With the upgrade from the Prusa Mk3 to Mk3.5, the bed leveling support in Octoprint is unfortunately no longer available.
Some have problems with the new expansion joints on which the print bed is mounted. Therefore, the silicone or nylock mod is still a good and important thing to generate a very even print bed. Here I show you how it is possible without the Octoprint plugins.
If you are mainly using PLA, heat the extruder and the heating bed to 170 °C/60 °C. Wait 1-2 minutes to avoid temperature fluctuations. (This should be done after each setting in order to obtain correct measurement results).
Use Terminal of Octoprint or Pronterface:
Send "G28" (Homing)
Send "G29 P1" (Meshbed leveling 7×7)
Send "G29 T" (Get the meshbed results)
We now have a list of data. Copy this into a text editor. It should look like this:
Now we take the 3×3 measuring points marked in red from the list. (See picture)
Insert the 9 values into this list:
0 1 2
2 | -0.045 -0.044 -0.028
|
1 | -0.033 -0.048 -0.028
|
0 | -0.033 -0.040 -0.048
0 1 2
Now simply insert the small list on this website: https://bbbenji.github.io/PMSBLM/
There you can now see how the screws of the Nylock mod have to be adjusted.
Repeat this process until you achieve a maximum difference of approx. 0.035 mm or better.
The first layer must then be recalibrated.
I recommend printing this out to check: https://www.printables.com/model/36706-bed-level-test
PS: If anyone is interested in the Prusa Leveling Guide https://github.com/scottrini/OctoPrint-PrusaLevelingGuide can program MK3.5 support, that would be mega nice 😀
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