Z 0 is positive

[tecno]

I have new printbed and have issues to get levelling to work.

I get positive values with G30 S-1. What can I have done wrong?

[tecno]

Here another odd number, where does it come from? Trigger height 7.843

[tecno]

I have managed to get a negative Z0
Config = G31 P100 X0 Y0 Z-0.557

When I run G30 S-1 after reboot I get following result that is confusing.

So what is wrong here?

[Phaedrux]

Can you give us some more context to your method?

[tecno]

@Phaedrux

https://docs.duet3d.com/en/User_manual/Connecting_hardware/Z_probe_testing

Calibrate the Z probe trigger height

[luca Massimiliano]

@Phaedrux said in Z 0 is positive:

Can you give us some more context to your method?
SEND ME MORE MATERIAL

[tecno]

@luca-Massimiliano

Hi Luca, what material?

[tecno]

; Z-Probe
M558 B1 P8 R0.4 C"io3.in+io4.out" H15 F1500 T12000
G31 P100 X0 Y0 Z-0.557
M557 R225 S100

[Phaedrux]

How are you setting Z0 before measuring the probe offset?
How are you determining Z0 before creating the mesh?

[tecno]

@Phaedrux

home
move z down to get 0
g92z0
A few g30 s-1 to see that it is same
open config.g
edit G31 line with offset
save and M999

See to that no compensation is active M561
G29

[luca Massimiliano]

@luca-Massimiliano NO IT'S NOT ENOUGH I WANT TO SEE THE POINT QUOTAS OF YOUR PRINTING PLATE EACH POINT YOU SEE CORRESPONDS TO 3 CORDINATES OK?

[luca Massimiliano]

@tecno

[luca Massimiliano]

@luca-Massimiliano

[luca Massimiliano]

@luca-Massimiliano EVERY POINT IS THE POINT WHERE THE PROBE BEATS OK FRIEND?

[luca Massimiliano]

@luca-Massimiliano EVERY POINT IS THE POINT WHERE THE PROBE BEATS OK FRIEND?

[luca Massimiliano]

@luca-Massimiliano FRIEND SORRY I HAVE TO GO NOW EXCUSE ME BYE

[luca Massimiliano]

@luca-Massimiliano Phaedrux KNOWS MUCH MORE THAN I

[Phaedrux]

@tecno said in Z 0 is positive:

save and M999
See to that no compensation is active M561
G29

Try doing a single G30 at the center of the bed before sending G29 to create the mesh.

You should probably also redo your G32 first.

[tecno]

@Phaedrux

After a lot of tweaking this looks to be the best I can get.
Every adjustment of the plate (3-points) a G32 is a must, G30 and then G29.
Picture below is with 60°C heated bed.

New 8mm thick fine milled cast aluminium plate Ø600mm, what can I expect to get in flatness?

Cheers
Bengt

[infiniteloop]

@tecno

8mm thick fine milled cast aluminium plate Ø600mm, what can I expect to get in flatness?

That’s a good flatness, except of the front/left and rear/right - hmmm - "corners"?. For a Delta, a square grid as you’ve pictured is inappropriate. See M557: Set Z probe point or define probing grid for details. Instead of defining the grid by X/Y, use R to set a radius.