Rebuilding an rc plane

Hi. Been flying a freestyle quad and loving it. But I have an old rc airplane. It has a wingspan of just over a metre.

It has two servos which I have got working with a crossfire nano.

But it has a brushed motor (brushes are good) and a 30A switch. This is basically just on and off just past half throttle on the stick.

Is this a common way to fly rc planes? Never built one before.

I was thinking about just getting a brushed speed controller.

Also, Lipo or li-ion?

Thank you

I’d change from brushed to brushless, less hassle and depending on the size of your plane you might be able to use the same lipo batteries that you currently have.
Pictures would help in determining the best way forward with your build.

Thank you. I’m guessing it’s sort of a glider. I’ll rebuild as is and see if I like it. I can always change later. It’s just that it has nice folding props that fit nicely on its motor and the frame would need modifying for a brushless. Brushed Esc’s are only a tenner anyway. I did put a pic up in the past. I’ll try a 3s 3300 lipo as its spare.

The last time I saw a brushed motor and lipo combo, the lipo caught fire but it was spectacular as we watched the Spitfire bellowing and trailing smoke it was so to scale though.

When I few brushed I used Nicad batteries, your plane will have its CG based on that so check that carefully otherwise it will be a lawn dart at takeoff.

I may still have an old brushed glider somewhere in the loft I think…:thinking:

Good luck with your experiment…:+1:

It was in this thread mate.

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The state of that tells me that it’s more than likely that it will have the dreaded black wire or negative wire corrosion which is very prevalent in old RC gear.
If I was to rebuild that glider I’d remove all that RC gear and dismantle it all to especially the RX.
At a guess I’d say you could fly that with a 900-1100 KV motor and a light weight 2200mA lipo.
I’d move the servos to the back and lipo to the front, the rear area behind the servos was for the much heavier NiCd batteries.

Cheers man. I have spare 920kv motors and 20a esc so that may be the way to go. The first thing I did was take out the rx. It has a crossfire nano now configured with pwm out. Obviously I will be installing fpv on it!

And I do have two places for the battery. I do have a 14v nicad, but it’s really heavy. I will have to experiment with placement.

If you’re going FPV then brushed will be a pain from the brushed motor sparking and snowflakes in your video even with the best suppression capacitors on the motor, then again brushed motors may have come a long way since I last used them.

So had a look in the attic workshop and in the corner were these two forgotten projects.

This was my first FPV experiment with a fixed wing, my firs being a helicopter, as you can see I broke it and repaired it; It’s lain forgotten for some years.

This is VERY nice

The bay is asking for 3D printed all in one removable servo,RX and battery tray, have you thought about a design?

Here is my maiden fixed wing FPV flight with a Multiplex Easy Glider Pro. on 35 MHz, 2.4G on video.

No. But I am thinking now…

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let me know if you need any help…:+1:

Will do. My main concern is weight distribution. I’ll let it fester in my brain.

If you went for a lipo brushless route it will be a much lighter aircraft but it will mean having the lipo up front to restore the CG.

I’d do a dry mock-up of everything you intend to use, have your brushless motor, ESC and lipo up front then just place the servos to the back with your nano RX, fit the wing and move the battery until you get the correct CG say 1/4 cord slight nose down.

Ok. If I was to balance the plane on my finger, where would my finger be? At the wing joint? A little more forward? Or to the rear?

A ball park point would be about 1/4 - 1/3 back from the leading edge of the wing, measure the wing root from the leading edge to the trailing edge then divide by 4 to get the 1/4 mark, mark it then divide by 3 for the 1/3 mark and mark the point.
Since you don’t have a manual, it’s a bit of rule of thumb, the wing cord type will determine the best CG point, if you look at the wing root the highest point of the profile is about where you want the CG, based on a none tapered wing which yours looks to be.


I will read this when I am sober tomorrow. It’s still my holiday day.

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