(Guide) Swapping from bed.g to 4 point mesh with repeat probes.
November 23, 2018 03:23AM
Hi all.

Just a quick, short post to show what I did to swap from using bed.g to the mesh bed compensation.

Bed.g as was:

M561 ; clear any bed transform
; Probe the bed at 4 points
G30 P0 X65 Y5 H0 Z-99999
G30 P1 X65 Y195 H0 Z-99999
G30 P2 X228 Y195 H0 Z-99999
G30 P3 X228 Y5 H0 Z-99999 S

Critical config items:
M558 P1 H5 F120 T6000          ; Set Z probe type to unmodulated and the dive height + speeds
G31 P608 X0 Y0 Z2.35            ; Set Z probe trigger value, offset and trigger height

Bed.g no longer relavent. Config items changed / added to the following:

M558 P1 H5 F120 T6000 A5 S0.03  ; Set Z probe type to unmodulated (P1). Dive height (H5). Speeds 
                              ; (Probe - F120, travel - T6000). Probe each point 5 times (A5) maximum
                              ; in order to reach 0.03mm tolerance (S0.03).
M557 X65:228 Y5:195 S163:190       ; Define mesh grid (X[min x]:[max x] Y[min-y]:[max-y] 
                               ; S[x spacing of mesh grid]:[y spacing of mesh grid])

The mesh bed is triggered by G29.

Edit: Note: Your target co-ordinates are likely to be different to mine.

Edited 2 time(s). Last edit at 11/23/2018 03:25AM by WesBrooks.
Re: (Guide) Swapping from bed.g to 4 point mesh with repeat probes.
November 23, 2018 05:07AM
I've not deployed this, but an additional note.
The RepRap Firmware Configurator v2 tool creates a bed.g for firmware 2.x that contains

; bed.g
; called to perform automatic bed compensation via G32
;
; generated by RepRapFirmware Configuration Tool v2 on Fri Nov 23 2018 10:04:45 GMT+0000 (Greenwich Mean Time)
M561 ; clear any bed transform
G28  ; home all axes
G29  ; probe the bed and enable compensation

Which makes G32 == G29 (and means you can press the "auto bed compensation button" without having to click the arrow next to it and press "mesh compensation")

Edited 2 time(s). Last edit at 11/23/2018 05:10AM by cheeseandham.
Re: (Guide) Swapping from bed.g to 4 point mesh with repeat probes.
November 23, 2018 07:01AM
thumbs up Like!
Re: (Guide) Swapping from bed.g to 4 point mesh with repeat probes.
November 23, 2018 07:05AM
Cheers for the bed.g mod that makes sense thanks.
Re: (Guide) Swapping from bed.g to 4 point mesh with repeat probes.
November 23, 2018 10:59AM
If your Ormerod had be levelling screws then you might like to set up a bed.g file that tells you how much to adjust them by. See [duet3d.dozuki.com].



Large delta printer [miscsolutions.wordpress.com], Robotdigg SCARA printer, Crane Quad and Ormerod

Disclosure: I design Duet electronics and work on RepRapFirmware, [duet3d.com].
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