Having spend a year or so designing and working with colleagues on this 'electric' gear thing on our Stinger jet electric gear does pose a few challenges the main 'issue' which presents itself in electric gear is the management of locking up at each end of the travel.

If you drive the threaded rod to the lock position it generally requires slightly more current to do this and once locked ideally you want to be able to stop the motor instantly, in the real world this does not happen, inertia drives the thread hard into the end stop before the electronics can stop the motor (unless you have a painfully slow retract unit and most dont want that).

I know from experience that one fix was to provide a cushion at each end of the travel, usually in the form of a rubber/silicone washer, we used this method and I notice that so do Electron, I cannot speak for others. This dampens and slows the end stop 'crash' which gives time for the electronics to detect the current spike and shut the motor down (even reverse it momentarily too to get it ready for the return journey and to also remove some resistance).

I did not experiment with ACME threads, and it may well help, but key is the electronics (and a decent motor/gearbox) - I am sure as electric retracts develop all these things will be overcome.

Just thinking about the threaded rod maybe also a square rod with the threads on each corner would allow FOD to be scraped into the flat sections and not pose an issue with locking the thread up.......

marcs