Hi guys i have got auto bed leavening kind of working on my prusa

3D Printing
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1

Hi guys i have got auto bed leavening kind of working on my prusa i3… i followed tom’s youtube guide.

found my z offset was 0.9, put this in the marlin firmware as below

“#define Z_PROBE_OFFSET_FROM_EXTRUDER -0.9”

Now after a g28, and g29… the head is still sitting 0.9mm to high, if i put this in to my slicer G92Z0.95 after a g28 and g29. All goes well.

Shouldn’t “#define Z_PROBE_OFFSET_FROM_EXTRUDER -0.9” mean i don’t need to do this?

After running a g29 i get this line back

SENDING:G29
Bed x: 59.00 y: 50.00 z: -0.44
Bed x: 218.00 y: 50.00 z: 0.17
Bed x: 218.00 y: 151.00 z: 0.27
Bed x: 59.00 y: 151.00 z: -0.36
Eqn coefficients: a: 0.00 b: 0.00 d: -0.72
planeNormal x: -0.00 y: -0.00 z: 1.00
echo:endstops hit: Z:-0.35

Does the endstop hit z:-0.35 stop the offset working? as the inductive probe is the ends top i can’t stop this can i?

2

I suffered from exactly same issue for couple of days. I can not get my nozzle closer to bed no matter what value I put into Z_PROBE_OFFSET_FROM_EXTRUDER.
And I also want to know what value after Z exactly means, after G29 or G30.

3

Yes I am still having the same problem also…hmm

4

So that’s been documented issue in marlin for about a year now. I just finally quit using auto leveling until they fix it.