G32 doesnt save after True Bed Leveling

droftarts

@johny Ooops! Sorry, the line should be

G29 S0             ; probe the bed and enable compensation

Not just G29, because

In RRF 3.2 and later, if G29 is commanded with no S parameter, then file sys/mesh.g is run if it exists.

If you emergency stop, you should be able to get control back, then change the macro

Ian

droftarts

@johny Did you ever do a mesh by hand? You might believe it's software, but many, many users use bed mesh without problems. I think the problem is the distance the probe is from the nozzle, and they are measuring different things. Probably your bed is flatter than the probe is reporting. You didn't answer my question earlier about the position of the probe, or if you had checked the bed with a straight edge, like a ruler.

Ian

johny

@droftarts
As i understood to make the mesh manually the nozzle will travel to the first position then it waits for me to jog the Z and then I should click somewhere or send some command right? i tried to look for this and didn't found.
I have 3D printers since 2011 and i followed the innovations closely. I have a Cartesian (duet) with BLtouch that works fine, i don't touch the bed for years.
Maybe I need to flash the duet again?

fcwilt

@johny

You have a Z probe and it seems to be working. No point in creating a height map by hand when you have a Z probe.

Refresh my memory - did you ever verify that the Z trigger height setting in the G31 was correct?

You won't get a good height map if that setting is wrong.

Frederick

droftarts

@johny can you take a couple more pictures of your X carriage, ie from the side?
Have you put a straight edge across your bed?

Either the bed is warped, or there’s a difference between what the probe is measuring and how fat the nozzle is from the bed, dependant on the position on the axis.

As I said earlier, for the manual bed probe, use a piece of paper under the nozzle at each point. Move the Z down until it just grabs the paper. Click OK to move on to the next point.

@fcwilt you have missed the point. The probed bed mesh doesn’t match what the nozzle is doing. Getting a manual bed mesh, the comparing it to a probe bed mesh, should show what the difference is. I think the bed is very likely has less deviation than 0.65mm, and the problem is caused by the gantry twisting under the weight of the hotend. Because I think the probe is offset in the Y direction (though the config does not reflect this) it is mismeasuring the mesh.

Ian

fcwilt

@droftarts

I understand your point. I simply don't agree with your theory as to what is wrong.

Getting past "operator error" can be tricky.

Frederick

johny

@droftarts Sorry for the late reply, with the end of the year/vacations, etc I didn't have the proper time to reply and work on this printer problem. Bellow the pictures asked.
The bed is warped (I used a light source below the ruler to see it better but the bed compensation should compensate for that no?)

oliof

@johny with the wrong Y offset of the probe, the compensation applied is wrong.

An exaggerated example: If your Y offset is 40mm physically but you defined your Y offset as 0 in your config, the printer will compensate for what it measured 40mm away

In addition, the further away the probe is from the nozzle, the higher the risk for imperfections in the carriage and probe mount skewing results further.

The recommendations are

a) verify and adjust your Y offset
b) try to reduce the distance between nozzle and probe (verifying and adjusting probe offsets after)

In addition, I recommend to have the Z probe location match a point of your axis alignment and a point of your bed mesh, so you have a physical fix point between the three measurements that should not be further out than your probe repeatability.

johny

@oliof so you saying that G31 has the wrong X and Y values?
G31 P1000 X23 Y5 Z0.1

oliof

@johny I would guess that the center of the probe is rather 50mm away from the nozzle than 5mm in the Y direction guessing from the photo you posted. after all, you have a 20mm extrusion between the two, and both the Z probe and the nozzle stick out. So yeah, that's likely off by a lot.