How to properly secure aluminium servo horns to Towerpro servos?

Last night I finally put my Chinese bought biped together. Quite an exercise in frustration really, virtually every darn bracket had to be bend to fit. In hindsight I'd better made the brackets myself!


Anyway, the kit came with aluminium servo horns that are slightly too big for my Towerpro 996 servos. (It takes talent, I guess, to make things exactly so that the don't fit perfectly.) The result is of course that I have unacceptable play on the horn, weren't those aluminium horns suppose to be more durable and accurate than the plastic ones?

I'm not the first one here to buy these servo horns and servos, so someone out here already figured out the perfect solution. I think glue won't do the job because of the torque and eventually the warming up of the servo. And if it works, it will be hard to get the horn of if necessary. Maybe a lock washer will do the job?

So, how did you solve this problem? Or do you have any ideas?


Perhaps that kit was for
Perhaps that kit was for different servos than you used.

servo horn

I used servocity std servo hubs on yanbos mg996r’s. Nice snug screw down fit. Haven’t tried their servo horns but they should fit right. Good luck!


They mentioned

The seller said to use both the MG996R and the 995 servos. Either they put the wrong horns in the kit, or my servos have a different sized spline. Who knows?


I think I’ve solved the problem. At first I made a shim from very thin brass sheet. Works perfect, but it’s quite a bit of work and when removing the servo horn a new shim has to be made. Not good! I now use three layers of aluminium tape, a nice snug fit and keeps in place when removing the horn. In theory it should stay in place for a very long time since it can’t go anywhere, but only time will tell if I’m right or not.