Heigh error after calibrating

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt the G92 is only in the home all file ;

Just before that G92 Z10 you have a call to homeZ.g which executes a G30 and sets the Z=0 Datum and leaves the Z position at dive height + Z trigger height.

You can't just tell the firmware with a G92 that the Z position is something else and expect things to work.

You can change the actual Z position with a G1 Znnn command but not with a G92 command.

not realy

When you use M401/M402 the firmware keeps track of the state of the probe (retracted/deployed).

When you use the M280 command to retract/deploy the actual state of the probe and what state the firmware thinks the probe is in may conflict and possibly cause problems.

Frederick

TristanKoeln

if im setting all the G92 Z(dive + trigger geigh) could that solve the problem

fcwilt

@TristanKoeln said in Heigh error after calibrating:

if im setting all the G92 Z(dive + trigger geigh) could that solve the problem

Hi,

You don't need to.

The G30 leaves the Z axis position at dive height + Z trigger height.

Setting it again with G92 to dive height + Z trigger height is redundant and serves no purpose.

G92 is useful in certain specific instances and unless you are dealing with one of those instances you should treat the presence of G92 in your code as very suspicious and likely should be removed.

When in doubt ask.

Frederick

TristanKoeln

@fcwilt I removed all G92, and relevled everything, still not working

; homeall.g
; called to home all axes
;
; generated by RepRapFirmware Configuration Tool v3.2.1 on Mon Jan 18 2021 17:44:49 GMT+0100 (Mitteleuropäische Normalzeit)

;DUAL Z 
;M584 Z2:4   

M280 P0 S90
G91                     ; relative positioning
G1 H2 Z10 F6000         ; lift Z relative to current position
G1 H1 X-405 Y-405 F5000 ; move quickly to X and Y axis endstops and stop there (first pass)
G1 H2 X5 Y5 F6000       ; go back a few mm
G1 H1 X-405 Y-405 F360  ; move slowly to X and Y axis endstops once more (second pass)
M98 Phomez.g            ; move Z down stopping at the endstop
G90                     ; absolute positioning
; 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

; homez.g
; called to home the Z axis
;
; generated by RepRapFirmware Configuration Tool v3.2.1 on Mon Jan 18 2021 17:44:49 GMT+0100 (Mitteleuropäische Normalzeit)
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
          ;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

fcwilt

@TristanKoeln

Hi,

After you do a Home ALL or a Home Z what does the DWC report for the Z position?

At the point if you use the Z jog controls to lower the nozzle to just touch the bed what does the DWC report for the Z position?

Thanks.

Frederick

TristanKoeln

@fcwilt after homeing 8,98
nozzel on bead 0,13

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt after homeing 8,98
nozzel on bead 0,13

That suggests that the Z trigger height setting needs to be increased by 0,13.

Frederick

TristanKoeln

@fcwilt oke but that does not close the gabe of about1-2mm

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt oke but that does not close the gabe of about1-2mm

When does this gap of 1-2mm occur?

Frederick

TristanKoeln

@fcwilt when im trying to print

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt when im trying to print

That suggests that something is occurring at the start of a print to cause the gap.

What commands are executed at the start of a print?

Are these commands entered into your slicer or are they in a gcode file on your printer?

Thanks.

Frederick

TristanKoeln

@fcwilt

im using cura with that start code

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt

im using cura with that start code

Thanks.

As a test try starting a print (it doesn't have to finish) but comment out those two commands - the M98 and the G29.

Frederick

TristanKoeln

@fcwilt with no high map loaded the heat is just crushing in the build plate, i stoped the print directly

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt with no high map loaded the heat is just crushing in the build plate, i stoped the print directly

Interesting. That should not happen.

Can you post a screen shot of what your height map looks like in the DWC height map viewer?

Thanks.

Frederick

fcwilt

@fcwilt said in Heigh error after calibrating:

That suggests that the Z trigger height setting needs to be increased by 0,13.

I made a foolish mistake when I posted this:

That suggests that the Z trigger height setting needs to be increased by 0,13.

I typed increased but it should have been decreased.

My apologies.

Frederick

TristanKoeln

@fcwilt

i relvled it before the last test

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt

i relvled it before the last test

Thanks.

When you see the height map far from the grid (up or down) that indicates that the Z=0 datum was not set when the height map was created or the Z trigger height was incorrect.

You can speed the process of creating height maps for testing to determine why they are far from the grid by specifying a 3-by-3 grid in M557 - something like M557 Xaaa:bbb Yccc:ddd P3:3 where aaa,bbb,ccc,ddd are appropriate for your printer.

You wont get any detail but you will get an overall view of the height map to see if some part of it is on the grid.

Frederick

TristanKoeln

@fcwilt what do i have to change to corrwct the z=0 datum

fcwilt

@TristanKoeln said in Heigh error after calibrating:

@fcwilt what do i have to change to corrwct the z=0 datum

Remember when I asked you to post the Z position after G30 and then asked you to jog down to the bed?

And I told you (wrongly) to increase the Z trigger height by 0,13?

If you have not already done so decrease the Z trigger height by 0,13 and perform that test again - home Z and then jog down till nozzle is just touching the bed.

If the Z position when just touching the bed is not 0 adjust the Z trigger height and perform the test again.

If the Z position when just touching the bed is greater than 0 decrease the Z trigger height by that amount and perform the test again.

If the Z position when just touching the bed is less than 0 increase the Z trigger height by that amount and perform the test again.

Once you get the Z position when just touching the bed to be 0 then you have found the correct Z trigger height.

Then you can temporarily change your M557 to create that 3-by-3 height map, create the height map and check the relation of the height map to the grid.

The goal is to determine why that height map is currently so far above the grid.

This is what a perfect height map would look like if it were possible to achieve perfection:

Perfect Height Map.png

Frederick