I have issues with UBL not seem to correct at all

Hi all,

I have Marlin 1.1.9 and I have an inductive sensor, and I managed to get to this result with G29 P1:

Recv:         0       1       2       3       4       5       6       7       8       9
Recv:  9 | +2.287  +2.817  +2.732  +2.668  +2.622  +2.417  +2.455  +2.257  +2.250  +2.195
Recv:    |
Recv:  8 | +2.242  +2.762  +2.695  +2.630  +2.575  +2.417  +2.455  +2.257  +2.250  +2.195
Recv:    |
Recv:  7 | +2.197  +2.707  +2.657  +2.592  +2.528  +2.425  +2.528  +2.305  +2.387  +2.267
Recv:    |
Recv:  6 | +2.120  +2.670  +2.592  +2.572  +2.512  +2.443  +2.492  +2.330  +2.342  +2.315
Recv:    |
Recv:  5 | +2.105  +2.660  +2.505  +2.562  +2.475  +2.405  +2.457  +2.298  +2.305  +2.260
Recv:    |
Recv:  4 | +2.210  +2.702  +2.542  +2.622  +2.517  +2.410  +2.540  +2.305  +2.298  +2.225
Recv:    |
Recv:  3 | +2.310  +2.673  +2.657  +2.640  +2.550  +2.510  +2.582  +2.347  +2.335  +2.260
Recv:    |
Recv:  2 | +2.265  +2.673  +2.665  +2.640  +2.585  +2.463  +2.552  +2.370  +2.250  +2.207
Recv:    |
Recv:  1 | +2.372  +2.747  +2.707  +2.677  +2.665  +2.492  +2.585  +2.423  +2.298  +2.255
Recv:    |
Recv:  0 |[+2.253] +2.685  +2.653  +2.710  +2.582  +2.467  +2.590  +2.523  +2.312  +2.253
Recv:         0       1       2       3       4       5       6       7       8       9

Based on the documentation and guides available for UBL, I have followed the following sequence:

1. Enabing UBL in the firmware
2. Run G29 P1
3. Then run G29 P3 to fill the blank spots
4. Once I'm done with a good result, I did G29 F10, G29 S1, G29 L1, G29 A
5. Then M500, M501, G28
6. I wanted to show 0 for the z-axis while homed, so I typed G29 P6 Cxx whatever shown on the LCD, then M500, M501, G28 - so that I got 0 for z-axis value
7. I then did the printing height by:
   
   1. Moving the print head to the middle of the bed
   2. Slowly lowering the nozzle until I got it at 0.1mm above the bed
   3. Then again did G29 P6 Cxx whatever number that was showing on the LCD now
   4. M500, M501, then G28
   5. Then tested a few times to make sure it is good
8. In my slicer, I added G29 L1 and G29 A after the G28 command so that the UBL system gets activated.

After all the above, I don't seem to get a good first layer because as you see there is a warp in the bed and I was expecting that the levelling that I've done would correct this however where the warp is, I see the layer line squished and on the opposite side I see it actually thin and not really pushed to the bed.. I tried to observe the z-axis motors to see if any corrections are happening, but they just did not move for the whole first layer..

So is there anything of what I've done above not right? Or it is actually working but my bed is so badly bent that I need to replace it?

Appreciate any inputs or feedback on this!
Regards

Do you have a Delta or some other type of printer?

For a Delta I suggest using UBL, for other machines I suggest using a different method where you probe nine points before each print.

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http://www.marinusdebeer.nl/

Hi,

Well I don't have a delta, it is a square bed with 2 z-axis steppers that drive the carriage up and down and the bed only moves for y-axis.

The full physical bed size is 315x315

I have another issue as well.

I have an inductive probe, and I configured to trigger approximately when the nozzle is 4mm above the glass, so I configured the z offset for the probe to -4.

When I build the mesh and save it, I home the printer, and at home, the nozzle is 3-4mm below the bed, then when I want to manually adjust the bad points in the mesh, I go to the menu, and find the mesh edit commands in the UBL menu and select it. The nozzle will immediately move to the first point without even lifting Z up so it hits the bed and the whole x-carriage will be just forced to lift up in its place and be tensioned while what should happen is that the nozzle should be moved up first then it should go to the first point to edit it..

I'm attaching the configuration.h file, not sure if I have anything done wrong with the configuration or anything. Physically the z-end stop will put the nozzle below the bed, so should I raise that to have the nozzle at the same level of the bed?
Configuration.h

Appreciate your feedback!
Regards