I think it’s this number: 78664 Been corresponding with Zero on this motor since literally the day I got the machine.
It may not be all in one thread.
Initially I thought I’d done something wrong, then the problem seemed to resolve when I traded this motor from right side Z to X.
That went ok for a while, then I started having what looked like a slipping magnetic bed, except the displacement was always exactly along the X axis, and the bed showed no indication of ever moving.
Now I’m getting a slip of a few mm at sort of random points during a given print, or it prints ok, just seems random.
I am printing ABS in the enclosure, so the temps are elevated. I can’t say for sure if the problem tracks with temperature. Certainly the initial total fail of this motor when it was in Z was anything but elevated temp. It literally failed to work the first time I turned on the machine, before I even took the enclosure out of the packing. No amount of cable swapping or plug checking would get it to work, but when I swapped it to the X position, it worked fine, at least for a while. Then I got distracted by the filament switch problem.
As upsetting as this is at this moment, I’m willing to spend some time helping to find the root cause.
I’m the lead hardware engineer for backcountry access, and I have a few years experience in motion control with Hunter Douglas (expensive motorized window coverings)
I have some 40+ years of embedded systems design experience.
With the BCA products, it’s quite literally true that if my products don’t work, someone’s going to die.
I did offer a design review under NDA.
That said, my “spare time” is limited, and I didn’t buy this machine to spread it out on my workbench and diagnose it.
I’m trying to get projects done, and when this thing works, it’s glorious, but those moments are not common at this point.
I have prints that look something inbetween machined and molded quality, better than I’ve ever seen from a filament printer, including ones done by printing companies prototyping for BCA.
From what I see on the forums, you’ve got a significant issue with the motors. Many of the “bed leveling” problems may be one side of the Z failing intermittently.
Y rails may be failing to move the print for a while, causing these massive printhead messes. Similar with X I suppose, though in my case it either goes properly, or it misses a few steps and then works ok for a while again.
I might suggest a diagnostic mode that returns a given axis to the limit switch position say once per layer. You believe you are N steps away from the switch detect, so stepping back in that direction by N steps should result in a switch detect again (plus or minus some small slop) If you don’t detect the switch when you should, that would indicate that some steps were missed. Back at Hunter Douglas I created an automated test system for problems like this that logged the errors, and emailed me automatically when a problem was detected, taking a picture with a web camera, and giving me a history plot. Very revealing. I was able to improve their positioning accuracy significantly and shake out some very obscure faults that would occur maybe once a year in a real install by running those motors 24/7 and monitoring every move.
Anyway, I hope you can understand my frustration. Occasional periods of wonderful performance from the machine, marred by a string of problems.
Intermittent faults are always challenging.