motor y seem to get stuck and not moving smoothly

Godinel,

I would suggest you double check all the points I mentioned in my earlier post #41792 on 03/01/17.

Peter.

Yes, follow Peter's advices! My machine is ok now with UCCNC from Stepcraft (with UC 100 controller).

I had a ton of trouble with this--and found 2 different problems:

1. One of the bolts holding a roller on the gantry was slightly bent. If I loosened the bolt, it did not bind--but I could watch the roller bearing rotate weirdly on the bent screw. Stepcraft sent me replacements which resolved this issue.

2. Had problems afterwards (month later) where the belt was actually slipping off of the tension support--which I realigned with the belt now tending to hug a bit too close to the machine. Before, it was moving on the support away from the machine and would bind with the belt guard. Happened mainly with high-speed as moving in 1 direction along the Y-axis. Have not had further problems after this was fixed.