I have been flying the Cox warbirds for a few years and want to build a really light weight one. So I decided to do a build on a AR6400 setup with a 2cell lipo. I will be using a retired Cox P-47 for this build. The plane in this build broke its back on its maiden flight when the motor burned out mid flight. Cox replaced it for me at no cost. Sorry to see them go out of business after all these years. They always treated me good.

I have been anxiously waiting for the AR6400 to be available for some time to be able to retrofit some of my older planes to make them lighter than ever before possible. I would think that this rx will be extremely popular for retrofitting and or updating old and new planes.

Anyway, I will show how to wire this deal up with the diode to allow the AR6400 to work with 2 cells.

Looking good so far, what's your projected AUW? I missed out on the Cox planes, they stopped making them just as I became aware of them and I didn't fancy paying the extortionate prices they seemed to instantly go up to...

Cox went under?? What a shame.

Good luck with the rest of the build, modfly.

Nick

Originally Posted by thewildweasel

Looking good so far, what's your projected AUW? I missed out on the Cox planes, they stopped making them just as I became aware of them and I didn't fancy paying the extortionate prices they seemed to instantly go up to...

I'm shooting for 3.5 oz. the stock RTF P-47 I have weighs 5.75 oz. These are good flying birds but are not all that aerobatic with the dihedral wing but if you give them enough power, they can do some Aero..this one will have landing gear and be operated of pavement...

Here is a video of my ARF Cox P-40 @ 5oz flying at the mall..

CMW P 40 (1 min 29 sec)

Modfly, all of mine are right at , or just under 4 ounces with landing gear. That is using 2, 4 gram servos, 6100 rx, t-bird 6, 10 gram outrunner and a 2s 300 lipo.
Glad I still have a closet full of these planes...
Currently have a zero, 190 and 109 flying in that configuration.

The ARF P-40 is 4 channels with a 2s 350mah lipo. I will actually weigh it as the weight I posted was an estimate. The RTF P-47 has the stock 6cell nimh battery in it and that is what makes it so heavy. It also has landing gear with steering tail wheel like the P-40.

My plan is to do the P-47 as a 3 channel with RET. then I will add ailerons later. I want the lightest possible plane to see how that works then I will fly it like that and eventually add the ailerons.

What we are doing here is running the AR6400 off the ESC BEC through a diode that drops the voltage depending on the BEC output of the ESC. This ESC BEC puts out 4.9v.


edit..I tested the voltage to the AR6400 under load through the diode and it read 4.1v. So this diode deal works good.

The next step is to switch modes on channel 3 or throttle channel. http://www.rcgroups.com/forums/showp...73&postcount=7

modfly - if it's the same 5amp esc you got from that brushless heli upgrade kit it's a very good possibility it's a 1s only speed controller. I think AEO does have a 2s 5amp, but just wanted to make sure you were aware before you power it up.

This one came from the BL Lama upgrade kit Sketch and is for a 2s lipo. I can't find the link for AEO but this one came from HC. This ESC is programmable. Not sure what the exact model is.

ok, here is the link http://aeorc.cn/english/index.php?gO...st.dwt&gcat=55


Oh, I'm using the motor to from the lama kit..so this warbird will have a heli motor.

Mounted the receiver in place with two screws so its removable. Got the linkage to the rudder and elevator done.

I have been wanting to do this install to a Cox warbird for some time. The 4g rx and twin servos is way lighter than the original radio gear setup. I estimate the original radio gear @ 40g. So this new gear is 1/10 the weight

Now for the tail wheel...

Very neat installation, I like the method of mounting the rx and I'll be using that myself - better than my usual method of a blob of hot glue which always pulls the brushless convertor off the board if I have to remove it for whatever reason. I also like the tailwheel mechanism, very simple and fuss free and as you said I can see it adding stength to the rudder at the point it's most likely to strike the ground and get damaged.

Originally Posted by thewildweasel

Very neat installation, I like the method of mounting the rx and I'll be using that myself - better than my usual method of a blob of hot glue which always pulls the brushless convertor off the board if I have to remove it for whatever reason. I also like the tailwheel mechanism, very simple and fuss free and as you said I can see it adding stength to the rudder at the point it's most likely to strike the ground and get damaged.

Thanks for the comment. I have posted this tail wheel tech many times and no one has ever said a word about it. I have been using this style tail wheel for about 4 years now on many different planes. All I need is the wheel and keeper to make one up. The rest of the parts are from scrap bits that are laying around.

Got the motor mounted. I like this motor as it sits behind the mount and is not visible from the outside keeping the stock appearance. I have this same motor in another plane and it is a very powerful motor and is perfect for planes of this size.

Nice work, Modfly! I stuck a Park 250 in a Hobbyzone FF Spitfire. Same thing as Cox, if I recall, just more work (hinging and hogging out the old power unit) to convert. It's a pretty spunky flyer. Yours ought to be a rocket. Are you planning to eventually add two aileron servos?
MR2