommended rpiii UneUk ills imporiani muns Wil inenoed flying proplarger PrODS load engine gown cause overneatina p peeu u aujust true neaule valve soon aiter engine star e ideal condition initial run new engine requires turning needle valve just enough produce 4-stroke run running engine cnecea jor temperaturem head shown bearing areas lower upper crankcase mean ing excessive heat spots fully examined text test stand large tank Hook up fuel line pressure line necessary close needle valve C Put prop intend fly flipping blade 450 horizontal com pression D Fill tank E Open needle valve per instructions engine draw fuel through line prime ex haust intake hook up battery start engine familiar running en gines some tips will help a Initial runs recommended flying prop important because larger props load engine down tend magnify mechanical dimensional problems engine Remember break-in should free abnormal stresses possible b Keeping needle valve closed until ready start helps prevent acci dental flooding due fuel level tank higher needle valve siphon problems etc c Mounting prop 450 horizontal does couple things flip finger gets out way en gine fires will learn use just hand finger wrist down flip you actually turn engine over faster thereby helping engine start see engines blow piston raised top stroke leak fuel air mixture piston turned over faster engine turned less leaks consequently higher compres sion available provide effective com bustion starting d After prime engine hook up battery grab prop blade firmly turn through compression rapidly prop kicks engine fires means engine properly primed ready run turn hand until does norm ally will flip start last tip always flip using index finger prop blade between last knuckle finger tip Always flip finger close hub prop possible greatly increases speed rota tion Remember ear protection e When engine starts dis connect battery until have op portunity listen engine run adjust needle valve running smoothly its running well too rich lean battery will help keep running until can correct needle valve setting some symp toms Too rich Too much fuel engine can start slowly quit visibly throw ing fuel out exhaust run slowly unevenly throwing fuel Turn needle valve enough allow engine run evenly what called 4stroke means engine still rich fuel does combust stroke initial run new engine ideal condition Continued page 97 ENGINE TEST Engin Plug Prop Fuel 8a ________________ 8________________ ________________ b_______________ I,_______________ C _________________ C ________________ C ________________ dd _______________ d _______________ 1 Breakln Plug Prop_____________ Fuel_____________ Notes Plug___________ Prop____________ Fuel Notes Final PlugPropFuelrpm Notes Final PlugPropFuelrpm Notes Plug test notes Fuel test notes Accessories test notes Muffler Throttle Fuel Pump Operating characteristics February 1978 51 Date__________ Final rpm _________ Final rpm____ 2 45 practiced eye finds tell-tale clues engine broken down examination NEWf MUFF-L-IT SERIES Available B C engines E REGULAR IT REAR EX Six eight Ob reduction noise engines Proportional volumne expan sion chamber Large exhaust nozzle low back pressure Little no loss power No 33109IN$749 No 3022940tO35 No 3034550$549 *nubu B m 0 oh4a No304RX09it$1095 No305552944$1195 90306534550tt3n5 1/2A MUFFLER Fits COX 049 engines No 3000049$549 No 3005051$549 Sympo 78 can whip out article covering some aspect Free Flight within next month two please send abstract proposed paper Bob Dodds Box 436 Rancho Stanta Fe CA 92067 Bob Meuser 4200 Gregory St Oak land CA 94619 Bumbled Bee/Pallet continued page 58 ber years great success also pre-shrink condenser paper damp ening allowing air-dry before applying structure reduces later warping surfaces due vary ing humidity Power requirements will course vary site site depending upon ceiling height However will likely working 035 065 rubber loop lengths between 10 14 depending upon weight particular model again characteristics site Adjustments desired flight circle fly conventionally left 35- 50-ft circles partially built-in vir tue fin formed condenser paper covering between two sup port posts forward canard surface being off-set left turn because socket rear post glued right side motorstick front socket center-line Additional turn trim can accomplished using either side-thrust differential incidence twist left right canard halves some combination two Optimum flight performance requires much trial-and-error testing varying combinations power rubber cross-sec tion length number winds wing canard trim settings Two partic ular tips dont afraid experiment CG location adding very small amount ballast clay fore aft sure wind rubber-motor left otherwise youre going very embar rassed Bumbled-Bee tries fly back towards instead forward away However get going right direction pa tience methodical approach trim adjustments think youll find little Easy-B canard fun fly fully competi tive conventional designs very least its eye-catcher conversation-starter Engine Technique/Jehlik continued page 51 Too lean enough fuel engine starts gains rpm rapidly slows down dies usually 3-5 seconds prepared adjust needle valve soon after engine starts Ive provided plenty props chances