RADIO CONTROL PYLON RACING liii pi rx cF1 ILt~ i7 ri awi lii k1] $50 Propeller $3 Piece Wood So want go fast Insanely fast Quarter 40 propeller prop makes difference between related different flight regimes Theres chatter Internet lately wwwrcairplanescom about high price premadeand some cases pre-test-flownwooden props Quarter 40 Some people advocating rules change allow carbon-fiber propellers belief once have good prop youre less likely break landing can rule eternity notion little pastramislicers whirling around 25000 rpm makes skin crawl theres no need worry about can rule wood dont have spend fortune doing Before start slightly uncertain about propeller works read Rick Allisons Radio Control Aerobatics column January 1999 Model Aviation Advanced students Internet access healthy tolerance charts graphs can check Martin Hepperles site [http//beadecleabsdlrde/Airfoils propdeshtm] theory Making world-beater prop requires five simple steps selecting blank checking pitch adjusting airfoil cutting length balancing finished prop Selecting blank consists buying commercially available prop closely matches ideal pitch blade area progression steps carving own wood propeller commercially available prop Text contains details inexpensive project saves time can make good prop table leg start Rev-Up 8/4 x 7/2 anything close youll generate less sawdust get better results less work cant find Rev-Ups go Zingers have true pitch quite good wood thicker wider blades Wide good Thick means sanding 8/2 x 7 best 8 x 7 next best Zingers tend have same higher pitch marked blades Much has said about importance good woodstraight grain uniform color etcand information comes people want sell bag props choose Theres no point intentionally selecting bad piece wood lessthan-perfect props can go very fast know because airplane seems sense Ive got perfect piece wood front Im final approach manages zero gopher hole field So have race second-raters usually last through contest incident Checking Pitch Use Terry Prather Edmunds Engineering 4592 Beech Rd Temple Hills MD 20748 Tel [301] 423-1825 Fax [301] 7022 136 pitch gauge Edmunds modern seems rugged Measure pitch stations 3 5 7 8 4 6 8 9 centimeters out hub respectively important measurement station 7 since thats area blade will work other stations tell much progressive pitch gain pitch prop has Less think Zingers have too much Ive lost occasion cant complain Cut diameter 71/2 inches pair side cutters ream out shaft hole fit engine Make easy slip-fit shaftnot tight Deburr hole mount prop pitch gauge pitch has same both sides pitch blade seems off about same amount stations sand back hub carefully flat sanding block #320 sandpaper things out doesnt take much Get pitch blades within 01-inch can read gauge closelya strong light over shoulder good eye essential pitch station 7 should between 7 8 inches airplanes like about 73 -inch pitch 107 Model Aviation May1999 107 33/4 FOR 71/2 DIA translates nominal 5 mph straightaway speed assuming engine can turn airplane doesnt bog down corners Adjusting Airfoil hard part behind now Ill focus top blade its curved top wing goal turn blade nice high-speed airfoilmore tip speed will approach Mach 1 less inboard need thickness efficiency strength torsional rigidity started Zinger need remove bunch wood sharpen leading trailing edges Dragon Skin Steel Sanding Sheet Red Devil mounted Red Devil holder #3329 cuts fast Stay away hub tool dont accidentally cut notch will weaken prop Work carefully until youve made diamond airfoil actually triangular cross-section since bottom flat high point 1/41/3 way back leading edge will look too thick tip will fixed Finish #120 aluminum oxide paper padded block remove gouges caused Dragon Skin Make rear part airfoil flat smooth clean can down sharp trailing edge have built Free Flight hand-launched gliders will have advantage Flatten top diamond airfoil starting about station 4 going out Use flat padded sanding block #120 paper again station 4 wont remove much material tip youll sand away airfoil until its virtually flat plate points between will bewell somewhere between Finally blend contours looks like prop again Some people like measure thickness various points calipers never have time wood anywhere near uniform density youll sand off enough balancing process thickness will about equal both sides anyway Cutting Length might wonder prop made 7/2 inches long need Quarter 40 7to 73/s-inch diameter answer lies feet sawdust inadvertently trimmed off edges tips making nice sharp Also time its done wont enough blade area station 8 measure pitch Carefully cut ends approximately 73/s inches diameter keep equal Test flex blades make sure theyre still strong enough handle three horsepower Holding #320-#400 CarborundumTM paper hand lightly go over leading trailing edges get rid splinters Youll lose little blade area dont worry engine cant turn anyway Also blunt leading edge gentle radius Sharp trailing edges