Why do Servo Gears Strip/Wear Down?


Tales of a Rookie
Hey all,

Recently I have had a servo gear strip out on a project. What causes the gears to strip and how can it be prevented?

It would be a great help to me on future builds to know what design elements to put in to stop it from happening.




Winter is coming
I'm no expert on servos, but my understanding is that most use nylon gears, and the torque / external forces on them may cause those soft gears to wear/strip.

There are metal gear servos, that are stronger, and digital servos that also offer more torque and resolution than analog servos -- but servo size also matters as the gears are obviously going to vary in size depending on the whole servo size.


Gravity Tester
Make sure you do not try to move the servos when they are under excessive force. For example if you're control surface is somehow stuck, free it before trying to use the servo. Also with larger/faster planes you will want stronger servos because the the external forces on the control surfaces will be greater.


Flugzeug Liebhaber
I have stopped buying all servos except metal gear servos because the plastic gears strip so easily. Shock from the control lines or rods typically start a "rough spot" that is felt when a servo is rotated by hand.

Man handling servos, turning them by hand will do it too. I stripped a servo once carrying the plane to my car, a flight control snagged a door frame and "that was all she wrote"!

A gust lock would protect it when not flying, here is an example of a full scale elevator gust lock that is installed on the flight control:




Tales of a Rookie
Thanks for all the answers guys,

I will try to use Metal Gear in the future I think, a bit more expensive but you will probably save money in the long run. That gust lock looks like a cool idea, may have to make a few of those up with a big of ply.