Yes it can all be a bit overwhelming.
Here's what I would use for homeall.
; homeall.g
G91 ; relative positioning
G1 H2 Z5 F6000 ; lift Z relative to current position
G1 H1 X-805 Y-505 F800 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 X5 Y5 F1800 ; go back a few mm
G1 H1 X-10 Y-10 F360 ; move slowly to X and Y axis endstops once more (second pass)
G90 ; absolute positioning
G1 X320 Y220 F4000 ; moves probe to approximate bed center.
G30 ; home Z by probing the bed
G1 X0 Y0 Z5 F4000 ; return to origin position
Removed the H2 from the XY moves.
Removed the G92 to force a position. The position will be determined by the M208 minima value set in config.g
Changed the probe position to match your homez.
In bed.g you need to specify two points close to the lead screws to probe and a command in config.g to tell the firmware where those lead screws are located.
Example here shows what you need.
https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors#Section_Example_for_2_motors
Final bed.g would look something like this (with your actual positions)
; bed.g
M561 ; clear any bed transforms
G28 ; home all
G30 P0 X20 Y100 Z-99999 ; probe near a leadscrew, half way along Y axis
G30 P1 X180 Y100 Z-99999 S2 ; probe near a leadscrew and calibrate 2 motors
G1 X320 Y220 F4000 ; moves probe to approximate bed center.
G30 ; probe the bed
G29 ; create a mesh grid
G1 X0 Y0 Z5 F4000 ; return to origin position
@wingtip said in Another mesh bed leveling thread...:
And still wondering what spacing you guys suggest on the probing. Currently i have it set to 20mm. On a bed thats nearly 800x500 that could be a lot of probes??
You're limited to 441 points, so if you set a very low spacing in your m557 command and send it in the gcode console (like 1mm) it will tell you what your minimum spacing would be to stay within the limit.
It's also possible to use number of points to probe and it will figure out the spacing to get that number of points.
M557 X15:630 Y15:415 P10 for example will probe a 10x10 grid.