chew fin gers finally learned its best think about what may have before start ing engine Safety precautions aware fuels flammable smoke around fuels careful cause sparks battery leads stand beside en gine running Prop blades thrown off high velocity like arrows wear glasses preferably safety lenses avoid splashed fuel eyes protect moving objects use ear protection model engines definitely loud enough cause permanent partial hearing losses enough exposure Think ahead plan what will develop ritual about use wood fiberglass props tests f Now new engine running smooth rich real business bench running begins What should what should know 1 First running feel engine carefully Touch crankshaft housing should feel cold times warm hot stop engine shaft will too tight housing bearings improp erly mounted etc means take en gine apart examine surfaces shaft housing bore signs rubbing galling back duPont white rubbing compound #400 wet dry pa per remove signs damage 2 Feel bottom crankcase front back Heat front means problem rear ball bearings rear rotary valve induction engine has Crankshafts pressed too tight bearings loaded bearing inner race pulled off-center will cause heat lose power fail premature ly sure shaft slides bearing easy finger push fit Heat rotary valve means valve too close backplate warped pushed crankshaft drive pin backplate process elimination can identify problem correct 3 Feel upper part crankcase hot spots case should remain cool bypass transfers located feel evenly hot around fins con trast head should feel really hot want pull hand away involun tarily 70% heat absorbed engine itself typically expressed through head upper part case apparently hot head stop en gine disassemble hold sleeve wiped dry up light carefully look bright shine gall marks means too tight portion sleeve 4 Condition piston/sleeve Lapped Steel sleeve shiny full distance above exhaust port piston/sleeve fit too tight two remedies run b lap recom mend running tight piston because places too much strain reciprocating parts takes too long arrive cor rect fit unless use Lustrox obtained Duke Fox used directed prefer lap again duPont white compound piston begins show small verti cal scratch marks look through exhaust port run until lapped out have found little marks really cut power life engine allow develop have lapped new engine seven times order February 1978 97 jtu~I MANY OTHER ACCESSORIES SEE YOUR DEALER SEND FOR CATALOG CAR BUFFS SEND FOR OUR THUNDER ROAD CATALOG U R T S S UEMhI V PLANS aLflEI U sY RALPH BECK NOW AVAILABLE FROM 170d0 ENT CORP P0 BOX 9641SAN DIEGO CALIFORNIA 92109 SEND 1O FOR COMPLETE CATALOG OF AIRCRAFT HARDWARE & ACCESSORIESPLUS DESCRIPTIVE JENNYBROCHURE prevent condition Seems like lot work pays off ABC Its really hard tell whats hap pening chrome bore visual signs lot harder see look two things First shiny spots actually just little shinier rest chrome surface hold sleeve up strong light attempt cast shadow top piston comes top stroke shadow means oversize piston has pushed chrome deformed brass substrate beneath either condition lapping indicated Ringed Piston want sleeve shiny top bottom ring travel around surface sleeve either out round warped bulged spots Look rings carefully perfectly wear pattern rings case ringed pistons round true sleeves round rings necessary maximum power must try achieve condi tion difference can easily amount nearly 1000 rpm flying prop Now some basic procedures have followed lets continue running engine Assume engine running fine problems have identified solved Run engine short 2-minute runs until will hold really full power setting dura tion run switch prop 1 pitch lower ss diam eter repeat runs rich settings full power Examine engine continu ously during run signs over heating inability hold rpm fixed setting etc purpose smaller pitch diameter props prepare engine run satisfactorily rpms will achieve air some prop will run 3000 rpm faster intend fly want finish initial break-in Assuming have used same basic fuel started now time switch potent fuels intend use start 5% nitro fuel except FAT fuel engines switch fuel intended use flying RC 12% nitro good year-around brew CL 12% stunt sport 40% second step running high-nitro engines fol lowed 65% 78% depending high nitro application Again start flight prop short runs until engine stabi lizes put lower load props until engine runs easily 3000 rpm over flight prop rpm successive fuels until reach final brew Got notebook Conclusion will achieve two really important objectives following pro cedures outlined First will acquire ability understand some intrica cies engine operate will assured have top mechani cal condition properly prepared fly Second will learn operate engine what sounds like re acts what needle valve response likes started choke prime etc means go out fly will know engine prob lems come up engine initially installed plane boat car will know source problem engine something else Bench running can developed pro vide serious modeler far formation Two examples 1 Running several engines identical make comparison performance swapping parts between engines get best engine J E Albritton Herb Stock ton ran seven Supertigre 29s session recorded 900 rpm difference between best worst