g29 probe punching through bed
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@n00dle see my previous post, which I was editing at the same time as you replied.
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@dc42
rgr, i'll change the Z0.7 to Z-0.7 and see?
Sorry, I'm completely lost so if I'm missing something just throw something at me. -
@n00dle Your telling the machine the Z0 is 0.7mm below the probe point, so it will keep going into the bed at Z0..
You need to set it to G31 K0 P500 X0 Y0 Z0. Using an endmill as a probe, means there is no Z offset. -
@stephen6309
That's what i thought but apparently not! Setting Z to 0 just kept driving the mill into the board even though G30 works find, and the normal Z probe to set 0 worked fine.@dc42
Setting Z to -0.7 seems to have done it!G31 K0 P500 X0 Y0 Z-0.7
For my sanity how is this helping? and what does it mean for the heightmap? will it be 0.7mm out in relation to the probed Z0?Edited, above hasnt worked
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@n00dle Verify that you have the correct steps per millimeter set for your Z axis.
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@stephen6309
Sorry not really sure how to check that other than when i touch probe the Z axis to 0 it, then raise it 10mm, if i measure the gap it is exactly 10mm so i assume its ok? -
@n00dle Should be. I usually do a longer travel in both directions to make sure.
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@dc42
Sorry mate,
The -0.7 did work but I had put the board up on some springy bits so it didnt keep bottoming out, but now putting the board back on solid ground it's trying to push through again even though it's triggering the probe. Does the -0.7 need refining?Bizzare, going back to how it was working, it is now not working. Where are the matches...
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@n00dle Just a comment. I think it would be better to insert your configuration in the correct files or at least in config-user-settings.g so that you don't lose them between restarts. Also, the order of these commands are sometimes important.
There you can also comment out and keep track of history as you do your changes.
Only need to remember to either execute the changed files with the M98 command or restart the board (M999) to make the changed take effect.
You can do that, edit the configuration files, in your version of the DWC?
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Ok, figured it out!
When I probe Z with the web interface, it zeros Z for the tool position, not the machine position. This results in the tool position being X0 Y0 Z0 but machine pos is X855 Y995 Z30.
Running G29 works off of machine position hence it pushing all the way through, it thinks it has to go another 30mm.
Running G30 sets the machine Z to 0 and all works as desired. I feel rather stupid but who'd have thought doing a Z touch wasn't enough!
I guess i didn't process that Gcode is run off of tool position so the web interface Z touch isn't the correct way to work with G29.Thanks to all who have responded. And for reference G31 K0 P500 X0Y0Z0 works fine, didnt need the -0.7 on the Z like we suspected.
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@gixxerfast
Yea, i can change the config files easily.So i should put this in the probe config
M558 K0 P5 C"!e0stop" H5 F120 T300 G31 K0 P500 X0 Y0 Z0
and this in the config
M557 x850:1030 y990:1120 S8:8
(or just dump all three lines in the config-user-settings.g file)
Which will allow me to just run G29 S0 at anypoint?
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@n00dle
Well, this beeing a CNC makes me a bit unsure but as far as doing a bed mesh in general.When G29 is executed, if there's a file called mesh.g in the /sys directory it's content will be executed so if you need to others things done as adjusting stepper current, probeing speed or setting the Z0 datum, it can be done in there.
Here's some good documentation regarding the mesh calibration. Read this part also:
"Establish a Z=0 datum using the Z probe" in here https://duet3d.dozuki.com/Wiki/Using_mesh_bed_compensation
As I only have 3d printers (yet) I don't know much about CNC configuration unfortunately.
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@n00dle said in g29 probe punching through bed:
When I probe Z with the web interface, it zeros Z for the tool position, not the machine position.
If you are probing with the tool itself, yes that is what will happen. You might want to include a G31 Z command in each of your tpost#.g files, to set the Z probe trigger height to be the negative of the tool Z offset.