I am looking for Semi flexible elevator control rods, that will not expand or contract, with temperture fluctuations. I have just ripped out a pair of Sullivan Gold-N-Rods because of this problem. They were terrible. The control rods are to be used for giant scale, and need to use 4-40 hardware. I'd appreciate your recommendations.

Thank you.

Ed

Semi flexible? I use 4-40 steel rod in tube. You can get both at Tower. The 4-40 rods are threaded on one end and come in vairous lengths up to 48". I generally solder a 4-40 metal clevis on the servo end and use the threaded end at the control surface.

Yeah, I gave up on golden rod and nyrods years ago. They only get used on throttle, choke, and ignition switches.
Edwin

Do the 4-40 steel rods that you use expand or contract, and change your trim settings ? ? ?

Thanks.

I've never noticed it. Stays in trim.
Edwin

Additional question : Would anyone here use 2-56 rods and hardware on a 28 pound aircraft ?

Thanks again

Ed

NO.. thats a pretty heavy plane so the flight loads might be a bit much for 2.56

If I understood you correctly, you are worried about metal expansion/contraction?...
You will want to worry about it when building long bridges, railway lines etc, not on short things like push rods - metal expansion over 48" is just about nothing in RC modelling. Also, bear in mind that when you are flying, the plane is cooled by the air moving through and past it. I think your problem lies elsewhere.

We fly in full scale aircraft in middle eastdesert where the temperature on the ground can be 55 deg Celsuis and up to minus 50 Deg C at 39 000 ft.

Just my 2 cents

Bundu

I use Sullivan Precision Rod Carbon Fiber #585 the are do not change lengths with temperature and are up to the challenge og giant scale.

" I think your problem lies elsewhere. " Wrong ! My problem lies with Sullivan Gold-N-Rods ! I have experienced the expansion/contraction properties of these for years. I would never again install Gold-N-Rods in any aircraft that I built, it's just that they came previously installed in a plane that I purchased at auction. Yes, I flew this plane many times with the Gold-N-Rods, and the variation in trim settings throughout the days flying is terribly annoying.

I ripped them out, and I'm now looking for replacement suggestions. I have used the Sullivan # 585, and they are fine, but my local hobby shop is out. Steel is also good, but their weight may unbalance my already balanced airplane.

Ed

True, the steel rods would shift the cg back a little, but I think that can be easily offset. As for golden rods, I've used them and discovered over the long term, mine got a little sticky in the tubes and caused recentering problems. Steel rod fixed it, and I didnt do any additional rebalancing.
Edwin