Possible bug in Live Z Adjustment?
I've just finished building my Prusa MK2 from the kit. When trying to do fine adjustment on the Z axis I attempted to use the Live Z adjustment as I saw on one of the videos, however when I turned the knob, the adjustment value jumped up to 6mm and the head plowed into the bed, damaging the PEI coating (it's quite badly rippled). I frantically tried to adjust it back to 0, but it did not adjust quick enough, so I hit the reset button to stop further damage.
1) I'm not sure what to do with the damaged PEI - is there a way to fix it?
2) I'm too nervous to try that live adjust function again! Is there a firmware fix for that?
EDIT: Oops - I see I put this in the i3 sub forum, not the MK2 one.
Re: Possible bug in Live Z Adjustment?
Hello David,
you can check settings of live Z adjustment by going to ->Settings->Live adjust Z. This can be done without running auto-calibration or printing any model, it simply adjusts Z axis. Please check value you have ( 6 mm is rather strange number ) - dial in to have 0 mm before going into any other attempts to calibrate. Once you have 0 mm there double check height of the nozzle above heat bed and adjust as necessary. Restart the printer and double check - Live adjust Z must be 0 and nozzle in height as you adjusted. If so I believe auto calibration will be sucesfull.
Re: Possible bug in Live Z Adjustment?
I was not clear in my post. When I went to the Live Adjust function the initial value was 0, however as soon as I turned the knob it immediately jumped to 6mm and started digging in to the plate. There was some sort of glitch I'd imagine, because setting it back to 0 took many turns!
I was using the original Z calibration gcode at the time - I'm not sure if there is some sort of glitch that can occur if adjusting between the calibration circles?
Re: Possible bug in Live Z Adjustment?
Understood. My main point was to check and correct live Z value to 0 or any reasonable number before proceeding with next calibration. I don't think this is coming from original calibration code during picking up correct circle. Have you tried V2 calibration ?
Re: Possible bug in Live Z Adjustment?
Hello,
As a point of information, I had the same thing happen too. Using the correct firmware and everything else looked good. I was told that PEI will be available for sale within the next couple of weeks.
tarek : )