@mikeabuilder

I finally found time to do your very helpful scientific experiment.
Was to complicated for me. 😄

But for anyone else having this problem:

My z axis minimum was set to z0

Changing M208 for Z0 to Z-2 in config.g was finally solving the problem.

@atall thank you all for your great and quick help, tips and tricks.

After 10 months of guessing and time consumable troubleshooting I am finally able to use my most expensive printer!

hooray!

@merlin246 perhaps use

M376: Set bed compensation taper

Then after the taper height I guess there shouldn't be any mesh related z moves for the rest of the print?

Just a thought...
Cheers
Barry M

@phaedrux It seems to be working at this moment. I printed the STL that you sent over and seems to be behaving, although I'm still seeing very very slight variations in layer width across the bed, it's good enough for the time being to move forward and work on pinpointing some of these issues in getting my Z=0 datum set correctly.

@thepfeiffenator looking at the mesh, i would try some physical leveling too. Either the X is tilted or bed is physically tilted. the less compensation the better. just because it compensates doesn't mean it always should 🙂

@cncmodeller
Thanks for the warm words.
The Slider is pretty small and I will mount a hotend with Bowden extruder at most. The hole pattern is 20x20mm.
But the concept is scalable. You can use bigger Delrin or PTFE rods to beef it up.
A few years back I tried to build a Delta printer with such sliders, not sure why I stopped.

@Veti that's a very good point.

Fixing it to the correct values, there is no more error.
G31 P500 X-22 Y0 Z0.1

Thanks for pointing that out!

I think the PETG available today is generally as easy to print as PLA. Hotter temps and less cooling are the big differences. Otherwise most print settings can remain the same.

Tried a mesh compensation with a piece of paper, disastrous results, here's a picture:

Heat paper.png

@taconite said in bed mesh compensation unclarity:

Question: Why is it not possible to load a previously saved height map, without establishing the Z=0 datum? Because of the homing of the axis the position of Z=0 should be the same (Ignoring possible jitter in the homing switches).

on a delta this should still work. if you just ignore the message you should be able to print just fine.

https://www.dropbox.com/s/xlzhcwm6c8qfyar/benchy_not working.gcode?dl=0
https://www.dropbox.com/s/2kg1cpzdxq78m8h/benchy_working.gcode?dl=0

Hi @dc42

I am sure I was doing that. I will have another go at it tonight.

Kind Regards,
Sam