engine methodically swapped parts among engines obtain best crankcase bear ings crank rod piston-sleeve set head almost went nuts taking things apart keeping track swaps Net result 700 rpm over best seven engines Analysis what best-best engine provided basis what developing still power provided recorded what did what notebook kept track important observations 2 Running engines dynamometer making power fuel consumption tests sophisticated work type sometimes produces results swap-and-try method just mentioned Ill cover sophisticated testing development procedures later articles next article will power trains engine mount tank prop accessories put model make go Don Jehlik 438 Schweer Dr Star Route 1 Hawthorne NV 89415 CL Scale/Gretz continued page 42 Super Team Ray Smith Los Alamitos California highest ranking member 1978 FAT CL Scale Team having won first both Open AMA Scale team selection program 77 Nats Riverside Ray plans add detail already outstanding Nats winning Messerschmitt BF-109E use World Championships World Cham pionships tenatively scheduled early August England Dimensionally Rays scratch-built Messerschmitt 1 1 ft scale 48 11/16 wing span Its powered OS Max 60 Top Flite 12-6 prop weight ready fly full fuel bomb load 7 pounds Rays ingenious scale building reflects technical background has building flying model airplanes 40 48 years works Laboratory Machine Shop Supervisor Aerospace Corp said main interests model ing currently understandably CL RC scale although also competes CL Combat Stunt Rat Race Car rier beauty AMAs team programs over years has team members selected purely con test performance some other countries know much can afford spend trip oversees Ray Smith other members 78 CL Scale Team first time FAT competitors earned positions open competition can help maintain ideal selec tion process buying FAT stamp $1 send 78 AMA mem bership fee money provides vital support FAT teams future perhaps direct approach Scale Team funding can pro jects National Scale Society Patch sales Nats WC movie slide pro gram rentals could considered among other things Flat Tires Did notice coverage photos airplanes entered Nats World Championships have flat meaning non-glossy tires Its true Now dont scoff mumble something about crazy museum scale builders Scale judging especially Sport Scale game realistic im pressions Glossy non-glossy tires may things first look scrutinizing scale model small secrets can add up difference between model airplane realistic illusion full-size air plane should consider trying next project may worth extra point two often differ ence between winner also rans Luckily glossy tires can easily fixed scale modeling little sand paper elbow grease Notice photo two PB Aeroscale wheels before after sandpaper treatment Sanding yields just right effectstill smooth realistically dull Sanding yields just right effectstill smooth realistic ally dull Sanding tires perfect job 98 Model Aviation
Edition: Model Aviation - 1978/02
Page Numbers: 50, 51, 97, 98
Don Jehlik cIiLJL BENCH RUNNING ENGINES Last lets take engine run month reviewed basic procedures Ive gone out field run engines use preparing new engines run Now found Ive forgotten something Ive needed test Heres checklist items Test stand large small tank tubing props test flight duplicate flight fuels fill bulb pump plugs glasses Also good battery leads tachom eter stopwatch 3-in-I oil tools rags notebook pencil ear protectors engine practice set everything out sure its Begin making entry notebook Engine tested type fuel etc sample format shown Ex ample 1 information entered will help keep organized during running procedures B Mount engine 50 Model Aviation going ing ut engines suitable test stand essential Ear protectors safety glasses recommended rpiii UneUk ills imporiani muns Wil inenoed flying proplarger PrODS load engine gown cause overneatina p peeu u aujust true neaule valve soon aiter engine star e ideal condition initial run new engine requires turning needle valve just enough produce 4-stroke run running engine cnecea jor temperaturem head shown bearing areas lower upper crankcase mean ing excessive heat spots fully examined text test stand large tank Hook up fuel line pressure line necessary close needle valve C Put prop intend fly flipping blade 450 horizontal com pression D Fill tank E Open needle valve per instructions engine draw fuel through line prime ex haust intake hook up battery start engine familiar running en gines some tips will help a Initial runs recommended flying prop important because larger props load engine down tend magnify mechanical dimensional problems engine Remember break-in should free abnormal stresses possible b Keeping needle valve closed until ready start helps prevent acci dental flooding due fuel level tank higher needle valve siphon problems etc c Mounting prop 450 horizontal does couple things flip finger gets out way en gine fires will learn use just hand finger wrist down flip you actually turn engine over faster thereby helping engine start see engines blow piston raised top stroke leak fuel air mixture piston turned over faster engine turned less leaks consequently higher compres sion available provide effective com bustion starting d After