Using xylotex 4 axis board along with Cnc4pc C-11 board.
The issue is currently on the z-axis, but it doesn't matter. I've switched the connector with the y-axis and it then occurs there, so the problem lies at the board, not in the motors.
The problem is that it is intermittent. I can shut down the PC and restart and it seems to clear up for a little while. Then out of the blue it starts again. Last time I broke an end mill because the Z-axis didn't raise up out of the workpiece.
When it is working, then it works very smoothly. But when it gets hosed up, the motor squeals like it's stalling. Occurs in both directions.
Just looking for places to start and maybe some things to check for.
Vogavt