After speaking with the tech support at shopsabre (extremely helpful BTW) it seems that the servos are set with a current limiter to help preserve the motor. If the ball screw has a build up of saw dustwhen it goes through the Z range (or a large portion of it) the nut collects the gunk and the friction is increrased enough to trip the current limiter and shut down the servo. The first solution is to clean the ballscrew and nut by layer the grease on and runningit through the travel range, wiping the dirty grease off with each cycle. Next would be to change the current limiter settings which are set at a min. and there is some room to bump them up.
I cleaned the ball screw/nut assembly thouroughly as well as re-greased the tracks and so far have not had the head drop out on me- Big thanks to the awesome support of Shopsabre! |