Probe XY offset - Best Practice?

[JohnOCFII]

Greetings,

In the files delivered with the T3P3 Kossel Mini v3, the G31 X and Y offsets are set to 0, and the comment implies that is intended:

config.g

[[language]]
G31 X0 Y0 Z1.8 P500			; Set the zprobe offset and threshold (put your own values here). For a delta, use zero X and Y offset and measuere Z.
 

bed.g

[[language]]
G31 X0 Y0		; don't want any probe offset for this
 

But the X and Y offset is entered into the actual probe points in bed.g:

bed.g

[[language]]
; Probe the bed and do 6- or 7-factor auto calibration
; bed.g file for RepRapFirmware generated by http://escher3d.com/pages/wizards/wizardbed.php
; 10 points, 6 factors, probing radius: 85, probe offset (11, 0)
 

Is this still the preferred approach, as opposed to setting X and Y probe offsets in config.g's G31 command?

Thanks,

John

[JohnOCFII]

Any suggestions on the most preferred way to represent XY probe offset?

Thanks,

John

[dc42]

The comment about setting the probe offset to zero for a delta is obsolete. Unless you are using very old firmware, you should use the actual probe offset in config.g and not change it in bed.g.

[JohnOCFII]

@dc42:

The comment about setting the probe offset to zero for a delta is obsolete. Unless you are using very old firmware, you should use the actual probe offset in config.g and not change it in bed.g.

Thanks for the clarification, David.

[JohnOCFII]

@dc42:

The comment about setting the probe offset to zero for a delta is obsolete. Unless you are using very old firmware, you should use the actual probe offset in config.g and not change it in bed.g.

Thanks again - I just noticed this advice about XY in G31 is still in the Wiki - you might wish to update: https://www.duet3d.com/wiki/Configuring_RepRapFirmware_for_a_Cartesian_printer

The G31 command also has also optional X and Y parameters to define the horizontal offset of the Z probe from the nozzle. On a delta printer these should be left at zero, because the calibration routine needs to know where the nozzle has been placed, not where the probe is.

[dc42]

Thanks, I've just updated it.