Dual Z Motors single Z Probe as end stop for each motor



  • I've got my dual z motors working.

    ; bed.g
    ; called to perform automatic bed compensation via G32
    ;
    ; Setup for bed levelling using multiple independent Z motors
    
    G28 ; Home
    G30 P0 X0   Y100 Z-99999 ; Z probe Left side lead screw
    G30 P1 X255 Y100 Z-99999 ; Z probe Right side lead screw
    

    and edited config.g

    ; Configuration file for Duet 3 (firmware version 3)
    ; executed by the firmware on start-up
    ;
    ; generated by RepRapFirmware Configuration Tool v3.1.4 on Mon Oct 26 2020 16:22:11 GMT+0000 (Greenwich Mean Time)
    
    ; General preferences
    G90                                                    ; send absolute coordinates...
    M83                                                    ; ...but relative extruder moves
    M550 P"Duet 3"                                         ; set printer name
    
    ; Drives
    M569 P0.0 S1                                           ; physical drive 0.0 goes forwards
    M569 P0.1 S0                                           ; physical drive 0.1 goes backwards
    M569 P0.2 S0                                           ; physical drive 0.2 goes backwards
    M569 P0.3 S0                                           ; physical drive 0.3 goes backwards
    M569 P0.4 S1                                           ; physical drive 0.4 goes forwards
    M569 P0.5 S0                                           ; physical drive 0.5 goes backwards
    M584 X0.0 Y0.1 Z0.2:03 E0.4:0.5                        ; set drive mapping X,Y,Z0,Z1,E0,E1
    M350 X16 Y16 Z16:16 E16:16 I1                          ; configure microstepping with interpolation
    M92 X160.00 Y360.00 Z800.00:800.00 E304.00:304.00      ; set steps per mm
    M566 X900.00 Y900.00 Z60.00:60.00 E120.00:120.00       ; set maximum instantaneous speed changes (mm/min)
    M203 X9000.00 Y9000.00 Z600.00:600.00 E4500.00:4500.00 ; set maximum speeds (mm/min)
    M201 X800.00 Y800.00 Z20.00:20.00 E1000.00:100.00      ; set accelerations (mm/s^2)
    M906 X1360 Y1600 Z1344:1344 E1360:1360 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 X260 Y240 Z280 S0                                 ; set axis maxima
    
    ; Endstops
    M574 X1 S1 P"io1.in"                                   ; configure active-high endstop for low end on X via pin io1.in
    M574 Y1 S1 P"io2.in"                                   ; configure active-high endstop for low end on Y via pin io2.in
    M574 Z1 S2                                             ; configure Z-probe endstop for low end on Z
    
    ; Z-Probe
    M558 P1 C"io3.in" H5 F120 T6000                        ; set Z probe type to unmodulated and the dive height + speeds
    G31 P500 X0 Y0 Z1.888                                  ; set Z probe trigger value, offset and trigger height
    M557 X0:240 Y0:160 S40                                 ; define mesh grid
    
    ; Heaters
    M308 S0 P"temp0" Y"thermistor" T100000 B4267           ; configure sensor 0 as thermistor on pin temp0
    M950 H0 C"out0" T0                                     ; create bed heater output on out0 and map it to sensor 0
    M307 H0 B0 S1.00                                       ; disable bang-bang mode for the bed heater and set PWM limit
    M140 H0                                                ; map heated bed to heater 0
    M143 H0 S120                                           ; set temperature limit for heater 0 to 120C
    M308 S1 P"spi.cs0" Y"rtd-max31865"                     ; configure sensor 1 as thermocouple via CS pin spi.cs0
    M950 H1 C"out1" T1                                     ; create nozzle heater output on out1 and map it to sensor 1
    M307 H1 B0 S1.00                                       ; disable bang-bang mode for heater  and set PWM limit
    M308 S2 P"spi.cs1" Y"rtd-max31865"                     ; configure sensor 2 as thermocouple via CS pin spi.cs1
    M950 H2 C"out2" T2                                     ; create nozzle heater output on out2 and map it to sensor 2
    M307 H2 B0 S1.00                                       ; disable bang-bang mode for heater  and set PWM limit
    
