XYZ calibration fails on 4th position of 3rd iteration
I've been working with Prusa support for more than a month now, and I've made no progress with my issue. My printer (MK2 with MMU) has the latest firmware and was working perfectly until I had a failure in the Y-axis belt. Upon re-tensioning the belt, I went back to perform an XYZ calibration, and it failed time after time after time. The failure ALWAYS occurs on the 4th position of the 3rd iteration (the final step) and throws an error that reads "XYZ calibration failed. Please consult the manual."
After working intensively with Prusa support, they suggested I replace the probe, but that also didn't fix the problem. I've taken steps suggested by others to perform a factory reset, update the firmware (which was currently already), and then perform the XYZ calibration, and still it fails on the last iteration. I've already ensured I have exactly 100 mm from the back of the Z frame to the Y corner feet, and again, nothing else changed about the setup apart from re-tensioning the Y-axis belt.
I'm currently awaiting my upgrade to (almost) the MK3, so perhaps after tearing the printer apart through that effort will bring it back online (wishful thinking).
Any advice? I'm desperate here, having been down for 1.5 months with a backlog of projects to complete.
Re: XYZ calibration fails on 4th position of 3rd iteration
I had this exact same issue a week ago, what I would recommend is turning on the printer on going auto home and seeing if the pinda probe is in the correct position. If not then adjust yoir axis.
If it is in position then use a ruler to see if the distance between thr top of the frame and the bed is the same is equal all along the x axis. Mine was a combination of these two issues. I hope ive helped
Regards, Matthew
Re: XYZ calibration fails on 4th position of 3rd iteration
Thanks, Matthew. The PINDA homes just fine and all measurements from the top of the bed to the bottom of the Z frame (under the Prusa engraving) are right at 258 mm, regardless of where I measure on the bed (across all X and Y coordinates). I'm in agreement with you that this still appears to be an out-of-square or alignment issue, but this was a pre-assembled unit and my measurements check out according to the guide ( http://manual.prusa3d.com/Guide/2.+Y-axis+assembly/298?lang=en ).
I can confirm that the distance from foot to Z frame is exactly 99.55 mm on both sides. At this location, the PINDA probe doesn't exactly hit center of the first circle when homing, but getting the probe exactly centered requires a foot-to-frame distance of approximately 96.5 mm and that throws a "can't reach front calibration points" error.
Am I missing a Prusa resource where they specify exactly what all the alignment measurements should be? I've been through the manual, but can anyone point me to a better/different resource for exact measurements and strategies for aligning/squaring the frame? Is it possible that the position of the Y axis belt in the holder can cause hindrance in movement of the Y-axis?
Re: XYZ calibration fails on 4th position of 3rd iteration
Okay, this makes no sense to me, but it worked, so I'm going with it. The original issue I had was with the Y-axis belt loosening, and that was because the reinforcing wires had broken in one spot. I originally just re-tensioned the belt, but when nothing else worked, I replaced the belt altogether. Once done, the XYZ calibration worked just fine and I'm back in business. So strange, but I'm glad to have my printer back!