THE PUSHER MAN.........2009
08-24-2009, 03:29 PM
#51
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RE: THE PUSHER MAN.........2009
ORIGINAL: combatpigg
John, depending on how you design yours, you might get good efficiency from it and have it fly the way you like. The design I came up with is too boxy in the rear for a 4 inch speed prop to get a full gulp of air. I think a future design will have the rear firewall no wider than the engine. The elevon servos will have to sit one in front of the other to make room. I don't know how much that would effect throw geometry...but having a 4 inch prop hiding behind a 2 inch wide firewall is no good.
John, depending on how you design yours, you might get good efficiency from it and have it fly the way you like. The design I came up with is too boxy in the rear for a 4 inch speed prop to get a full gulp of air. I think a future design will have the rear firewall no wider than the engine. The elevon servos will have to sit one in front of the other to make room. I don't know how much that would effect throw geometry...but having a 4 inch prop hiding behind a 2 inch wide firewall is no good.
Mine has the engine on a short pylon. Because the 3 blader is only small it doesn't have to be up too high. The plan is to have two 7g servos for the ailerons next to each other poking out of the sides of the fuselage. Progress so far is the wing, centre section and pylon. Hope to get onto the fuse tonight. I scored a Cedric from Pete's Pilots to man the conning tower :-)
09-01-2009, 09:17 AM
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RE: THE PUSHER MAN.........2009
ORIGINAL: combatpigg
Well....the very rare and collectable 4.5x4 Cox Rubber pusher prop was in today's mail, thenks to Robert [BuildLight] from Crete Neb [isn't Socrates from Crete?]. Very weird looking prop, very undercambered and twisted. I made a washer out of aluminum to fill the front side of the prop hub so it would fit a Norvel drive washer. It really is a load for this .061, the needle was very narrow, but the engine seemed OK with it. The launch was dicey and the model was slow to accelerate. After each dive the engine would unload enough to put out decent speed, but the engine was really lugging in the climbs.
Well....the very rare and collectable 4.5x4 Cox Rubber pusher prop was in today's mail, thenks to Robert [BuildLight] from Crete Neb [isn't Socrates from Crete?]. Very weird looking prop, very undercambered and twisted. I made a washer out of aluminum to fill the front side of the prop hub so it would fit a Norvel drive washer. It really is a load for this .061, the needle was very narrow, but the engine seemed OK with it. The launch was dicey and the model was slow to accelerate. After each dive the engine would unload enough to put out decent speed, but the engine was really lugging in the climbs.
MJD
09-01-2009, 10:47 AM
#53
RE: THE PUSHER MAN.........2009
MJD, I just did the same thing...I dug through a can full of junk Cox, AP and Norvel engine parts and found a 3 blade pusher and a rubber 6x2. Thanks but this rubber prop Robert sent will fix my semi-annual need to build a plane that roasts engines, and makes me go into raging, sweating fits of anger...or to try to prove that 1/2A pusher planes are great fun.
I wonder why they made these props too big for .049s? Maybe they were intended for the .09s? The Norvel .074 came to the rescue on this plane, but it went through glow plugs much quicker than usual. None of the runs were too lean, either. It was just getting too hot without the prop blast or onrushing air.
I wonder why they made these props too big for .049s? Maybe they were intended for the .09s? The Norvel .074 came to the rescue on this plane, but it went through glow plugs much quicker than usual. None of the runs were too lean, either. It was just getting too hot without the prop blast or onrushing air.
09-06-2009, 09:01 AM
#54
RE: THE PUSHER MAN.........2009
Hey Pigg,
I think I may have solved the mystery of the 4.5x4 cox pusher:
J.M
I think I may have solved the mystery of the 4.5x4 cox pusher:
n order to support ½-A control line speed and proto contest flyers Cox offered this speed pan. An extremely low weight of 23 grams was achieved by using Magnesium for the casting. This is to be compared to a 10% shorter speed pan produced in aluminum by Tatone which weighs 33 grams. The motor mounts had already been drilled and tapped for a tee Dee .049 engine. The instruction sheet strongly recommends to use a left handed crankshaft (for counter clockwise flight) to avoid that the model turns into the circle. These special crankshafts as well as matching propellers were also available from Cox in these years. These items had been developed mainly by Dale Kirn, who also developed some well known Cox models like the “Spook”, “Spitfire”, “Corsair”and the Buck Rogers “Starfighter”
09-06-2009, 09:33 AM
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RE: THE PUSHER MAN.........2009
ORIGINAL: Japanman
Hey Pigg,
I think I may have solved the mystery of the 4.5x4 cox pusher:
J.M
Hey Pigg,
I think I may have solved the mystery of the 4.5x4 cox pusher:
n order to support ½-A control line speed and proto contest flyers Cox offered this speed pan. An extremely low weight of 23 grams was achieved by using Magnesium for the casting. This is to be compared to a 10% shorter speed pan produced in aluminum by Tatone which weighs 33 grams. The motor mounts had already been drilled and tapped for a tee Dee .049 engine. The instruction sheet strongly recommends to use a left handed crankshaft (for counter clockwise flight) to avoid that the model turns into the circle. These special crankshafts as well as matching propellers were also available from Cox in these years. These items had been developed mainly by Dale Kirn, who also developed some well known Cox models like the “Spook”, “Spitfire”, “Corsair”and the Buck Rogers “Starfighter”
MJD
