Z axis calibration failed
Hi, i've just finished building my i3 MK3 kit.
Self test is passing ok, but XYZ calibration fails almost immediately. Also, Z axis test alone fails almost immediately. I have tried to move axis manually (from i3 menu "settings->move axis") and i have noticed that when moving Z axis manually, right Z carriage sometimes jams when moving up. After visual inspection i have noticed that right Z motor rod leans slightly to the frame. I have loosed screws mounting right Z motor, reseated the motor in it's bracket, and tightened all screws again, and it seems that right Z motor rod is almost ideally aligned now, and i am able to move Z axis from the i3 menu without jams. Still, Z calibration (and XYZ calibration) fails almost immediately.
Any tips on what to check next? Can it be failed Z axis motor?
Wojtek
Re: Z axis calibration failed
I've had z fail because the trap nut was tightened too much and bound up on the lead screw above a certain height.
Re: Z axis calibration failed
Hi, i have managed to correct the problem by loosening screws on both Z motor mounts, moving X axis all the way from the bottom to the top by turning motor rods manually, and re tightening all screws again. It seems that there was some misalignment between Z motor rods and this caused jams and calibration fails. Printer is working fine now.
Wojtek
Re: Z axis calibration failed
I have the same issue where Z axis calibration fails immediately when the carriage gets to the bottom. I looked at the firmware code that does the calibration to see what triggers the failure and the problem is twofold, first this is the line that checks for success:
if (st_get_position_mm(Z_AXIS) == MESH_HOME_Z_SEARCH)
Comparing floating point numbers with == is problematic, usually it's best to do something like taking the absolute value of the difference between the 2 values and check that it's less than an acceptable margin of error.
The second issue and the one most likely to be causing the failure is that the value of MESH_HOME_Z_SEARCH is set to 5 but when I connect the Arduino serial monitor during calibration I see a message that says echo:endstops hit: Z:10.99
Any ideas? (I tried the loosening screws trick to no avail).
OOPS!! MY BAD, NEVERMIND 😉 After staring at my machine for a while I finally realized that I had the hot-end mounted too low, tore it apart and fixed it (that was fun) and now calibration works great (although I still think the code could be a bit cleaner. Sorry for the noise.
Re: Z axis calibration failed
I have the same issue where Z axis calibration fails immediately when the carriage gets to the bottom. ...
Any ideas? (I tried the loosening screws trick to no avail).
When exactly is it aborting? Is it hitting the bed? Does it recognize the first magnet?
Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram
Re: Z axis calibration failed
I have the same issue where Z axis calibration fails immediately when the carriage gets to the bottom. ...
Any ideas? (I tried the loosening screws trick to no avail).
When exactly is it aborting? Is it hitting the bed? Does it recognize the first magnet?
Did you see the end of my (edited) post? I screwed up when installing the hot-end so the PINDA probe was stopping the z axis about 6mm too soon on the way down.
Re: Z axis calibration failed
No I didn't. Thanks for the heads up.
Often linked posts:
Going small with MMU2
Real Multi Material
My prints on Instagram
Re: Z axis calibration failed
So my MK3 which has been working perfectly for a couple of weeks suddenly started refusing to start a print saying it had failed to check the bed levelling. I re-ran XYZ calibration but each time it fails when trying to calibrate the z-axis. When just calibrating the z-axis it raises to the top, makes the whirring noise indicating it's at the end stops and the says calibration failed. At that point the LCD says that Z is at 5mm and I can manually (long-press on the LCD knob) move the Z-axis back down and the up by 5mm cleanly. From there I can manully raise it to 10mm (for example), it will whir for a couple of seconds as the firmware thinks it's going up to 10mm and from that point I can manually raise/lower by 10mm. I can do this as far as 210mm to get full manual control of the z-axis.
Self-test passes fine.
To me this looks like the firmware not spotting or reporting an error case but I don't know what it might be. The Rambo not detecting the end stops? Bad connections? PINDA not turning on and failing the next step of the calibration but firmware doesn't report it?
Does anyone have ideas?
This is a kit system with the 3.1.1-201 firmware release.
UPDATE: Running bed leveling does give the error "Sensor disconnected or cable broken" - looks like it's a broken cable 🙁