Nozzle to high when printing BLTouch

jasko

Hi,

I have issue that when I do z probe in home all when i go to G1 Z0 nozzle is 1mm away from build plate, so when print starts it is 1mm higher than it should have. I have done Z probe calibration many times. Mesh bed compensation also. Baby stepping does not work also I put even -0.5 but nothing happens, but it triggers some error that printer is out of limits... Any advice would be great. I am using latest beta firmware.

homeall.g config.g

Veti

if you know that its off by 1mm increase the G31 z offset by 1mm

jasko

Tried that but noting happens, its like this offset is ignored.

Veti

@jasko

maybe you set the offset accidentally in
M558

M558 P9 X0 Y0 Z0.5 H5 F120 T6000 ; Set Z Probe to type Switch or Digital output where Z probe connector is used. Used for z only.

x y z should not be part of the M558 command

also you should adjust your config properly for dual y setup.
see
https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors#Section_In_RepRapFirmware_Num_3

M574 Z2 S1 P"io4.in" ; configure active-high endstop for high end on Z via pin io4.in

are you really using a z endstop switch?

G1 H1 X-10 Y-10 u-10 F360 ; move slowly to X and Y axis endstops once more (second pass)
G92 Y0 ;set current position of y axis to 0

dont do the G92 Y0 in homing

DIY-O-Sphere

At the end of your config you read the stored values. (M501)
Please check config-override.g

jasko

@Veti said in Nozzle to high when printing BLTouch:

M574 Z2 S1 P"io4.in" ; configure active-high endstop for high end on Z via pin io4.in

I have removed it but nothing changes.

I'll make those changes for y axis for now it works.

Should I eliminate z endstop switch? Can i use it for homing but instead of z probe homing? But I would still like to use mesh bed compensation?

jasko

@DIY-O-Sphere Those are for headed bed, PID tuning.

Veti

post the output of G31 send in the console

jasko

This is result of G31:

Z probe 0: current reading 0, threshold 500, trigger height 0.700, offsets X0.0 Y0.0

This is from config.g:

G31 P25 X-38.2 Y-11 Z1.447							   ; Set Z probe trigger value, offset and trigger height

Phaedrux

M558 P9 X0 Y0 Z0.5 H5 F120 T6000                     ; Set Z Probe to type Switch or Digital output where Z probe connector is used. Used for z only.
G31 P25 X-38.2 Y-11 Z1.447								; Set Z probe trigger value, offset and trigger height

; Z-Probe
M950 S0 C"io7.out"                                  ; disable heater on PWM channel for BLTouch
M558 P9 C"io7.in" H5 F100 T3000                     ; disable Z probe but set dive height, probe speed and travel speed
M557 X50:840 Y50:1050 S100                         ;defining mesh probe grid

The order of these commands is the problem. You have two instances of M558 and the G31 must come after M558.

Change it to this:

; Z-Probe
M950 S0 C"io7.out"                                  ; disable heater on PWM channel for BLTouch
M558 P9 C"io7.in" H5 F100 T3000                     ; disable Z probe but set dive height, probe speed and travel speed
G31 P25 X-38.2 Y-11 Z1.447								; Set Z probe trigger value, offset and trigger height
M557 X50:840 Y50:1050 S100                         ;defining mesh probe grid

jasko

@Phaedrux Thank you this worked.