prime engine hook up battery grab prop blade firmly turn through compression rapidly prop kicks engine fires means engine properly primed ready run turn hand until does norm ally will flip start last tip always flip using index finger prop blade between last knuckle finger tip Always flip finger close hub prop possible greatly increases speed rota tion Remember ear protection e When engine starts dis connect battery until have op portunity listen engine run adjust needle valve running smoothly its running well too rich lean battery will help keep running until can correct needle valve setting some symp toms Too rich Too much fuel engine can start slowly quit visibly throw ing fuel out exhaust run slowly unevenly throwing fuel Turn needle valve enough allow engine run evenly what called 4stroke means engine still rich fuel does combust stroke initial run new engine ideal condition Continued page 97 ENGINE TEST Engin Plug Prop Fuel 8a ________________ 8________________ ________________ b_______________ I,_______________ C _________________ C ________________ C ________________ dd _______________ d _______________ 1 Breakln Plug Prop_____________ Fuel_____________ Notes Plug___________ Prop____________ Fuel Notes Final PlugPropFuelrpm Notes Final PlugPropFuelrpm Notes Plug test notes Fuel test notes Accessories test notes Muffler Throttle Fuel Pump Operating characteristics February 1978 51 Date__________ Final rpm _________ Final rpm____ 2 45 practiced eye finds tell-tale clues engine broken down examination NEWf MUFF-L-IT SERIES Available B C engines E REGULAR IT REAR EX Six eight Ob reduction noise engines Proportional volumne expan sion chamber Large exhaust nozzle low back pressure Little no loss power No 33109IN$749 No 3022940tO35 No 3034550$549 *nubu B m 0 oh4a No304RX09it$1095 No305552944$1195 90306534550tt3n5 1/2A MUFFLER Fits COX 049 engines No 3000049$549 No 3005051$549 Sympo 78 can whip out article covering some aspect Free Flight within next month two please send abstract proposed paper Bob Dodds Box 436 Rancho Stanta Fe CA 92067 Bob Meuser 4200 Gregory St Oak land CA 94619 Bumbled Bee/Pallet continued page 58 ber years great success also pre-shrink condenser paper damp ening allowing air-dry before applying structure reduces later warping surfaces due vary ing humidity Power requirements will course vary site site depending upon ceiling height However will likely working 035 065 rubber loop lengths between 10 14 depending upon weight particular model again characteristics site Adjustments desired flight circle fly conventionally left 35- 50-ft circles partially built-in vir tue fin formed condenser paper covering between two sup port posts forward canard surface being off-set left turn because socket rear post glued right side motorstick front socket center-line Additional turn trim can accomplished using either side-thrust differential incidence twist left right canard halves some combination two Optimum flight performance requires much trial-and-error testing varying combinations power rubber cross-sec tion length number winds wing canard trim settings Two partic ular tips dont afraid experiment CG location adding very small amount ballast clay fore aft sure wind rubber-motor left otherwise youre going very embar rassed Bumbled-Bee tries fly back towards instead forward away However get going right direction pa tience methodical approach trim adjustments think youll find little Easy-B canard fun fly fully competi tive conventional designs very least its eye-catcher conversation-starter Engine Technique/Jehlik continued page 51 Too lean enough fuel engine starts gains rpm rapidly slows down dies usually 3-5 seconds prepared adjust needle valve soon after engine starts Ive provided plenty props chances chew fin gers finally learned its best think about what may have before start ing engine Safety precautions aware fuels flammable smoke around fuels careful cause sparks battery leads stand beside en gine running Prop blades thrown off high velocity like arrows wear glasses preferably safety lenses avoid splashed fuel eyes protect moving objects use ear protection model engines definitely loud enough cause permanent partial hearing losses enough exposure Think ahead plan what will develop ritual about use wood fiberglass props tests f Now new engine running smooth rich real business bench running begins What should what should know 1 First running feel engine carefully Touch crankshaft housing should feel cold times warm hot stop engine shaft will too tight housing bearings improp erly mounted etc means take en gine apart examine surfaces shaft housing bore signs rubbing galling back duPont white rubbing compound #400 wet dry pa per remove signs damage 2 Feel bottom crankcase front back Heat front means problem rear ball bearings rear rotary valve induction engine has Crankshafts pressed too tight bearings loaded bearing inner race pulled off-center will cause heat lose power fail premature ly sure shaft slides bearing easy finger push fit Heat rotary valve means valve too close backplate warped pushed crankshaft drive pin backplate process elimination can identify problem correct 3 Feel upper part crankcase hot spots case should remain cool bypass transfers