Mesh bed leveling - a tad confused

Phil Maddox · 15 Jun 2017, 05:51

Hi all. I currently have a duet wifi running on a i3 Steel cartesian printer
I have a DC42 IR sensor all set up and working fine on a heated bed with a Zebra skin ( PrintinZ)
im currently using "bed compensation" set up in the bed.g file which works fine but i feel bed mesh leveling would be better ( the Zebra skin isn't exactly flat especially after months of prints and flexing to remove)

My question > If i wanted 9 or 16 point leveling what is the most straight forward way to achieve this ?

Thanks in advance

Phil
PS apologies if this has already been covered A link to the relevant thread would be much appreciated

dc42 · 15 Jun 2017, 06:06

See https://duet3d.com/wiki/Using_mesh_bed_compensation.

Phil Maddox · 15 Jun 2017, 07:23

Thanks just what i needed.

Just to double check
when using the M557 command
1/ are the XY coordinates stored or does this need to be done every power cycle?
2/ are the coordinates for the probe or the nozzle ? ( is the probe offset accounted for) ?
Thank you

dc42 · 15 Jun 2017, 09:08

1. M557 should be put in config.g because the coordinates are not stored independently of the height map.

2. The coordinates are for the probe, because the probe offset is accounted for.

whosrdaddy · 15 Jun 2017, 09:42

1/ adapt config.g to include M557
2/ you specify the probe offset relative to the nozzle with the G31 command.

Phil Maddox · 15 Jun 2017, 16:26

Thank you

robm · 16 Jun 2017, 05:03

Ah!
After running the bed compensation you still need to load the map before a print or in config.g (G29 S1 / M375) and it is not there by default or just by running mesh compensation.
Don't know why I didn't think of it before; guess it shows I have the rest of the system adjusted reasonably well already that this did not matter too much.
Well, at least it is still a pretty graph

dc42 · 16 Jun 2017, 06:15

@robm:

Ah!
After running the bed compensation you still need to load the map before a print or in config.g (G29 S1 / M375) and it is not there by default or just by running mesh compensation.
Don't know why I didn't think of it before; guess it shows I have the rest of the system adjusted reasonably well already that this did not matter too much.
Well, at least it is still a pretty graph

After a successful G29 probing run, mesh bed compensation will be in use. Resetting the printer, or running G32 (for example, to recalibrate a delta printer) will clear it and you will need to run G29 S1 if you want to use mesh compensation without probing again.