    ; Fans
    M950 F0 C"out7" Q500                                   ; create fan 0 on pin out7 and set its frequency
    M106 P0 S1 H-1                                         ; set fan 0 value. Thermostatic control is turned off
    M950 F1 C"out8" Q500                                   ; create fan 1 on pin out8 and set its frequency
    M106 P1 S1 H-1                                         ; set fan 1 value. Thermostatic control is turned off
    M950 F2 C"out4" Q500                                   ; create fan 2 on pin out4 and set its frequency
    M106 P2 S1 H1 T45                                      ; set fan 2 value. Thermostatic control is turned on
    M950 F3 C"out5" Q500                                   ; create fan 3 on pin out5 and set its frequency
    M106 P3 S1 H2 T45                                      ; set fan 3 value. Thermostatic control is turned on
    M950 F4 C"out9" Q65535                                 ; create fan 4 on pin out9 and set its frequency
    M106 P4 S1 H1:2 T45                                    ; set fan 4 value. Thermostatic control is turned on
    
    ; Tools
    M563 P0 S"Left Extruder" 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
    M563 P1 S"Right Extruder" D1 H2 F1                     ; define tool 1
    G10 P1 X0 Y0 Z0                                        ; set tool 1 axis offsets
    G10 P1 R0 S0                                           ; set initial tool 1 active and standby temperatures to 0C
    
    ; Custom settings
    
    M671 X-35:335 Y100:100                                 ; Define positions of Z Axis lead screws
    
    M307 H0 A233.6 C1178.2 D0.5 V24.1 B0                   ; Heated Bed Calibration 26/10/20
    M307 H1 A327.8 C161.2 D2.8 V24.2 B0                    ; Left Extruder Heater Calibration 17/10/20
    M307 H2 A325.8 C160.8 D3.4 V24.2 B0                    ; Right Extruder Heater Calibration 17/10/20
    
    M106 P0 S0                                             ; Turn Fan 0 OFF
    M106 P1 S0                                             ; Turn Fan 1 OFF
    
    ; Miscellaneous
    M575 P1 S1 B57600                                      ; enable support for PanelDue
    T0                                                     ; select first tool
    

    When I issue a G32 the code in bed.g is executed and detects the two points and calculates the appropriate offsets.

    I would like it level the bed instead ie use the Z probe as an endstop twice and move it the homez.g, then I can use the various meshs for the bed. Is this possible?



  • @Bluemalu said in Dual Z Motors single Z Probe as end stop for each motor:

    I would like it level the bed instead ie use the Z probe as an endstop twice and move it the homez.g, then I can use the various meshs for the bed. Is this possible?

    i dont unserstand what you mean, but your bed.g is incorrect
    its missing the S2
    see
    https://duet3d.dozuki.com/Wiki/Bed_levelling_using_multiple_independent_Z_motors



  • @Veti Thanks for that spot, I'd missed the S2 to calculate the new plane.

    Ignore my question, I've just written it down in a different way and have seen what I am asking is impossible or at least potentially dangerous given the bed is one piece and the steppers don't have a feedback position (think I've played with servo motors for too long).

    I suppose my question should be can you carry out the dual probe and then carry out a mesh calibration or is it pointless?



  • @Bluemalu said in Dual Z Motors single Z Probe as end stop for each motor:

    I suppose my question should be can you carry out the dual probe and then carry out a mesh calibration or is it pointless?

    it depends on the quality of your bed. if your bed is very flat then its pointless.
    if your bed is not flat but does not deform because has a high with, then you can just reload the mesh without probing again.
    otherwise its a good idea to do a G29 after the G32.



  • Perfect, bed is a piece of 6mm tooling aluminium with little flex so no point in over egging the pudding.

    Time to start printing as that was my last query from my upgrade.


Log in to reply