G32 Cartesian

Siopshop

Hello,

I have a cartesian bed slinger with a 310x320 bed. The z motors are independent and I’ve been wanting to implement G32 before i G29 so that the gantry is level before mesh bed levelling .

Ive whacked the leadscrew positions in (m671) and set the probing points in the bed file with g30 commands.

I was wondering where is best for me to probe. At the middle of the bed each side of the x gantry or probe at the adjustment screws in each corner

If the latter is the case, the probe cant reach the left side screws. What should i do in this instance

Regards

Iwan

fcwilt

@siopshop

The middle of the bed on each side should be satisfactory.

Frederick

dc42

@siopshop you can probe anywhere you like and the firmware will compute the corrections. We normally suggest probing close to the bed mounting points.

Siopshop

@dc42

Thank you kindly. Works a treat on the X axis. Will give the adjustments positions a go also.

Ive added a G29 into the bed file after the probing as if it were a macro when I G32, Is this ok ? Prints are coming off nicely and bed seems very level after adjust from the mesh.
I only ask as I’ve never seen a Z adjust notification in commands.

fcwilt

@siopshop said in G32 Cartesian:

Ive added a G29 into the bed file after the probing as if it were a macro when I G32, Is this ok ?

It's your printer and you can do whatever you want. As long as you are happy with the results how you achieve them doesn't really matter.

That said G32 is associated with Bed Leveling (Auto or Manual).

G29 is associated with Mesh Bed Compensation.

They are two very different things.

Bed Leveling is something that is done before printing, possibly part of homing Z.

Mesh Bed Compensation is a feature that is used during printing to try and compensate for bed irregularities.

G32 executes bed.g where you can put all of the commands needed to level the bed.

Current firmware has G29 execute mesh.g where you can put all of the commands needed to create the heightmap needed for mesh compensation.

Since the two features are very different I keep them separate by using bed.g and mesh.g as intended.

I include G32 as part of the Z homing process.

I don't run G29 at the start of a print because I create heightmaps using dense grids (200, 300, 400 points). That takes a while and once created If your printer is stable you can use the same height map for all subsequent prints.

So I have a macro that I execute manually to create the height map. And in the print start code I have a G29 S1 which loads the already existing heightmap.

Frederick

Siopshop

@fcwilt
Ye should for sure tidy it up. Thanks