Left Bob Ytuarte displays Stern concentration launches Frank Garzons C ship meet Flushing Meadow Park NV Bill Boss pic Engines performance props fuel start Well said would dis cuss high performance production 40s fuel props goes three production 40s opinion lend themselves well mula4O Speed K&B 65cc ABC 40 Supertigre X-40 OPS 40 three engines have two things com monthey rear exhaust have ABC piston cylinder assem blies other high performance production 40s available rea son another think would well choose engine above three Formula 40 rules allow us run con stant diameter type exhaust extension commonly referred -wave length mini-pipe three chosen engines sport rear exhaust crankcase cast ings designed run mintpipe full tuned pipe need re member mini-pipe can longer 5 measured end pipe centerline engine cylinder cast ing three chosen engines sport ABC piston cylinder assemblies important no other reason wear abuse standpoint dont think high silicone aluminum alloy piston running chromed brass liner faster cast-iron piston steel liner aluminum piston ring cast-iron steel liner know sure wear characteristics sili cone running chrome much better experience commonly used piston sleeve assem blies tells us ABC assembly will take abuse dirt heat fuel anything else have seen Sounds am sold highsilicone aluminum alloy piston chromed brass cylinder assembly doesnt speed am remember have restart racing have restart am sure negative side everything however ABC piston sleeve assembly has pluses its favor brass has coefficient expansion extremely close high-silicone alumi num alloys also has negative charac teristics working against First brass strong steel fact free machine brass has tensile strength 57000 psi yield strength 25000 psi leadloy commonly used mild steel has tensile strength 70000 psi yield strength 60000 psi naval brass has tensile strength 75000 psi yield strength 53000 psi ob viously better suited brass use strength standpoint However naval brass does machine nearly easy free machining brass ob viously production brass liners market today made free machining brass addition wide difference yield tensile strengths free machin ing brass opposed mild steel important differences noted comparing two materials differ ence modulus elasticity eg force required bend elastically modulus elasticity brass V2 mild steel con tinued page 81 September 1976 33 Speed Formula 40 Speeda Natural John Brownlee Columbus Air Force Base MO preparing Rossi 15-powered FAI ship recent Contest Photo Diane Brownlee Below part VHP Team Arlie Fridley launches home-built 65-powered D ship Memphis contest Diane Brownlee pic table use rheostat speed could controlled unique judging table cost very little make Dale Arvin crew com mended excellent effort stand off scale Mint Julep Meet handing out bouquets always tireless effort Doug Early helpers should mentioned Several clubs worked together put fine meet have never attended Munt Julep Meet have missed largest finest Try make next year address 734 N 6th St Terrace Blue Springs MO 64015 CL Speed/Bussell continued page 33 simple terms means takes ex actly e distort brass takes distort mild steel dont have compare tensile yield modulus elasticity strengths free machining brass mild steel very long before realiz ing brass nearly strong reason others should obvious brass cylinder liners should thicker ones made steel Up now production engine manufac turers have taken consideration Brass will take little no abuse would-be engine reworker can bend brass liner use force r loving crankcase casting quicker can bat eye Also careful disassembly sembly easy warp bind brass liner Sometimes very difficult de tect especially piston sleeve assembly set up tight side Most ills caused low yield strength brass Another negative factor working against ABC piston sleeve assembly least us very difficult get exact running fit looking am blowing smoke tell possible pick up 1000 2000 rpms over average ABC assem bly get exact fit runs best Because nature alloys used would turn gray waited around fits run start trying lap hone fits after better have time patience knowledge money will make mistakes mistakes cost money involved heart engine Ah once get fit want can sit back enjoy because silicone chrome start work favor will take leaner runs plug elements hotter fuel its counterparts barring major difficulties extremely lean runs extremely hot fuel piston sleeve should last entire speed sea son Brent has used ST X-15 piston sleeve assembly since early 1975 right middle 1976 still using same engine same piston sleeve still go ing fast will discuss go about fitting ABCs later Tools want try hand improving performance engine certain tools necessary Contrary popular