Can't get bed levelling to work properly

General Discussion
1

Basic Information:

Printer Model: Ender 5 s1
MCU / Printerboard: Creality silent motherboard TMC2208
Host / SBC Raspberry Pi 4 B
klippy.log

klippy_latest.log (2.4 MB)

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Describe your issue:

In short: I can’t seem to be able to calibrate the bed properly as the first layer looks inconsistent, with ups and downs right at the start of the skirt path.

The process I have followed is:

  • Start with / without x axis compensation and measure offset with the routine. Noticed that the subsequent bed mesh looks skewed (without compensation) or relatively flat (with x axis compensation), but with similar range of peaks / shape. In this latest calibration I have tried without.
  • Then calibrated Z-offset with paper method, middle of the plate.
  • Then calibrated Bed tilt with Bed screw routine. Brought them all near the reference (screw near 0,0)
  • Then brought the plate to 70 deg C and waited to stabilize
  • Then started the mesh levelling with 9x9, bicubic with 0.2 tension

Once I start the print, I load the mesh with “BED_MESH_PROFILE LOAD=default” through a simple macro, and start printing (at the exact same bed temperature). Then mess happens.

For completeness, this is my typical x axis compensation values.

## [axis_twist_compensation]
## z_compensations = 0.047708, 0.013333, -0.061042
## compensation_start_x = 3.0
## compensation_end_x = 207.0

Any help?

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4

Have you already tried to get the bed as flat as possible?
0.31 mm is quite a bit.
If you have a removable steelsheet, you can try this: https://www.youtube.com/shorts/wIgjtct0GxE

1 Like
5

It also may be worthwhile to run a mesh without the buildplate (unless you’re running an inductive probe). You can sand down the high spots using a sanding block.

6

Thank you for your help. I have tried flattening the bed and re-calibrated from the start. This time with x axis calibration, z-offset, z screw calibration, and 9x9 bed mesh. The mesh looks indeed better, and without that weird bump. I still don’t get perfect bed adhesion, but it’s a good start.

I am wondering if it’s still down to mesh approximations. Perhaps i’ll retry with “mesh_pps” higher than 0?

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