U George M Aldrich L1KT1 UX315iX1 Just what advantage keeping secrets What advantage helping fellow competitor Well really try hard can get event state Speed modeling today opening lines Secrets Engine Performance article wrote 1968 Thanks Speed Times puhlisher Chris Sackett CL Speed no longer doldrums flourishing nicely Speed Times $22 year write North American Speed Society Box 82294 No Burnaby BC Canada V5C 5P7 reminded article during recent speaking tour Australia MAAA equivalent AMA invited speak about engines CL Stunt Nats Wagga Wagga NSW modelers Adelaide Perth What surprised did modelers parts great nation know Aeromodeler Annual piece copies invariably asked Since make living reworking engines others can give away methods techniques answer simple wants work engines going customer anyway help him just adds pastime As abetting competition just starting out have already gone other development column 1970s wrote about blow-down period governed way engine ran first time memory anyone put print port timing affected engine performance 4-2 break Stunt mode preparing presentation realized needed better way explain modify cylinder port timing hope sketch will make clear assist want own thing Whether use handi-grinder milling machine will residual burrs etc can score piston start cutting ports Ideally proper honing should clean up cylinder walls warned cylinder cleanup vital avoid piston damage other item need degree wheel can mounted crankshaft enables measure port timing degrees crankshaft rotation What want know total timewhich expressed degrees shaft rotationthat exhaust intake ports open 4-2 break engine has correct blow-down Removing head adding subtracting head shims gaskets order cleaning fingernailsnot open-heart surgery seem think Variation head clearance and/or head volume preferred method controlling 4-2 break engine breaks too hard entering -j 1 Kt B0 E07 E1 July1994 67 Willy Wiley first rear-exhaust 40The great Dan Lutz another hisRochette Rosie Reinarz starting Stunt casemasterpieces famous Tiger Shark withMorrill Hornet CE Bowden Kanga O&R 60 up frontKub maneuver chances adding shims will correct problem possible adjust point engine will never break ie fourcycle through maneuvers Lowering compression can also cause some power loss given venturi size engines have run fairly high compression low head clearance power controlled restricting venturi size tends result engine will break two-cycle stay thereexactly what dont want old Fox 35 McCoy 40 1960s what consider some best pure Stunt designs ever use fairly low compression ratios generous venturi openings McCoy has full 312 venturi bore 0765 square inch 125 GD needle valve body 039 square inches giving venturi opening 0765 minus 039 0375 square inches Compare old ST 46 sprinkler venturi bore 157 gives 0 194 square-inch-area one-half smaller McCoy 40 such great variation main reason nitromethane costs about $120 gallon Europe European modelers usually run engines no-nitro levels Consequently ST 46 came set up run such fuel results wide squish band low head clearance highcompression head set up get power what call cough syrup fuel Its hard see got lured such small venturi sizes longevity ST 46 exceeded Fox 35 though narrowed 46 squish band make large volume hemi-heads venturi sizes kept relatively constricted 285 venturi 0638 square inches 157 needle valve body 0448 square inches passing through 019 effective area wascommon short engine being starved fuel/air understand much head clearance good Stunt engine can tolerate look closely old Testor McCoy engine Never known accurate tolerances Ive seen examples wrist pin holes piston drilled 200 off intended position means piston baffle 200 off corresponding slot head Yet assembled piston baffle never hit head engine would run just fine long would last Ive never cared pressure fuel systems CL Stuntits just thing can go wrong Bladders crankcase pressure certainly worth trouble Speed Stunt Ive always preferred consistent runs suction tank Ive never experienced so-called Fox 36 burp have mentioned over years Fox 35s Oliver Tigers etc have run consistent 4-2 break no matter what maneuveruntil recently Last summer test-running customers engineor rather trying test run it would venturi cut same parabolic shape has use since 1968 tool first ground concentration focused needle valve generic brand used before Removing body found fuel bleed hole diameter about 025-030 opened about 055 installed engine ran suction just fine thank Little things can mean lot would remiss didnt mention impressions Australia first thoughts once-in-a-lifetime experience people never met rude unfriendly person Try anyplace else might want go Australia about same size US about 17 million residents Imagine being US about 200 years ago todays conveniences also impressed clean cities werethe streets looked cleaned broom dustpan easy inexpensive access model supplies US levels Australians incorporate intelligence talent effort Ive involved modeling modelers life good folks among elite modeler particular pleasure meet solid gentleman simply known Ivor F first made contact back 1960s have read about exploits endeavors ever since Famous talents jokes crazy capers Ivor teacher profession inside him beats heart truest modelers ever lived 1930s Ivor started fetchermitean endearing term used England Australia describe lads enlisted chase big boys models neophytes great man introduced modeling numbers thousands Im sure Seeing whole family arrive flying site uncommon Australia Mom baby blanket white dad boys girls fly wide selection both CL free flight also norm reminds childhood 100 million take calls 6 pm-10 pm prefer readers write since calls often catch honing oil dripping off elbows losing set dimensions dealing 0001 tolerances answer SASEs address 12822 Tarrytown San Antonio TX 78233 Tel 512 656-2021 group Classic designs seen Brett Silver Ryde NSW built Scottish Nats Ward photogorgeous replica Nobler author fly Australia 68 Model Aviation Ward Scottish Nats Mackey Gobbleswantz Ward photo Something differentIrelands Maurice Doyle entered Scottish Nats unique U-2 Ward photo
Edition: Model Aviation - 1994/07