belief dont need have machine shop full expensive tools extremely knowledgeable engines improve performance average production engine However certain amount equipment common sense necessary might well build yourself good strong running bench build buy metal running mount bench because going spend hours bending over hot loudrunning engine also need good ac curate tachometer Believe have used stroboscope sound tach reed tach light tach direct-drive tach perfer good expensive direct drive tach over rest because easy read portable important de pendable am sorry say light tachs very dependable strongly recommend seriously want improve performance equip yourself good dependable direct-drive tach ometer An electric starter must will starting restarting hot cranky engines hand starting hot cranky high performance engine can impos sible compare engines need measuring instruments depth microm eter measure head piston clearance must also important have 0to-l micrometer 0-to-6 dial vernier caliper use both what going try accomplish article recommend good 0-to-6 dial vernier caliper versatile faster patience can learn use al accurately micrometers can now record performance compare parts feeler gauge setting rotor clearance also handy use Xacto knife old blade deburring parts removing flash castings good cleaning fluid necessary light weight machine oil protect clean parts oxidation useful time time will want alter production piston cylinder fit recommend least inexperienced person done lap ping use 1200-grit carborundum and/ white Dupont #7 polishing compound Dupont fl7 water soluble reason recommend Other above mentioned cant think anything else will need degree wheel check timing can very informative equipment properly alter sleeve timing necessary will necessary able move head engine smaller increments stock gaskets suggest make several gaskets differ ent sizes shim stock play head clearance point making gaskets 200 300 time out 003 shim brass inconvenienced build ing engines Custom-built thin 003 head gaskets sleeve shims available 0putar demaOUlhIUVIOIEB rLYI NOW AVAILABLE hetsIOStruciioas build 2 ig planOBIRD Stable tue tIre jamausY buildS last loam arid balsa _____ tlyer 3 cbaIO1 Send name address 6flenqroacliecIr ormotOESES zip 51050YARD BIRD 941 SHERWOOD DR LA GRANGE PARK ILLINOIS 0ii525 September 1976 81
Edition: Model Aviation - 1976/09
Page Numbers: 33, 81
Left Bob Ytuarte displays Stern concentration launches Frank Garzons C ship meet Flushing Meadow Park NV Bill Boss pic Engines performance props fuel start Well said would dis cuss high performance production 40s fuel props goes three production 40s opinion lend themselves well mula4O Speed K&B 65cc ABC 40 Supertigre X-40 OPS 40 three engines have two things com monthey rear exhaust have ABC piston cylinder assem blies other high performance production 40s available rea son another think would well choose engine above three Formula 40 rules allow us run con stant diameter type exhaust extension commonly referred -wave length mini-pipe three chosen engines sport rear exhaust crankcase cast ings designed run mintpipe full tuned pipe need re member mini-pipe can longer 5 measured end pipe centerline engine cylinder cast ing three chosen engines sport ABC piston cylinder assemblies important no other reason wear abuse standpoint dont think high silicone aluminum alloy piston running chromed brass liner faster cast-iron piston steel liner aluminum piston ring cast-iron steel liner know sure wear characteristics sili cone running chrome much better experience commonly used piston sleeve assem blies tells us ABC assembly will take abuse dirt heat fuel anything else have seen Sounds am sold highsilicone aluminum alloy piston chromed brass cylinder assembly doesnt speed am remember have restart racing have restart am sure negative side everything however ABC piston sleeve assembly has pluses its favor brass has coefficient expansion extremely close high-silicone alumi num alloys also has negative charac teristics working against First brass strong steel fact free machine brass has tensile strength 57000 psi yield strength 25000 psi leadloy commonly used mild steel has tensile strength 70000 psi yield strength 60000 psi naval brass has tensile strength 75000 psi yield strength 53000 psi ob viously better suited brass use strength standpoint However naval brass does machine nearly easy free machining brass ob viously production brass liners market today made free machining brass addition wide difference yield tensile strengths free machin ing brass opposed mild steel important differences noted comparing two materials differ ence modulus elasticity eg force required bend elastically modulus elasticity brass V2 