located feel evenly hot around fins con trast head should feel really hot want pull hand away involun tarily 70% heat absorbed engine itself typically expressed through head upper part case apparently hot head stop en gine disassemble hold sleeve wiped dry up light carefully look bright shine gall marks means too tight portion sleeve 4 Condition piston/sleeve Lapped Steel sleeve shiny full distance above exhaust port piston/sleeve fit too tight two remedies run b lap recom mend running tight piston because places too much strain reciprocating parts takes too long arrive cor rect fit unless use Lustrox obtained Duke Fox used directed prefer lap again duPont white compound piston begins show small verti cal scratch marks look through exhaust port run until lapped out have found little marks really cut power life engine allow develop have lapped new engine seven times order February 1978 97 jtu~I MANY OTHER ACCESSORIES SEE YOUR DEALER SEND FOR CATALOG CAR BUFFS SEND FOR OUR THUNDER ROAD CATALOG U R T S S UEMhI V PLANS aLflEI U sY RALPH BECK NOW AVAILABLE FROM 170d0 ENT CORP P0 BOX 9641SAN DIEGO CALIFORNIA 92109 SEND 1O FOR COMPLETE CATALOG OF AIRCRAFT HARDWARE & ACCESSORIESPLUS DESCRIPTIVE JENNYBROCHURE prevent condition Seems like lot work pays off ABC Its really hard tell whats hap pening chrome bore visual signs lot harder see look two things First shiny spots actually just little shinier rest chrome surface hold sleeve up strong light attempt cast shadow top piston comes top stroke shadow means oversize piston has pushed chrome deformed brass substrate beneath either condition lapping indicated Ringed Piston want sleeve shiny top bottom ring travel around surface sleeve either out round warped bulged spots Look rings carefully perfectly wear pattern rings case ringed pistons round true sleeves round rings necessary maximum power must try achieve condi tion difference can easily amount nearly 1000 rpm flying prop Now some basic procedures have followed lets continue running engine Assume engine running fine problems have identified solved Run engine short 2-minute runs until will hold really full power setting dura tion run switch prop 1 pitch lower ss diam eter repeat runs rich settings full power Examine engine continu ously during run signs over heating inability hold rpm fixed setting etc purpose smaller pitch diameter props prepare engine run satisfactorily rpms will achieve air some prop will run 3000 rpm faster intend fly want finish initial break-in Assuming have used same basic fuel started now time switch potent fuels intend use start 5% nitro fuel except FAT fuel engines switch fuel intended use flying RC 12% nitro good year-around brew CL 12% stunt sport 40% second step running high-nitro engines fol lowed 65% 78% depending high nitro application Again start flight prop short runs until engine stabi lizes put lower load props until engine runs easily 3000 rpm over flight prop rpm successive fuels until reach final brew Got notebook Conclusion will achieve two really important objectives following pro cedures outlined First will acquire ability understand some intrica cies engine operate will assured have top mechani cal condition properly prepared fly Second will learn operate engine what sounds like re acts what needle valve response likes started choke prime etc means go out fly will know engine prob lems come up engine initially installed plane boat car will know source problem engine something else Bench running can developed pro vide serious modeler far formation Two examples 1 Running several engines identical make comparison performance swapping parts between engines get best engine J E Albritton Herb Stock ton ran seven Supertigre 29s session recorded 900 rpm difference between best worst engine methodically swapped parts among engines obtain best crankcase bear ings crank rod piston-sleeve set head almost went nuts taking things apart keeping track swaps Net result 700 rpm over best seven engines Analysis what best-best engine provided basis what developing still power provided recorded what did what notebook kept track important observations 2 Running engines dynamometer making power fuel consumption tests sophisticated work type sometimes produces results swap-and-try method just mentioned Ill cover sophisticated testing development procedures later articles next article will power trains engine mount tank prop accessories put model make go Don Jehlik 438 Schweer Dr Star Route 1 Hawthorne NV 89415 CL Scale/Gretz continued page 42 Super Team Ray Smith Los Alamitos California highest ranking member 1978 FAT CL Scale Team having won first both Open AMA Scale team selection program 77 Nats Riverside Ray plans add detail already outstanding Nats winning Messerschmitt BF-109E use World Championships World Cham pionships tenatively scheduled early August England Dimensionally Rays scratch-built Messerschmitt 1 1 ft scale 48 11/16 wing span Its powered OS Max 60 Top Flite 12-6 prop weight ready fly full fuel bomb load 7 pounds Rays ingenious scale building reflects technical background has building flying model airplanes 40 48 years works Laboratory Machine Shop Supervisor Aerospace Corp said main interests model ing currently understandably