I've been using UBL for a long time now and I'm on the Marlin 1.1 bugfix branch.
In my configuration.h file, I have ENABLE_LEVELING_FADE_HEIGHT defined. The default fade height is 10 mm. So once the Z is >= 10, no more bed leveling compensation will be done.
This is easy to see. If you set UBL active, then after homing raise the carriage to Z=10.0, and execute moves around the build area, you won't see any visible Z compensation happening. If you move to Z=2.0, you will see the Z compensation working.
So, let's say I just homed, so I'm at X0, Y0, and Z2. Now I raise the carriage to Z10, and do a G1 X185 Y185. There was no change in the Z compensation on that move. Now if I lower the print head to Z0, does the Z compensation get applied? If it does, then theoretically, I should be able to check that point with my feeler gauge and it should still be the same as when I did the initial mesh calibration.
Also, if I want to do some G29 P4 fine tuning of the mesh, should I deactivate UBL first and re-home before attempting this, or does the code automatically figure it out?
In my configuration.h file, I have ENABLE_LEVELING_FADE_HEIGHT defined. The default fade height is 10 mm. So once the Z is >= 10, no more bed leveling compensation will be done.
This is easy to see. If you set UBL active, then after homing raise the carriage to Z=10.0, and execute moves around the build area, you won't see any visible Z compensation happening. If you move to Z=2.0, you will see the Z compensation working.
So, let's say I just homed, so I'm at X0, Y0, and Z2. Now I raise the carriage to Z10, and do a G1 X185 Y185. There was no change in the Z compensation on that move. Now if I lower the print head to Z0, does the Z compensation get applied? If it does, then theoretically, I should be able to check that point with my feeler gauge and it should still be the same as when I did the initial mesh calibration.
Also, if I want to do some G29 P4 fine tuning of the mesh, should I deactivate UBL first and re-home before attempting this, or does the code automatically figure it out?