Quote Originally Posted by Boyan Silyavski View Post
Or it could be the stepper/ servo drive is not connected properly to board. STEP signal could be Rising edge or ??? Lowering edge / what was the exact name?/ edge, which if not right, each movement you will loose 1 step. Which if running large toolpaths you could not even see it, but run short multiple tool paths and all goes out of place. BUt as others said make sure its not the pulley slipping
The way I read it, is that he is using 1 stepper with a belt connecting 4 screws and the screws are going out of sync.

I think he is using the 4 screws to just lower or higher his bed. (one at each corner)

If that is the case the rising edge thing is nothing to do with it.