Z-offset random failure
I replaced my nozzles of my 5T assembled with Obxidian 0.4s but the z offset calibration is failing on random nozzles each time , like 2,3,4 have all failed on successive runs. Checked load cells and made sure the set screws are snug. Any suggestions? (Yes I can ask support but figured if anyone had a quick suggestion?)
RE: Z-offset random failure
I had that issue, when the nozzle was not fully pushed into the printhead.
RE: Z-offset random failure
You mean the tube needs to hit the top inside the extruder? Or needs to seat on the heater block?
I had that issue, when the nozzle was not fully pushed into the printhead.
RE: Z-offset random failure
The tube end of the nozzle has to hit the top inside in the extruder.
It also has so be screwed in completely into the heater block. I use a torque wrench to make that sure that the nozzle sits fully in the heater block. Prusa suggests 1,5 NM. That might be ok for brass nozzles but ObXidian tend to losen themself due to their coating if screwed in with 1,5 NM. There I use 3 NM as it was with the old V6 hotend on the MK3.
RE: Z-offset random failure
Thanks. I'll try the 3NM torque wrench setting, didn't realize they tend to wind back out (or maybe I've gotten enough gunk filament stuck to the block despite the sock to act as thread locker?)
The tube end of the nozzle has to hit the top inside in the extruder.
It also has so be screwed in completely into the heater block. I use a torque wrench to make that sure that the nozzle sits fully in the heater block. Prusa suggests 1,5 NM. That might be ok for brass nozzles but ObXidian tend to losen themself due to their coating if screwed in with 1,5 NM. There I use 3 NM as it was with the old V6 hotend on the MK3.
RE: Z-offset random failure
Update: All the Obxidians were slightly loose so they all got snugged and pushed up firmly before the set screw was tightened. I think something else is wrong, it started doing it, got through #1, but as soon as it started #2 I watched it reboot the printer and then came up with a fail message. I noticed it rebooting a few times during a later attempt that got to #4 before rebooting. So I suspect something else is failing, unless that is the normal homing fail behavior to reboot the printer?
The tube end of the nozzle has to hit the top inside in the extruder.
It also has so be screwed in completely into the heater block. I use a torque wrench to make that sure that the nozzle sits fully in the heater block. Prusa suggests 1,5 NM. That might be ok for brass nozzles but ObXidian tend to losen themself due to their coating if screwed in with 1,5 NM. There I use 3 NM as it was with the old V6 hotend on the MK3.
RE: Z-offset random failure
So I suspect something else is failing
If it reboots, there is definitively something else which is wrong.
RE: Z-offset random failure
So Support has been helping me debug this, and apparently rebooting on a calibration failure is normal (weird?) per them. I just filmed 2 failed calibrations at their request (one failed tool 2 the second tool 5 literally a few seconds before the entire sequence finished - ugh) although at least the failure happened seconds before the 15 minute limit on single video clips on the iPhone hit. They had me swap the heads to see if the failures followed the heads (given the random nature not sure what that even means). I swapped all the nozzles for fresh brass ones, checked they were snug, checked belt tension and am officially mystified.
Right after that my mk4 began acting up, but that at least was just idiocy on my part, when the magnetic fan was slightly knocked presumably when I popped a part must have bumped it so it hung out (problem of sending print jobs remotely from connect is you won't see such things) and when the printer homed it was unhappy. That at least was a 2 second fix (other than the headache after I facepalmed)🤦♂️
Posted by: @marc-9
So I suspect something else is failing
If it reboots, there is definitively something else which is wrong.
RE: Z-offset random failure
Just to update the final fix, so support worked through some troubleshooting, and ultimately had me reset to factory, and magically worked after that (although the filament sensor on one tool is now “failing” calibration… but other than having to ignore that every print, the machine is back to printing…