Manual bed compensation MAP

Donpi

Hi everyone,

I am facing a little problem with my pritner.

To make it simple my IR Zprob does not work with the black buildtak suface. And my bed is convex.

It sems that at the center the bed is about 0.2 or 0.3 mm higer than the borders. It my be caused by the heater or something.

But at the moment I can't Zprob the bed.
So I wonder if there is a command to set manualy the compensation at three of four points.

Something like :
Mxxx X10 Y10 Z0.1
Mxxx X10 Y190 Z0.1
Mxxx X190 Y85 Z0.1
Mxxx X85 Y85 Z0.6

Someone has an idea ?

dc42

Here are three options:

Set up a bed.g file as if you are using the old 3-, 4- or 5-point bed compensation. In the G30 commands in that bed.g file, instead of using Z-9999, use the actual height error at the probe points.
Set up a grid using M557 and run G29 mesh bed probing. It will generate a heightmap.csv file. You can edit the height errors in that file (in DWC) to be the actual height errors at those points. Use G29 S1 to load that height map file.
Put a piece of paper on top of the buildtak, calibrate the Z probe trigger height when using that piece of paper, set up a grid using M557, and run G29 mesh bed probing. Then you can remove the paper and subsequently run G29 S1 to load the height map file.

BTW it may be that your gantry os sagging, rather than the bed is bulging.