Heightmap being applied but having issues

[mher]

To start off
I'm running a RatRig V-Core 500 with a klicky probe
I'm probing a mesh of 9 x 9.

The heightmap has a max difference of 0.538, I've verified that the mesh is being applied by taking a look at the compensation type which is set to mesh

However I'm having issues the moment I try to print on the entire bed. On certain ends of the bed it'll be way to close to the bed while on other sections it will be so far that the plastic doesn't stick at all.

I noticed the deviation in the object model stated 0.119 and the mean -0.033
I'm hoping someone here can point me in the right direction of solving the issue so i can start printing on the entire bed. Right now it's just not possible due to these issues.

[infiniteloop]

@mher

The heightmap has a max difference of 0.538

That's not bad. Just my two cent: possibly, the bed is not well levelled. The surface looks quite flat, except of the rear left - you should look for potential reasons of the blue bump with the mechanics of all axes.

However, given the overall flatness of the print bed, you should be able to put down a first layer without any mesh compensation. Instead, use the good old paper-sheet method to manually level the bed, then try some first layers. If that works, you can have a detailed look at your levelling routines - maybe they need multiple tramming iterations.

[mher]

@infiniteloop
I'm honestly unsure where the issue is coming from in the back.
I'm running a G32 before every G29 so the bed is being trammed before probing.

However I did just notice one of the arms holding the bed is cracked which might be causing some issues. I'll print those again and see if that changes anything.
The z offset is also set by using feeler guages so that really shouldn't be the issue either.

If the arms isn't what is causing the low spot I have one other suspect and that is the 1.2mm piano wire that i'm using for my umbilical cord. It might be to stiff causing the carriage to be slightly tilted when it's in a certain position. But honestly it seems unlikely that that is the issue, because I would expect the entire back row(s) to suffer under this

[infiniteloop]

@mher Good idea to check the mechanics. Please let us know what happens if you have fixed these issues …

I'm running a G32 before every G29 so the bed is being trammed before probing.

For testing, you should remove G29 and level the bed manually (it’s a pain, I know). By this, you can verify proper function of your bed.g macro.

[Phaedrux]

Usually when the mesh isn't being applied as expected it's due to mechanical issues causing the mesh to vary from reality. Usually probe tilt that varies with XY position or skew in the XY axis.

A cracked arm holding the bed is a good candidate.