Pro XT Firmware upgrade questions - wiping off side of bed


So the XT has the BL Touch.

Latest version of Cura LE 4.13.4

Pro XT has the M175 tool head.

I made sure the proper things were checked off and updated the firmware.

Upon printer reboot, I keyed in the z offset value. Done.

I had it do the Backlash compensation and the print head crashes down to the right side of the wipe bad, just banging around. It then does the backlash compensation routine.

How do I get that sorted out?

On the plus side, when i hit “Build Mesh” via the menu, it is doing a 5x5 grid. Thank you!

Bumping this - Can anyone offer some advice how to cure the machine wiping off the side of the bed?

I observed this behavior when doing the Backlash Compensation (automatic) and would like to fix it!

Thank you

Since it’s all part of the same routine in firmware, M206 won’t help, as it would adjust the location of both the wipe and the backlash compensation. You’ll have to do custom firmware or wait for the fixed version.

Great. 2 machines down thanks to firmware.

The backlash code is just running G12 to do the wipe. Does G12 by itself not work?

If you take care of cleaning the nozzle yourself and preheating, just run G425 in Octoprint to do the meaty part of the backlash compensation calibration. Be sure to M500 after it is done and add M425 to your start gcode.

Are you using M206 in your start gcode to adjust the wipe position? If so, run the same M206 command through Octoprint and then run the backlash routine.

Failing that, look for LULZBOT_CALIBRATION_SCRIPT in the configuration_adv.h and adjust the command list to do a custom wipe. It’s Lulzbot, if you aren’t fixing their firmware with custom changes you are way too trusting. All my machines run slightly modified stock firmwares.

I don’t think the backlash compensation does anything anyway, it’s marketing fluff.

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I can’t remember what the backlash measurement was last time I ran lulzbot firmware, but I’m 99% sure that it was less than the margin of error expected from hot plastic anyway.

It was useful for getting the offsets in the ballpark with the dual extruder, but your nozzles damn well better be 100% clean of plastic before attempting that one.

Marlin even having this feature is Lulzbot’s doing, if you look through the various Marlin threads around 2018. I believe it started with a concern the belted z axis on the Mini 2 introduced a ton of it and they needed a way to mitigate it.

@LulzMeister maybe you can help me with this issue?

This one is unfortunately a little more out of my wheelhouse, sorry.

One thought that would come to mind is making sure that the Y assembly is attached at the right location in the frame, the left side of the left Y-axis attachment chassis should be 143mm away from the frame when we assemble them. This can be seen here in the OHAI (the jig is 143mm).

If that doesn’t appear to be the problem, zenotek’s suggestions are likely some of the quickest workarounds to the issue, with the bright side being that you should be fine after you run the backlash calibration once. Otherwise, I’m definitely more versed on the software side of things and this is a bit more of a firmware/hardware issue.