CL RC scale although also competes CL Combat Stunt Rat Race Car rier beauty AMAs team programs over years has team members selected purely con test performance some other countries know much can afford spend trip oversees Ray Smith other members 78 CL Scale Team first time FAT competitors earned positions open competition can help maintain ideal selec tion process buying FAT stamp $1 send 78 AMA mem bership fee money provides vital support FAT teams future perhaps direct approach Scale Team funding can pro jects National Scale Society Patch sales Nats WC movie slide pro gram rentals could considered among other things Flat Tires Did notice coverage photos airplanes entered Nats World Championships have flat meaning non-glossy tires Its true Now dont scoff mumble something about crazy museum scale builders Scale judging especially Sport Scale game realistic im pressions Glossy non-glossy tires may things first look scrutinizing scale model small secrets can add up difference between model airplane realistic illusion full-size air plane should consider trying next project may worth extra point two often differ ence between winner also rans Luckily glossy tires can easily fixed scale modeling little sand paper elbow grease Notice photo two PB Aeroscale wheels before after sandpaper treatment Sanding yields just right effectstill smooth realistically dull Sanding yields just right effectstill smooth realistic ally dull Sanding tires perfect job 98 Model Aviation
Edition: Model Aviation - 1978/02
Page Numbers: 50, 51, 97, 98
Don Jehlik cIiLJL BENCH RUNNING ENGINES Last lets take engine run month reviewed basic procedures Ive gone out field run engines use preparing new engines run Now found Ive forgotten something Ive needed test Heres checklist items Test stand large small tank tubing props test flight duplicate flight fuels fill bulb pump plugs glasses Also good battery leads tachom eter stopwatch 3-in-I oil tools rags notebook pencil ear protectors engine practice set everything out sure its Begin making entry notebook Engine tested type fuel etc sample format shown Ex ample 1 information entered will help keep organized during running procedures B Mount engine 50 Model Aviation going ing ut engines suitable test stand essential Ear protectors safety glasses recommended rpiii UneUk ills imporiani muns Wil inenoed flying proplarger PrODS load engine gown cause overneatina p peeu u aujust true neaule valve soon aiter engine star e ideal condition initial run new engine requires turning needle valve just enough produce 4-stroke run running engine cnecea jor temperaturem head shown bearing areas lower upper crankcase mean ing excessive heat spots fully examined text test stand large tank Hook up fuel line pressure line necessary close needle valve C Put prop intend fly flipping blade 450 horizontal com pression D Fill tank E Open needle valve per instructions engine draw fuel through line prime ex haust intake hook up battery start engine familiar running en gines some tips will help a Initial runs recommended flying prop important because larger props load engine down tend magnify mechanical dimensional problems engine Remember break-in should free abnormal stresses possible b Keeping needle valve closed until ready start helps prevent acci dental flooding due fuel level tank higher needle valve siphon problems etc c Mounting prop 450 horizontal does couple things flip finger gets out way en gine fires will learn use just hand finger wrist down flip you actually turn engine over faster thereby helping engine start see engines blow piston raised top stroke leak fuel air mixture piston turned over faster engine turned less leaks consequently higher compres sion available provide effective com bustion starting d After prime engine hook up battery grab prop blade firmly turn through compression rapidly prop kicks engine fires means engine properly primed ready run turn hand until does norm ally will flip start last tip always flip using index finger prop blade between last knuckle finger tip Always flip finger close hub prop possible greatly increases speed rota tion Remember ear protection e When engine starts dis connect battery until have op portunity listen engine run adjust needle valve running smoothly its running well too rich lean battery will help keep running until can correct needle valve setting some symp toms Too rich Too much fuel engine can start slowly quit visibly throw ing fuel out exhaust run slowly unevenly throwing fuel Turn needle valve enough allow engine run evenly what called 4stroke means engine still rich fuel does combust stroke initial run new engine ideal condition Continued page 97 ENGINE TEST Engin Plug Prop Fuel 8a ________________ 8________________ ________________ b_______________ I,_______________ C _________________ C ________________ C ________________ dd _______________ d _______________ 1 Breakln Plug Prop_____________ Fuel_____________ Notes Plug___________ Prop____________ Fuel Notes Final PlugPropFuelrpm Notes Final PlugPropFuelrpm Notes Plug test notes Fuel test notes Accessories test notes Muffler Throttle Fuel Pump Operating characteristics February 1978 51 Date__________ Final rpm _________ Final rpm____ 2 45 practiced eye