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Old Mar 26, 2012, 06:31 PM
RayRangel is offline
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United States, GA, Centerville
Joined Mar 2012
170 Posts
Paul Bradley!

To be honest the videos of your SR-7 (one of the prettiest Golden Age airplanes and personal favorite) that go me thinking of converting another one of Comet's 25" line. I have the foamie Aeronca Champ that I'm using to relearn flying--been away since '79--and I love it dearly. It has to be one of the best behaved RTFs there is. Since the Champ is a typical high wing design, I thought I'd build something a little different so I picked the Waco biplane. BTW, I have a Stevens Aeromodel DH 53 Hummingbird in progress.

The Waco has a little more wing area than the SR-7, but should be about the same weight depending, of course, on how many scale "extras" I add. If I keep the struts and LG fairing to a minimum, then I shouldn't be adding too much weight of parasitic drag. Honestly, being a old stick-n-tissue rubbber power indoor scale FF guy, I look at these little electrics as being way over powered. I'm looking for the Waco to have a scale like appearance when it flies. I'm not going to be disappointed if it won't barrel roll or do multiple consecutive loops. I doubt whether the stucture would pull the G's anyway.

I tool around the airfield on 1/4 to 1/2 throttle with the Champ so I figured that the P-51 power pack would be about right for a Waco. I haven't decided, yet, whether to build a tray like your SR-7 or not. DId you actually put the tray to use in other airplanes? The way I look at it is that the motors and gearboxes are cheap, It's the Spektrum 6400 that is expensive. So I've been considering ways to lift out the rxr by unpluging the motor and without disturbing the pushrods. Perhaps a strategically located hatch, a clip of some sort to hold the rxr in a specified spot and simple L bends in servo end of the push rods with a removeable retainer of some sort. All would have to be access and removed with needle nose pliers or some such.

Maybe I'm over engineering this whole thing. When it's all said an done, the fact is that a scratch build plane of this size with the 6400 in it probably costs less than any of the micro RTFs anyway. I probably should just build it, fly it 'till it hits a tree, then rip the guts out an bulid something else.

BTW, I happen to be in LA is week on buisness so I went by Ultimate Hobbies and picked up the rxr and motor. I also picked up the push rod repair kits for a Sukoi and a Champ (they only had one of each). These repair kits contain the carbon fiber push rods, wire ends (pre-bent) and the shrink tubing to connect them. Having those pre-bent wire ends and the shrink tubing is going to save some time and hassle.

What did you use for the push rods on the SR-7?

BTW, I've been considering the wisdom of replacing the balsa wing spars and all surface leading edges with spruce to provide a little more strength--I'm not the best at soft landings or avoiding collisions. Do you think the additional weight would be worth it?
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