Height Map shifted downwards
-
Hello, lovely members of this forum,
I have a very strange behavior when creating a height map (G29 S0):
The whole map is shifted downwards by around 0.6mm.
Why is this the case?
In my understanding, the point where z=0 is taken should be the point of the height map that is at 0. Why is none of the points at 0?
My homing and config files are normal:
; homeall.g ; called to home all axes ; ; generated by RepRapFirmware Configuration Tool v3.3.12 on Tue Aug 09 2022 15:55:52 GMT+0200 (Mitteleuropäische Sommerzeit) M402 G91 ; relative positioning G1 H2 Z3 F18000 ; lift Z relative to current position G1 H1 X-350 Y-310 F12000 ; move quickly to X or Y endstop and stop there (first pass) G1 H1 X-350 ; home X axis G1 H1 Y-310 ; home Y axis G1 X5 Y5 F18000 ; go back a few mm G1 H1 X-350 F1800 ; move slowly to X axis endstop once more (second pass) G1 H1 Y-310 ; then move slowly to Y axis endstop G90 ; absolute positioning G1 X162 Y152 F18000 ; go to first bed probe point and home Z G30 ; home Z by probing the bed ; Uncomment the following lines to lift Z after probing ;G91 ; relative positioning ;G1 Z3 F300 ; lift Z relative to current position ;G90 ; absolute positioning; Configuration file for Duet WiFi (firmware version 3.3) ; executed by the firmware on start-up ; ; generated by RepRapFirmware Configuration Tool v3.3.12 on Tue Aug 09 2022 15:55:52 GMT+0200 (Mitteleuropäische Sommerzeit) ; General preferences M575 P1 S1 B57600 ; enable support for PanelDue G90 ; send absolute coordinates... M83 ; ...but relative extruder moves M550 P"HCEvo" ; set printer name M669 K1 ; select CoreXY mode ; Drives M569 P0 S0 ; physical drive 0 goes forwards M569 P1 S0 ; physical drive 1 goes forwards M569 P2 S1 ; physical drive 2 goes forwards M569 P3 S0 ; physical drive 3 goes forwards M584 X0 Y1 Z2:4 E3 ; set drive mapping M350 X16 Y16 Z16 E16 I1 ; configure microstepping with interpolation M92 X160.00 Y160.00 Z800.00 E420.00 ; set steps per mm M566 X900.00 Y900.00 Z60.00 E1200.00 ; set maximum instantaneous speed changes (mm/min) M203 X18000.00 Y18000.00 Z1800.00 E8000.00 ; set maximum speeds (mm/min) M201 X5000.00 Y5000.00 Z20.00 E4000.00 ; set accelerations (mm/s^2) M906 X1000 Y1000 Z800 E1000 I30 ; set motor currents (mA) and motor idle factor in per cent M84 S30 ; Set idle timeout ; Axis Limits M208 X0 Y0 Z0 S1 ; set axis minima M208 X345 Y305 Z290 S0 ; set axis maxima ; Endstops M574 X1 S1 P"xstop" ; configure switch-type (e.g. microswitch) endstop for low end on X via pin xstop M574 Y1 S1 P"ystop" ; configure switch-type (e.g. microswitch) endstop for low end on Y via pin ystop M574 Z1 S2 ; configure Z-probe endstop for low end on Z ; Z-Probe M950 S0 C"exp.heater3" ; create servo pin 0 for BLTouch M558 P9 C"^zprobe.in" H3 F180 T18000 ; set Z probe type to bltouch and the dive height + speeds G31 P500 X28 Y9 Z0.5 ; set Z probe trigger value, offset and trigger height M557 X28:328 Y9:309 P2 ; define mesh grid ; Heaters M308 S0 P"e1temp" Y"thermistor" T105526 B4138 ; configure sensor 0 as thermistor on pin e1temp (bedtemp BROKEN) M950 H0 C"bedheat" T0 ; create bed heater output on bedheat and map it to sensor 0 M140 H0 ; map heated bed to heater 0 M143 H0 S120 ; set temperature limit for heater 0 to 120C M308 S1 P"e0temp" Y"thermistor" T103901 B4138 ; configure sensor 1 as thermistor on pin e0temp M950 H1 C"e0heat" T1 ; create nozzle heater output on e0heat and map it to sensor 1 M143 H1 S280 ; set temperature limit for heater 1 to 280C M307 H1 R10.976 K0.652:0.000 D2.65 E1.35 S0.30 B0 V24.0 ; Fans M950 F0 C"fan0" Q500 ; create fan 0 on pin fan0 and set its frequency M106 P0 S0 H-1 ; set fan 0 value. Thermostatic control is turned off M950 F1 C"fan1" Q500 ; create fan 1 on pin fan1 and set its frequency M106 P1 S1 H1 T120 ; set fan 1 value. Thermostatic control is turned on ; Tools M563 P0 D0 H1 F0 ; define tool 0 G10 P0 X0 Y0 Z0 ; set tool 0 axis offsets G10 P0 R0 S0 ; set initial tool 0 active and standby temperatures to 0C ; Custom settings are not defined ; Miscellaneous M911 S10 R11 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000" ; set voltage thresholds and actions to run on power loss M572 D0 S0.38 ;0.64 fuer 0.4mm Nozzle -
@Tryptamine This usually happens because Z is not homed, or is homed with an incorrect offset, or if the Z is moved after homing and reset to Z0. I can see you are using a BLTouch to home Z in homeall.g. The Z offset is very small at 0.5mm, though. Do you do anything else before sending G29 S0? Do you have a sys/mesh.g file? Please also post what firmware version you're using.
Ian
-
Please keep it to a single topic
https://forum.duet3d.com/topic/30594/significant-z-offset-of-bed-mesh?_=1670008389610