finds tell-tale clues engine broken down examination NEWf MUFF-L-IT SERIES Available B C engines E REGULAR IT REAR EX Six eight Ob reduction noise engines Proportional volumne expan sion chamber Large exhaust nozzle low back pressure Little no loss power No 33109IN$749 No 3022940tO35 No 3034550$549 *nubu B m 0 oh4a No304RX09it$1095 No305552944$1195 90306534550tt3n5 1/2A MUFFLER Fits COX 049 engines No 3000049$549 No 3005051$549 Sympo 78 can whip out article covering some aspect Free Flight within next month two please send abstract proposed paper Bob Dodds Box 436 Rancho Stanta Fe CA 92067 Bob Meuser 4200 Gregory St Oak land CA 94619 Bumbled Bee/Pallet continued page 58 ber years great success also pre-shrink condenser paper damp ening allowing air-dry before applying structure reduces later warping surfaces due vary ing humidity Power requirements will course vary site site depending upon ceiling height However will likely working 035 065 rubber loop lengths between 10 14 depending upon weight particular model again characteristics site Adjustments desired flight circle fly conventionally left 35- 50-ft circles partially built-in vir tue fin formed condenser paper covering between two sup port posts forward canard surface being off-set left turn because socket rear post glued right side motorstick front socket center-line Additional turn trim can accomplished using either side-thrust differential incidence twist left right canard halves some combination two Optimum flight performance requires much trial-and-error testing varying combinations power rubber cross-sec tion length number winds wing canard trim settings Two partic ular tips dont afraid experiment CG location adding very small amount ballast clay fore aft sure wind rubber-motor left otherwise youre going very embar rassed Bumbled-Bee tries fly back towards instead forward away However get going right direction pa tience methodical approach trim adjustments think youll find little Easy-B canard fun fly fully competi tive conventional designs very least its eye-catcher conversation-starter Engine Technique/Jehlik continued page 51 Too lean enough fuel engine starts gains rpm rapidly slows down dies usually 3-5 seconds prepared adjust needle valve soon after engine starts Ive provided plenty props chances chew fin gers finally learned its best think about what may have before start ing engine Safety precautions aware fuels flammable smoke around fuels careful cause sparks battery leads stand beside en gine running Prop blades thrown off high velocity like arrows wear glasses preferably safety lenses avoid splashed fuel eyes protect moving objects use ear protection model engines definitely loud enough cause permanent partial hearing losses enough exposure Think ahead plan what will develop ritual about use wood fiberglass props tests f Now new engine running smooth rich real business bench running begins What should what should know 1 First running feel engine carefully Touch crankshaft housing should feel cold times warm hot stop engine shaft will too tight housing bearings improp erly mounted etc means take en gine apart examine surfaces shaft housing bore signs rubbing galling back duPont white rubbing compound #400 wet dry pa per remove signs damage 2 Feel bottom crankcase front back Heat front means problem rear ball bearings rear rotary valve induction engine has Crankshafts pressed too tight bearings loaded bearing inner race pulled off-center will cause heat lose power fail premature ly sure shaft slides bearing easy finger push fit Heat rotary valve means valve too close backplate warped pushed crankshaft drive pin backplate process elimination can identify problem correct 3 Feel upper part crankcase hot spots case should remain cool bypass transfers located feel evenly hot around fins con trast head should feel really hot want pull hand away involun tarily 70% heat absorbed engine itself typically expressed through head upper part case apparently hot head stop en gine disassemble hold sleeve wiped dry up light carefully look bright shine gall marks means too tight portion sleeve 4 Condition piston/sleeve Lapped Steel sleeve shiny full distance above exhaust port piston/sleeve fit too tight two remedies run b lap recom mend running tight piston because places too much strain reciprocating parts takes too long arrive cor rect fit unless use Lustrox obtained Duke Fox used directed prefer lap again duPont white compound piston begins show small verti cal scratch marks look through exhaust port run until lapped out have found little marks really cut power life engine allow develop have lapped new engine seven times order February 1978 97 jtu~I MANY OTHER ACCESSORIES SEE YOUR DEALER SEND FOR CATALOG CAR BUFFS SEND FOR OUR THUNDER ROAD CATALOG U R T S S UEMhI V PLANS aLflEI U sY RALPH BECK NOW AVAILABLE FROM 170d0 ENT CORP P0 BOX 9641SAN DIEGO CALIFORNIA 92109 SEND 1O FOR COMPLETE CATALOG OF AIRCRAFT HARDWARE & ACCESSORIESPLUS DESCRIPTIVE JENNYBROCHURE prevent condition Seems like lot work pays off ABC Its really hard tell whats hap pening chrome bore visual signs lot harder see look two things First shiny spots actually just little shinier rest chrome surface hold sleeve up strong light attempt cast