Tom,


Hitec provides 5/8" metal servo arm with their $100 servos. Most people use a 1.25" arm on the elevator of your 28%s. Is there any disadvantage using a short (5/8") servo arm and a short contro surface horn?

Ted Hauser

The main problem with the servo arm being so short is that it is next to impossible to get 3d control travel on your control surface. If you don't need 3d throws, then there is no problem.

In addition to that problem, the shorter the arms are the more stress is placed on the pushrod, clevises and hinges.

But the limitation on throw is probably the biggest problem.

TF

I had these little "blue" arm from hitec and I changed them because I had not enought throw for 3D. By the way, someone to my club had flutter because of these arms. The whole had loosen. You should go with big arms such as AirWild 1.25 inch. I changed them yesterday night and there is a HUGE difference.

julien

Toss the little arms. Go with the AirWild or SWB 1-1/4" arms. Get the type that have the additional base clamps if you can.

Ive been a little short on cash and I used the 1 inch plastic armes that came with the servo and the clevices that Tom put in his hardware kit They have been fine not sure how many flights that I have on the plane but 5 gal+ fuel has been burnt up as well as a lot of sky. Now im a beginner at the 3D stuff and ive maxed out the throw's Im going to get on these arms I get just a tad over 40 degrees with this setup. Dont use the ball links on the plastic armes Im told they will twist and break that would be a bad thing. Maybee next month ill get the bigger arms.

The heavy duty plastic arms will work out fine as long as you DO NOT USE BALL LINKS WITH THEM. Twisting under a ball link with a plastic arm is a fact and not a theory.