speed up sharp leading edges slow down Use padded block #320 rake radius leading edge tip Keep shape blades equal can Try keep rear part tip pointy expensive props Think money youve just saved Balance Finish Its time moment truth chuck propeller balancer see turned out youre sure no witnesses use padded block #120 sandpaper thin down meaty part airfoil heavy blade until its about right Smooth out again #320 take out test run sure bring gear ear plugs safety goggles etc hit 24000 rpm first try have ajob Youll probably 22000-23000 range means need reduce diameter 71 72 inches possibly narrow tips lose some area Rebalancing isnt necessary until get home unless really hack away Funny noises runs bad fly feel lucky final touch recheck blades balance polish over #600 paper seal outside something waterproof Wax furniture polish okay clear epoxy such Z-Poxy time-consuming requires rebalancing gives very nice results best Ive found thin CyA cyanoacrylate applied quickly small wad toilet paper polished immediately back side #600 CarborundumTM paper After CyA soaks cures thoroughly polish front side #600 apply light coat wax Rubbing piece waxed paper will dont get carried away lest snap end off Ive Once youve collected half-dozen propellers run 23800-24800 rpm find ended up too small say 25500 use reference prop Run propellers same day mark flying props according far down rpm reference prop Bring out reference prop first run race day goes 26000 select flying prop marked minus 1500 get magic 24500 rpm air bad engine gets sick wont turn flying props ace hole run reference prop until resolve situation Proper storage important Keep props accessible safe mishaps best system bring out race day electric starter other pit gear piled other stuff old cardboard box clearly labeled junk props n Bearing Wow 50005500e000 Ball Bearing Glow 650070007500 Ball Bearing Diesel 650070007500 engines include silencer Add $500 P&H per Order Visa & M/C OK 7ieeW4 eatr e ad Saa Calson Engine Imports 814 S Marconi Ave Phoenix AZ USA 65022- Ph/Fax 602-863-1684 Antiques Military Civilian Helicopters Sailpianes have worlds largest aircraft documentation collection 7400 different full color photo studies 1903-1998 35000 3-view line drawings Catalog/Guide 228 pages OMGonads Mesco $1000 flyEu ape$1500 Beb Renkas 1Ass a&Aus AIRCRAFT DOCUMENTATION 3114 Yukon Avenue a Mesa CA 92626 714 979-8058 108 Model Aviation h-MP JET 061 A/C U/C& A/C
Edition: Model Aviation - 1999/05
Page Numbers: 107, 108
Edition: Model Aviation - 1999/05
Page Numbers: 107, 108
RADIO CONTROL PYLON RACING liii pi rx cF1 ILt~ i7 ri awi lii k1] $50 Propeller $3 Piece Wood So want go fast Insanely fast Quarter 40 propeller prop makes difference between related different flight regimes Theres chatter Internet lately wwwrcairplanescom about high price premadeand some cases pre-test-flownwooden props Quarter 40 Some people advocating rules change allow carbon-fiber propellers belief once have good prop youre less likely break landing can rule eternity notion little pastramislicers whirling around 25000 rpm makes skin crawl theres no need worry about can rule wood dont have spend fortune doing Before start slightly uncertain about propeller works read Rick Allisons Radio Control Aerobatics column January 1999 Model Aviation Advanced students Internet access healthy tolerance charts graphs can check Martin Hepperles site [http//beadecleabsdlrde/Airfoils propdeshtm] theory Making world-beater prop requires five simple steps selecting blank checking pitch adjusting airfoil cutting length balancing finished prop Selecting blank consists buying commercially available prop closely matches ideal pitch blade area progression steps carving own wood propeller commercially available prop Text contains details inexpensive project saves time can make good prop table leg start Rev-Up 8/4 x 7/2 anything close youll generate less sawdust get better results less work cant find Rev-Ups go Zingers have true pitch quite good wood thicker wider blades Wide good Thick means sanding 8/2 x 7 best 8 x 7 next best Zingers tend have same higher pitch marked blades Much has said about importance good woodstraight grain uniform color etcand information comes people want sell bag props choose Theres no point intentionally selecting bad piece wood lessthan-perfect props can go very fast know because airplane seems sense Ive got perfect piece wood front Im final approach manages zero gopher hole field So have race second-raters usually last through contest incident Checking Pitch Use Terry Prather Edmunds Engineering 4592 Beech Rd Temple Hills MD 20748 Tel [301] 423-1825 Fax [301] 7022 136 pitch gauge Edmunds modern seems rugged Measure pitch stations 3 5 7 8 4 6 8 9 centimeters out hub respectively important measurement station 7 since thats area blade will work other stations tell much progressive pitch gain pitch prop has Less think Zingers have too much Ive lost occasion cant complain Cut diameter 