mild steel con tinued page 81 September 1976 33 Speed Formula 40 Speeda Natural John Brownlee Columbus Air Force Base MO preparing Rossi 15-powered FAI ship recent Contest Photo Diane Brownlee Below part VHP Team Arlie Fridley launches home-built 65-powered D ship Memphis contest Diane Brownlee pic table use rheostat speed could controlled unique judging table cost very little make Dale Arvin crew com mended excellent effort stand off scale Mint Julep Meet handing out bouquets always tireless effort Doug Early helpers should mentioned Several clubs worked together put fine meet have never attended Munt Julep Meet have missed largest finest Try make next year address 734 N 6th St Terrace Blue Springs MO 64015 CL Speed/Bussell continued page 33 simple terms means takes ex actly e distort brass takes distort mild steel dont have compare tensile yield modulus elasticity strengths free machining brass mild steel very long before realiz ing brass nearly strong reason others should obvious brass cylinder liners should thicker ones made steel Up now production engine manufac turers have taken consideration Brass will take little no abuse would-be engine reworker can bend brass liner use force r loving crankcase casting quicker can bat eye Also careful disassembly sembly easy warp bind brass liner Sometimes very difficult de tect especially piston sleeve assembly set up tight side Most ills caused low yield strength brass Another negative factor working against ABC piston sleeve assembly least us very difficult get exact running fit looking am blowing smoke tell possible pick up 1000 2000 rpms over average ABC assem bly get exact fit runs best Because nature alloys used would turn gray waited around fits run start trying lap hone fits after better have time patience knowledge money will make mistakes mistakes cost money involved heart engine Ah once get fit want can sit back enjoy because silicone chrome start work favor will take leaner runs plug elements hotter fuel its counterparts barring major difficulties extremely lean runs extremely hot fuel piston sleeve should last entire speed sea son Brent has used ST X-15 piston sleeve assembly since early 1975 right middle 1976 still using same engine same piston sleeve still go ing fast will discuss go about fitting ABCs later Tools want try hand improving performance engine certain tools necessary Contrary popular belief dont need have machine shop full expensive tools extremely knowledgeable engines improve performance average production engine However certain amount equipment common sense necessary might well build yourself good strong running bench build buy metal running mount bench because going spend hours bending over hot loudrunning engine also need good ac curate tachometer Believe have used stroboscope sound tach reed tach light tach direct-drive tach perfer good expensive direct drive tach over rest because easy read portable important de pendable am sorry say light tachs very dependable strongly recommend seriously want improve performance equip yourself good dependable direct-drive tach ometer An electric starter must will starting restarting hot cranky engines hand starting hot cranky high performance engine can impos sible compare engines need measuring instruments depth microm eter measure head piston clearance must also important have 0to-l micrometer 0-to-6 dial vernier caliper use both what going try accomplish article recommend good 0-to-6 dial vernier caliper versatile faster patience can learn use al accurately micrometers can now record performance compare parts feeler gauge setting rotor clearance also handy use Xacto knife old blade deburring parts removing flash castings good cleaning fluid necessary light weight machine oil protect clean parts oxidation useful time time will want alter production piston cylinder fit recommend least inexperienced person done lap ping use 1200-grit carborundum and/ white Dupont #7 polishing compound Dupont fl7 water soluble reason recommend Other above mentioned cant think anything else will need degree wheel check timing can very informative equipment properly alter sleeve timing necessary will necessary able move head engine smaller increments stock gaskets suggest make several gaskets differ ent sizes shim stock play head clearance point making gaskets 200 300 time out 003 shim brass inconvenienced build ing engines Custom-built thin 003 head gaskets sleeve shims available 0putar demaOUlhIUVIOIEB rLYI NOW AVAILABLE hetsIOStruciioas build 2 ig planOBIRD Stable tue tIre jamausY buildS last loam arid balsa _____ tlyer 3 cbaIO1 Send name address 6flenqroacliecIr ormotOESES zip 51050YARD BIRD 941 SHERWOOD DR LA GRANGE PARK ILLINOIS 0ii525 September 1976 81