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.
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.
Hi I have the exact same issue from the first time I powered it on. By the way I can’t really understand how to fix, could you please provide me a more detailed fixing process. Also does it opening the linear module voids the warranty? Sorry but It’s my first 3D printer and I’m not really familiar with it (before reading this thread I was thinking that’s normal even if it is a really loud and weird noise), I just received it less then a week ago.
I wrote a mail to service support and they kindly answered me with a step-by-step guide on how to inspect the linear module. Doing what they said I’ve found a rectangular magnet (like the ones embedded in the enclosure frame) that were obstructing the end run on the axis blocking the motor to reach the end rail switch and also generating that loud and weird noise. Now I removed it and all seems fine but I’m waiting from a confirmation from the support to know if that peace was out of place and sold go in another way inside the module or it’s just an assembly line fault.
I had this problem as well, this morning. I is now gone after pulling and pushing the tray, somehow. But: Not, when it comes to rappid movement of the tray, the lining is all the way out of wack. It is printing somewhere completely different, so I can get rid of the whole print and - maybe - start over.
Really annoying as it really seems there is something in the Y-axis either not connected (screw would be NOT NICE at this will happen again and again) or maybe already broken.
First of all: Was this it? Did the problem come back? Second: Where do I find that “magnet”? I guess, I have to remove the y-axis entirely and then, I open up the black plastic side from where the cable comes out? Could you be so kind and be a little bit more specific on this as others have the same issue. And if you could solve it, please let us know, how.
Yes and it never came back, I suggest you to open a support ticket. By the way it seems to always be something on the rail avoiding the bracket to reach the end and trigger the sensor that stops the motor. In my case was an assembly chain fault and that magnet shouldn’t be in the module at all, but in the older posts the screw found obstructing the rail was actually a part of the module that came off! Regarding the teardown process it was really easy, just about 6 screws and the plastic cap came off (the one without the cable!).
