Y axis homing issue *** RESOLVED ***

I have encountered a problem with my A250 not homing correctly. The print head moves back and forward to home on the X and Z axes, but the print bed doesn’t finish homing on the Y axis. The print bed moves to the end of the Y axis and emits a loud humming sound, presumably the stepper motor trying to move it past the end stop.

I would upload a short video showing the problem, but I can’t upload attachments as a new user.

I’ve completed several prints from files generated by Luban in the past. This issue came up when I tried printing a file I generated in Cura (also, the first time I turned on the printer today). All subsequent attempts to home / calibrate the device produce the same issue.

Has anyone seen a problem like this in the past? How did you correct the problem?

*edit: changed title to reflect status of issue. Resolution information is in a comment below.

It sounds like the Y-axis isn’t triggering the limit switch. It might be out of place or perhaps it is not functioning. You could try swapping the two Y-axes and see if that fixes the issue. I would assume they both have limit switches but perhaps it only triggers off one of them.

Hi @Tone,

Thank you for the suggestion of checking the limit switch. I had the same thought. I wasn’t sure if the splitter for the Y axis would take the logical AND or OR of the signals from the limit switch.

Anyway, it turned out that the linear modules weren’t even reaching the limit switches. A small plastic bracket had come loose on one of the modules (this holds the metal strip in place that reduces dust intrustion). The retaining screw that held the bracket in place had fallen out. I replaced the screw and reassembled the device - it’s working fine again.

I’ve attached photos for reference in case anyone else encounters an issue like this. A short video showing the symptoms of the problem are also attached.