Live Z increases with every print  

Re: Live Z increases with every print

Check your PINDA sensor. It may be loose.

Re: Live Z increases with every print

The PINDA is fine, and after a cold reset the values are fine again (but then start again to increase from print to print).

It seems that I am not the only one experiencing this: https://shop.prusa3d.com/forum/general-discussion-announcements-and-releases-f77/live-z-increases-from-print-to-print-software-bug--t25752.html

Re: Live Z increases with every print

I had the same problem.
Somehow I had lost the Z calibration by doing something when I first started using my printer.
If you run the Z calibration procedure (up to the top, rattle, etc), you must then run the V2CalibrationZigzag using PLA. It is at the end of this routine that a value is stored to non-volatile memory. Unless this value is stored, I got the same situation that you are getting now.

I do not know if it is an offset value that is stored or merely a flag to say that Z is now calibrated, but you have to do it.

That is what Bill Campbell was telling you in the other thread.

I have no idea how this is or isn't connected to Octoprint.

Nevertheless, it is easy, quick and painless to run the V2Calibration routine, it is stored in the machine and accessed from the front LCD panel now.
Worth trying.

Re: Live Z increases with every print

What was your Firmware version. You may want to compare all software versions in case the issue is being caused by lets say the Slic3r version and MK3 firmware version.

Re: Live Z increases with every print

What was your Firmware version

Firmware is 3.1.0

I have re-run the calibration V2 after running the setup wizard, and for the moment things look fine.

However, I had run the V2 calib. after assembling the printer. If indeed something special was stored during this routine (except a flag that it was run), then it was definitely lost or altered later, which should not have happened IMO.

Also, I really would like to understand what that setting would be. My understanding is that the steppers run the carriage into the end switches to determine the home (zero) position for the X and Y axis, and that the PINDA probe sets the zero positon for the Z axis.
To this Z zero position (which really is the interpolated bed plane) the live Z offset is added during printing.

What additional settings could there be that "break" this referencing in X/Y/Z space?

Re: Live Z increases with every print

Again confusion between different unrelated settings.

Z offset is a number you enter in Slic3r settings and is used to compensate the difference in Z height needed for different types of filament without altering live Z setting.

Live Z as I said before is a measurement specific to your printer, that is only stored into EEPROM when the machine state has been set to tell it to record changes. It is the most important calibration of all in regard to filament adhesion to the bed.

The PINDA is not checking height, it is mapping bed level variances.

Re: Live Z increases with every print

Again confusion between different unrelated settings.

Actually, no.

I did only refer to the live Z that is made with the rotary knob while printing. I have not made any adjustment in Slic3R, nor did I refer to these.

Live Z as I said before is a measurement specific to your printer, that is only stored into EEPROM when the machine state has been set to tell it to record changes. It is the most important calibration of all in regard to filament adhesion to the bed.

I think nobody disagrees about this.

The PINDA is not checking height, it is mapping bed level variances.

It depends on what you mean with "height" (I did not use this word).

In addition to measuring bed unevenness, I think iit also is used to home the Z axis (which has no mechanical end switch). In that sense it also sets the origin of the Z axis. Therefore, in absolute terms, it sets some "height offset" (in the sense of an absolute mechanical position on the Z axis).

Re: Live Z increases with every print

Well you did say that running First Layer Calibration as suggested resolved your problem, so the continued misuse of terms is thankfully not affecting your ability to print.

Good luck and happy printing.

Re: Live Z increases with every print

Well you did say that running First Layer Calibration as suggested resolved your problem, so the continued misuse of terms is thankfully not affecting your ability to print.

I am not sure what to say about your posting style...

What annoys me is that you write very general and sweeping statements about what you thnk is a misuse of terms (I don't think I actually did, or if I did in you opinon it was absolutely clear what I meant). You also did not contribute anything to a solution or what would help to understand the original problem.

Yes, it works again, after resetting the printer and re-running the wizard. I do not know whether it was the first layer calibration.

I still thing there is a bug somewhere because such a drifting Z should not occur.

Re: Live Z increases with every print

Whilst you are annoyed that I think it important you do not confuse terms, I am mildly upset that when I gave you the solution (run first layer calibration), you chose to ignore me because you could not understand the information you were being given.

Bottom line, I am pleased you have resolved your printing problem. That is what this forum is about.

RE: Live Z increases with every print

I am facing the same problem... After reading your posts, I am not sure this helps to solve the problem.

Is it possible to know what is really the problem and how is it possible to fix it?

Thks.

NB

RE: Live Z increases with every print

Posted by: @nicolas-b

I am facing the same problem... After reading your posts, I am not sure this helps to solve the problem.

It would be helpful if you'd summarize what you have already tried and what settings and software you're using. Running the on-board Live-Z routine initializes the firmware setting and keep it from drifting. Have you tried that? What firmware are you running? Have you flashed new firmware recently? Give us some context to help you.

RE: Live Z increases with every print

This defect is in the firmware; the only way to avoid it is:

1.  You must do a Calibrate:Live-Z at least once;
2.  Force a mesh level before each print using the G80 command in Start-up Gcode.