Bent X ball screw?
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I couldn’t see anything in that video but realize I’m on a cell phone at the moment.
To answer your question, yes a bent ball screw can cause problems.
Generally if you are having stalling issues it is a good idea to review the axis mechanically. I’d start with completely disconnecting the ball screw and making sure the saddle moves smoothly from end to end. Since you suspect a bent ball screw I’d take that completely out of the machine to check it against a reference surface. (BE CAREFUL AND AVOID LOOSING YOUR BALLS). If need be straighten your screw. Reinstall the ball screw making sure everything lines up properly. You should be able to drive the saddle from end to end, by manually rotating the screw, without a noticeable change in effort required to turn the screw. Smoothie your desired motion. If it isn’t smooth, especially at the ends of travel your ball screw needs alignment.
So in a nut shell on a new build verify the mechanics. Do that first but don’t rule out electrical set up. Often people try to set acceleration too high. If you get faults that are totally random across the axis that might point to an electrical setup problem. This especially if the axis a free to move when the machine faults. Some might suggest looking here first but on a new build that hasn’t been carefully check during assembly I’d suggest looking for mechanical issues first.
By the way there are always other possibilities. For example you could have a bad ball in the ball nut that only catches once and a while. Problems like these can be tricky because the “catch” can sometimes go away when the steppers / servos fault. Conversely you could have a bad spot on the screw itself but that would be less random. Even your leadscrew thrust bearings can develop similar issues. The struggle between “is it mechanical or electrical” can be very frustrating at times.
Originally Posted by justicedavid65
