[TowerTalk] Vacuum Variable Over Torque Protection?

[Kim Elmore]

This may not be the best place to ask, but I'll give it a shot:

I have a vacuum variable capacitor that I use for a shunt-feed 
L-network at the base of my tower. I tune it using a reversible DC 
motor with a reduction drive. It works well and I only need to adjust 
it over a range of a couple of turns, but the motor I use develops a 
lot of torque. In fact, it's enough torque that I'm pretty sure it 
would strip the threads if I ever bottomed them out.

I don't have a remote turns counter and I'd like some kind of 
protection against such a condition. Do any of you have any good 
over-torque protection methods I could try?

Kim Elmore, N5OP