When running the machine back to front, I get a constant clicking sound coming from the right Y axis. I cannot localize the sound to determine which part it is coming from, though. Watching the set screw on the acme nut, it appears to happen at the same point on each revolution.
When I run the machine back, there is no clicking sound.
I captured a video of this: https://photos.app.goo.gl/Zmxnb1GeHMa94hgZ7
(using UGS Platform) I had jogged the machine to the back until I stalled the motors. Then moved it forward (i.e., Y- jog) 830 mm at 2000 mm/m. To move it back, I just did the Y+ jog.
The clicking in the Y- direction does not seem to a step loss. When I jog it back, it ends up at the starting position, tight to the back stop, without triggering a motor stall.
Note the the left rail is not fixed down in the video. I detached it from the wasteboard to eliminate a left/right alignment issue as the source of the problem. However, it makes the same sound when it is fixed down.
Also, adjusting the anti-backlash nut doesn’t seems to make a difference. In this video, I have loosened off the cap screw
Any ideas on what is going on? Even better, how to fix it?