71/2 inches pair side cutters ream out shaft hole fit engine Make easy slip-fit shaftnot tight Deburr hole mount prop pitch gauge pitch has same both sides pitch blade seems off about same amount stations sand back hub carefully flat sanding block #320 sandpaper things out doesnt take much Get pitch blades within 01-inch can read gauge closelya strong light over shoulder good eye essential pitch station 7 should between 7 8 inches airplanes like about 73 -inch pitch 107 Model Aviation May1999 107 33/4 FOR 71/2 DIA translates nominal 5 mph straightaway speed assuming engine can turn airplane doesnt bog down corners Adjusting Airfoil hard part behind now Ill focus top blade its curved top wing goal turn blade nice high-speed airfoilmore tip speed will approach Mach 1 less inboard need thickness efficiency strength torsional rigidity started Zinger need remove bunch wood sharpen leading trailing edges Dragon Skin Steel Sanding Sheet Red Devil mounted Red Devil holder #3329 cuts fast Stay away hub tool dont accidentally cut notch will weaken prop Work carefully until youve made diamond airfoil actually triangular cross-section since bottom flat high point 1/41/3 way back leading edge will look too thick tip will fixed Finish #120 aluminum oxide paper padded block remove gouges caused Dragon Skin Make rear part airfoil flat smooth clean can down sharp trailing edge have built Free Flight hand-launched gliders will have advantage Flatten top diamond airfoil starting about station 4 going out Use flat padded sanding block #120 paper again station 4 wont remove much material tip youll sand away airfoil until its virtually flat plate points between will bewell somewhere between Finally blend contours looks like prop again Some people like measure thickness various points calipers never have time wood anywhere near uniform density youll sand off enough balancing process thickness will about equal both sides anyway Cutting Length might wonder prop made 7/2 inches long need Quarter 40 7to 73/s-inch diameter answer lies feet sawdust inadvertently trimmed off edges tips making nice sharp Also time its done wont enough blade area station 8 measure pitch Carefully cut ends approximately 73/s inches diameter keep equal Test flex blades make sure theyre still strong enough handle three horsepower Holding #320-#400 CarborundumTM paper hand lightly go over leading trailing edges get rid splinters Youll lose little blade area dont worry engine cant turn anyway Also blunt leading edge gentle radius Sharp trailing edges speed up sharp leading edges slow down Use padded block #320 rake radius leading edge tip Keep shape blades equal can Try keep rear part tip pointy expensive props Think money youve just saved Balance Finish Its time moment truth chuck propeller balancer see turned out youre sure no witnesses use padded block #120 sandpaper thin down meaty part airfoil heavy blade until its about right Smooth out again #320 take out test run sure bring gear ear plugs safety goggles etc hit 24000 rpm first try have ajob Youll probably 22000-23000 range means need reduce diameter 71 72 inches possibly narrow tips lose some area Rebalancing isnt necessary until get home unless really hack away Funny noises runs bad fly feel lucky final touch recheck blades balance polish over #600 paper seal outside something waterproof Wax furniture polish okay clear epoxy such Z-Poxy time-consuming requires rebalancing gives very nice results best Ive found thin CyA cyanoacrylate applied quickly small wad toilet paper polished immediately back side #600 CarborundumTM paper After CyA soaks cures thoroughly polish front side #600 apply light coat wax Rubbing piece waxed paper will dont get carried away lest snap end off Ive Once youve collected half-dozen propellers run 23800-24800 rpm find ended up too small say 25500 use reference prop Run propellers same day mark flying props according far down rpm reference prop Bring out reference prop first run race day goes 26000 select flying prop marked minus 1500 get magic 24500 rpm air bad engine gets sick wont turn flying props ace hole run reference prop until resolve situation Proper storage important Keep props accessible safe mishaps best system bring out race day electric starter other pit gear piled other stuff old cardboard box clearly labeled junk props n Bearing Wow 50005500e000 Ball Bearing Glow 650070007500 Ball Bearing Diesel 650070007500 engines include silencer Add $500 P&H per Order Visa & M/C OK 7ieeW4 eatr e ad Saa Calson Engine Imports 814 S Marconi Ave Phoenix AZ USA 65022- Ph/Fax 602-863-1684 Antiques Military Civilian Helicopters Sailpianes have worlds largest aircraft documentation collection 7400 different full color photo studies 1903-1998 35000 3-view line drawings Catalog/Guide 228 pages OMGonads Mesco $1000 flyEu ape$1500 Beb Renkas 1Ass a&Aus AIRCRAFT DOCUMENTATION 3114 Yukon Avenue a Mesa CA 92626 714 979-8058 108 Model Aviation h-MP JET 061 A/C U/C& A/C
