How to make custom-length push rods

Jun 16, 2011 2 Comments by

Many kits are made to precise standards, and this includes the pushrods. They are perfect for the recommend servos, but when using servos that have the output arms in a different location, those included pushrods may not work as well. This happened to me, and it meant that I needed to make up my own pushrods for the elevators. I purchased some 2-56 threaded pushrod from the local hobby shop and cut it to the size needed, which was only about 3 to 4 inches long.

But I found out that threaded rod is not very rigid and tended to flex a little when the control surfaces were at full deflection. I had some copper tubing lying around that would allow the threaded rod to fit inside it. I cut some tubing so just about 1/2 inch of rod extended out of each side. I then used 2-56 nuts on each end and tightened down the tubing to the rod. This created a very rigid pushrod that was also very light and clean looking. You can save even more weight by using aluminum or carbon-fiber tubing instead of copper. Of course, I just used what was in the shop.

The nice thing about this is that you can make custom-length pushrod any time and not spend a lot of money doing it. Now I have extra 2-56 and 4-40 threaded rod along with the matching copper and aluminum tubing in my shop—just in case I need another custom-size pushrod.

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About the author

West Coast senior editor About me: I’ve been involved with RC aircraft since high school and have flown just about everything. I started my RC career with scratch-building, but now like many pilots I rely on ARFs to get me in the air. My main focus is on pylon racing, aerobats, combat and scale warbirds.

2 Responses to “How to make custom-length push rods”

  1. R.C.Gardner says:

    I have done the same thing, only I tapped the tubing.

  2. John Reid says:

    Hey R.C. Gardner,
    That would make a great Tips and Trick, send an e-mail to me (johnr@airage.com) with your address and a brief description and I will get it in the magazine. You’ll get a hat plus an Alien kit.
    So I would think you use a smaller rod in diameter than I do and then tap both ends and use a smaller threaded rod at each end. That would be easier. I would guess you could use a carbon fiber rod to do the same thing and make the whole pushrod a little lighter, although I think I would probably spread in some thin CA over the threads just to make a solid joint.
    Great tip R.C. Gardner

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