Heigh error after calibrating

Stephen6309

@TristanKoeln To get the probe closer to the bed you need to increase the Z offset in G31. Make sure you have homed all the axes. Also make sure you one have one G31.

I use a macro that I call in the slider's start gcode to set G31.
For example:
; CXY-MSv1
G31 P500 X0 Y-60 Z1.98 ; Set Z probe trigger value, offset and trigger height; increase to get closer
M291 P"PETG Offset" S0 T5

I use the paper method to find Z0.

I use this since it's faster to edit macro than waiting for the duet to reboot. I do have a G31 in config.g with Z0 for the offset.

TristanKoeln

@Stephen6309 what do you mean with puting it in a macro to edit it faster?

Stephen6309

@TristanKoeln The code I showed above it in a macro, in the macors folder and it called PETGOffset. In the slicers start gcode I have added: M98 P"/macros/PETGOffset" ; set z probe offsets
to call the macro. Editing a macro is faster than editing config.g and then waiting for the duet to restart after the edit.

Also, I have a different one for setting PLA, since the hotend is at a lower temp than PETG. First line in the macro is the printer's name, since I have two printers.

ziggymanpopo

Another way is to use M564 S0 that will allow you to probe down to the glas it overrided the previous G92 Z0 comand which tells the printer where Z0
Or your bed height is at ....
Checknout the documentation tab on this site (three bars top left)
You will find all of the process under the z prob section look for a link to calibrate z-probe
This link takes you to what you seek
Good luck..

Phaedrux

Post your config.g homeall homez bed.g and start gcode so we can see everything that could be going on in sequence.

TristanKoeln

@Phaedrux here are all my files:
homez.g homeall.g config.g bed.g
Startcode:
M98 P"/macros/PLA_Offset" ;set z probe offsets
G29 S1 ;load heighmap
@Stephen6309 i add the macro thing xD

fcwilt

@TristanKoeln said in Heigh error after calibrating:

Startcode:
M98 P"/macros/PLA_Offset" ;set z probe offsets
G29 S1 ;load heighmap
@Stephen6309 i add the macro thing xD

Adjusting the probe Z trigger height is a curious way to make such an adjustment.

The probe Z trigger height should be a constant that only varies with temperature perhaps.

If you wish to tweak the Z height when printing different materials you may want to use the "baby steps" setting instead - see M290.

You can, if you wish, make use of the filament handling feature of DWC to specify different filaments at the start of a print and obtain different Z height "tweaks" using M290 based on the selected filament.

Frederick

TristanKoeln

@fcwilt thx for you advice, but first i want that my printer prints something befor i will realy start tweaking out some thing, right now my problem is that the nozzel is allways 1-2 mm to high

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt thx for you advice, but first i want that my printer prints something befor i will realy start tweaking out some thing, right now my problem is that the nozzel is allways 1-2 mm to high

OK that should be easy to correct.

One thing you need to remember is that before creating a height map with G29 S0 and before loading the height map with G29 S1 you need to perform a G1 to move the probe to the center of the bed and then do a single G30 to set the Z=0 datum.

And of course for the Z probe to work properly it's Z trigger height value (in G31) needs to be set to the correct value.

Frederick

TristanKoeln

@fcwilt all of that is done see in the homeZ and the trigger hiegh is calibrated with :
Move the nozzel to the middle
G30
than moving nozzel down till it hits the bed
G92 Z0
G1 Z10
G30 S-1

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt all of that is done see in the homeZ and the trigger hiegh is calibrated with :
Move the nozzel to the middle
G30
than moving nozzel down till it hits the bed
G92 Z0
G1 Z10
G30 S-1

That calibration looks fine.

However homeZ.g looks a bit wonky.

I've re-posted it here using the </> tag:

; homez.g
; called to home the Z axis
;
G91               ; relative positioning
G1 H2 Z10 F6000   ; lift Z relative to current position
G1 H1 Z-500 F3000 ;Go down till endstop
G1 H2 Z10 F6000
G1 X200 Y200 F4000 ;go to midle
G30 ; move Z down until the endstop is triggered
G92 Z0         ; set Z position to axis minimum (you may want to adjust this)

; Uncomment the following lines to lift Z after probing
;G91              ; relative positioning
;G1 Z10 F100      ; lift Z relative to current position
G90              ; absolute positioning

This line, which occurs after the G30, may be the cause of your problems:

G92 Z0 ; set Z position to axis minimum (you may want to adjust this)

On my printer, running firmware 3.2.2, after a G30 the Z position is the probe dive height (the H parameter in M558) plus the Z trigger height (the Z parameter in G31).

But the G92 is telling the firmware that the Z position is 0.

Perhaps that is correct for your firmware but it would cause a problem with mine.

Frederick

TristanKoeln

@fcwilt with the G92 Z(dive heigh+triger high)
is still the same problem

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt with the G92 Z(dive heigh+triger high)
is still the same problem

After you performed the calibration routine you posted did you go back and update the G31 command with the correct Z trigger height as reported by the G30 S-1?

Frederick

TristanKoeln

@fcwilt jup its 3.760

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt with the G92 Z(dive heigh+triger high)
is still the same problem

Since the G30 leaves Z at dive height + trigger height setting it again to the same value with G92 is redundant.

It doesn't hurt but isn't needed.

Frederick

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt jup its 3.760

Are you still running the "PLA" macro?

If so what does it look like.

Frederick

TristanKoeln

@fcwilt

G31 X-31.7 Y3,16 Z3,760 P25
M291 P"PLA Offset" S0 T5

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt

G31 X-31.7 Y3,16 Z3,760 P25
M291 P"PLA Offset" S0 T5

And that is the height reported by your calibration routine?

Frederick

TristanKoeln

@fcwilt ya

fcwilt

Hi,

Recall that before creating a height map with G29 S0 or before loading the height map with G29 S1 you need to position the probe to the center of the bed and do a single G30 to set the Z=0 datum.

Having set the Z trigger height to the value as reported by your calibration routine did you go back and re-create the height map using the new value?

Are you also setting the Z=0 datum when loading the new height map?

I mentioned that changing the Z trigger height to accommodate different filaments was not a good approach - one reason being is that it will mess up setting the Z=0 datum which may cause the height map to not work right.

Frederick