shadow top piston comes top stroke shadow means oversize piston has pushed chrome deformed brass substrate beneath either condition lapping indicated Ringed Piston want sleeve shiny top bottom ring travel around surface sleeve either out round warped bulged spots Look rings carefully perfectly wear pattern rings case ringed pistons round true sleeves round rings necessary maximum power must try achieve condi tion difference can easily amount nearly 1000 rpm flying prop Now some basic procedures have followed lets continue running engine Assume engine running fine problems have identified solved Run engine short 2-minute runs until will hold really full power setting dura tion run switch prop 1 pitch lower ss diam eter repeat runs rich settings full power Examine engine continu ously during run signs over heating inability hold rpm fixed setting etc purpose smaller pitch diameter props prepare engine run satisfactorily rpms will achieve air some prop will run 3000 rpm faster intend fly want finish initial break-in Assuming have used same basic fuel started now time switch potent fuels intend use start 5% nitro fuel except FAT fuel engines switch fuel intended use flying RC 12% nitro good year-around brew CL 12% stunt sport 40% second step running high-nitro engines fol lowed 65% 78% depending high nitro application Again start flight prop short runs until engine stabi lizes put lower load props until engine runs easily 3000 rpm over flight prop rpm successive fuels until reach final brew Got notebook Conclusion will achieve two really important objectives following pro cedures outlined First will acquire ability understand some intrica cies engine operate will assured have top mechani cal condition properly prepared fly Second will learn operate engine what sounds like re acts what needle valve response likes started choke prime etc means go out fly will know engine prob lems come up engine initially installed plane boat car will know source problem engine something else Bench running can developed pro vide serious modeler far formation Two examples 1 Running several engines identical make comparison performance swapping parts between engines get best engine J E Albritton Herb Stock ton ran seven Supertigre 29s session recorded 900 rpm difference between best worst engine methodically swapped parts among engines obtain best crankcase bear ings crank rod piston-sleeve set head almost went nuts taking things apart keeping track swaps Net result 700 rpm over best seven engines Analysis what best-best engine provided basis what developing still power provided recorded what did what notebook kept track important observations 2 Running engines dynamometer making power fuel consumption tests sophisticated work type sometimes produces results swap-and-try method just mentioned Ill cover sophisticated testing development procedures later articles next article will power trains engine mount tank prop accessories put model make go Don Jehlik 438 Schweer Dr Star Route 1 Hawthorne NV 89415 CL Scale/Gretz continued page 42 Super Team Ray Smith Los Alamitos California highest ranking member 1978 FAT CL Scale Team having won first both Open AMA Scale team selection program 77 Nats Riverside Ray plans add detail already outstanding Nats winning Messerschmitt BF-109E use World Championships World Cham pionships tenatively scheduled early August England Dimensionally Rays scratch-built Messerschmitt 1 1 ft scale 48 11/16 wing span Its powered OS Max 60 Top Flite 12-6 prop weight ready fly full fuel bomb load 7 pounds Rays ingenious scale building reflects technical background has building flying model airplanes 40 48 years works Laboratory Machine Shop Supervisor Aerospace Corp said main interests model ing currently understandably CL RC scale although also competes CL Combat Stunt Rat Race Car rier beauty AMAs team programs over years has team members selected purely con test performance some other countries know much can afford spend trip oversees Ray Smith other members 78 CL Scale Team first time FAT competitors earned positions open competition can help maintain ideal selec tion process buying FAT stamp $1 send 78 AMA mem bership fee money provides vital support FAT teams future perhaps direct approach Scale Team funding can pro jects National Scale Society Patch sales Nats WC movie slide pro gram rentals could considered among other things Flat Tires Did notice coverage photos airplanes entered Nats World Championships have flat meaning non-glossy tires Its true Now dont scoff mumble something about crazy museum scale builders Scale judging especially Sport Scale game realistic im pressions Glossy non-glossy tires may things first look scrutinizing scale model small secrets can add up difference between model airplane realistic illusion full-size air plane should consider trying next project may worth extra point two often differ ence between winner also rans Luckily glossy tires can easily fixed scale modeling little sand paper elbow grease Notice photo two PB Aeroscale wheels before after sandpaper treatment Sanding yields just right effectstill smooth realistically dull Sanding yields just right effectstill smooth realistic ally dull Sanding tires perfect job 98 Model Aviation