Page Numbers: 67, 68
U George M Aldrich L1KT1 UX315iX1 Just what advantage keeping secrets What advantage helping fellow competitor Well really try hard can get event state Speed modeling today opening lines Secrets Engine Performance article wrote 1968 Thanks Speed Times puhlisher Chris Sackett CL Speed no longer doldrums flourishing nicely Speed Times $22 year write North American Speed Society Box 82294 No Burnaby BC Canada V5C 5P7 reminded article during recent speaking tour Australia MAAA equivalent AMA invited speak about engines CL Stunt Nats Wagga Wagga NSW modelers Adelaide Perth What surprised did modelers parts great nation know Aeromodeler Annual piece copies invariably asked Since make living reworking engines others can give away methods techniques answer simple wants work engines going customer anyway help him just adds pastime As abetting competition just starting out have already gone other development column 1970s wrote about blow-down period governed way engine ran first time memory anyone put print port timing affected engine performance 4-2 break Stunt mode preparing presentation realized needed better way explain modify cylinder port timing hope sketch will make clear assist want own thing Whether use handi-grinder milling machine will residual burrs etc can score piston start cutting ports Ideally proper honing should clean up cylinder walls warned cylinder cleanup vital avoid piston damage other item need degree wheel can mounted crankshaft enables measure port timing degrees crankshaft rotation What want know total timewhich expressed degrees shaft rotationthat exhaust intake ports open 4-2 break engine has correct blow-down Removing head adding subtracting head shims gaskets order cleaning fingernailsnot open-heart surgery seem think Variation head clearance and/or head volume preferred method controlling 4-2 break engine breaks too hard entering -j 1 Kt B0 E07 E1 July1994 67 Willy Wiley first rear-exhaust 40The great Dan Lutz another hisRochette Rosie Reinarz starting Stunt casemasterpieces famous Tiger Shark withMorrill Hornet CE Bowden Kanga O&R 60 up frontKub maneuver chances adding shims will correct problem possible adjust point engine will never break ie fourcycle through maneuvers Lowering compression can also cause some power loss given venturi size engines have run fairly high compression low head clearance power controlled restricting venturi size tends result engine will break two-cycle stay thereexactly what dont want old Fox 35 McCoy 40 1960s what consider some best pure Stunt designs ever use fairly low compression ratios generous venturi openings McCoy has full 312 venturi bore 0765 square inch 125 GD needle valve body 039 square inches giving venturi opening 0765 minus 039 0375 square inches Compare old ST 46 sprinkler venturi bore 157 gives 0 194 square-inch-area one-half smaller McCoy 40 such great variation main reason nitromethane costs about $120 gallon Europe European modelers usually run engines no-nitro levels Consequently ST 46 came set up run such fuel results wide squish band low head clearance highcompression head set up get power what call cough syrup fuel Its hard see got lured such small venturi sizes longevity ST 46 exceeded Fox 35 though narrowed 46 squish band make large volume hemi-heads venturi sizes kept relatively constricted 285 venturi 0638 square inches 157 needle valve body 0448 square inches passing through 019 effective area wascommon short engine being starved fuel/air understand much head clearance good Stunt engine can tolerate look closely old Testor McCoy engine Never known accurate tolerances Ive seen examples wrist pin holes piston drilled 200 off intended position means piston baffle 200 off corresponding slot head Yet assembled piston baffle never hit head engine would run just fine long would last Ive never cared pressure fuel systems CL Stuntits just thing can go wrong Bladders crankcase pressure certainly worth trouble Speed Stunt Ive always preferred consistent runs suction tank Ive never experienced so-called Fox 36 burp have mentioned over years Fox 35s Oliver Tigers etc have run consistent 4-2 break no matter what maneuveruntil recently Last summer test-running customers engineor rather trying test run it would venturi cut same parabolic shape has use since 1968 tool first ground concentration focused needle valve generic brand used before Removing body found fuel bleed hole diameter about 025-030 opened about 055 installed engine ran suction just fine thank Little things can mean lot would remiss didnt mention impressions Australia first thoughts once-in-a-lifetime experience people never met rude unfriendly person Try anyplace else might want go Australia about same size US about 17 million residents Imagine being US about 200 years ago todays conveniences also impressed clean cities werethe streets looked cleaned broom dustpan easy inexpensive access model supplies US levels Australians incorporate intelligence talent effort Ive involved modeling modelers life good folks among elite modeler particular pleasure meet solid gentleman simply known Ivor F first made contact back 1960s have read about exploits endeavors ever since Famous talents jokes crazy capers Ivor teacher profession inside him beats heart truest modelers ever lived 1930s Ivor started fetchermitean endearing term used England Australia describe lads enlisted chase big boys models neophytes great man introduced modeling numbers thousands Im sure Seeing whole family arrive flying site uncommon Australia Mom baby blanket white dad boys girls fly wide selection both CL free flight also norm reminds childhood 100 million take calls 6 pm-10 pm prefer readers write since calls often catch honing oil dripping off elbows losing set dimensions dealing 0001 tolerances answer SASEs address 12822 Tarrytown San Antonio TX 78233 Tel 512 656-2021 group Classic designs seen Brett Silver Ryde NSW built Scottish Nats Ward photogorgeous replica Nobler author fly Australia 68 Model Aviation Ward Scottish Nats Mackey Gobbleswantz Ward photo Something differentIrelands Maurice Doyle entered Scottish Nats unique U-2 Ward photo