I am at the stage of homing the machine now and it works great except for the Y-Axis. You can see in the pictures which I put in this mail that the left side (looking from the front to the machine) has a problem with the flexible coupler when the machine tries to home the y-axis. It doesn't get far enough to reach the limit switch; some centimeters before the machine starts to chatter really loud and the left coupler looks really cramped compared to the right side. I have no idea how to fix this issue - maybe you can help me out. I tried out different things to solve the problem. I switched the Motors on both sides (including flexible couplers) with the same results. It's always on the left side despite heaving a different coupler or motor. It "works" when I loosen the screws from the Motor - it relaxes the Flexible Coupler so far that I can home the Y-Axis. But now I have a loose nema Motor on the left side.