z motors drives faster than the should

  • Hey everybody,

    I have a little problem with my 4 z motors. When I would like to home the z motors, they drive up very loud, than x and y home normally and when the z motors drives down, i think they would be to fast. 2 z motors don't go further, blocking and making loude noise.

    I'm using external stepper drivers (leadshine DM556) for the z motors with Expansion Breakout Board.

    I think, I have set the stepper driver right.

    Here you have two pictures.


    Motor data sheed
    Screenshot (28).png

    leadshine DM556 datasheet


    ; Configuration file for Duet WiFi (firmware version 3)
    ; executed by the firmware on start-up
    ; generated by RepRapFirmware Configuration Tool v3.1.4 on Tue Sep 29 2020 15:16:53 GMT+0200 (Mitteleuropäische Sommerzeit)
    ; General preferences
    G90                                                                  ; send absolute coordinates...
    M83                                                                  ; ...but relative extruder moves
    M550 P"3D Printer"                                                      ; set printer name
    ; Network
    M551 P"****"                                                       ; set password
    M552 S1                                                              ; enable network
    M586 P0 S1                                                           ; enable HTTP
    M586 P1 S0                                                           ; disable FTP
    M586 P2 S0                                                           ; disable Telnet
    ; Drives
    M569 P0 S1                                                            ; physical drive 0 goes forwards
    M569 P1 S1                                                            ; physical drive 1 goes forwards
    M569 P5 S1 R1 T2.5:2.5:5:0                                            ; physical drive 5 goes forwards
    M569 P3 S1                                                            ; physical drive 3 goes forwards
    M569 P4 S1                                                            ; physical drive 4 goes forwards
    M569 P6 S1 R1 T2.5:2.5:5:0                                            ; physical drive 6 goes forwards
    M569 P7 S1 R1 T2.5:2.5:5:0                                            ; physical drive 7 goes forwards
    M569 P8 S1 R1 T2.5:2.5:5:0                                                           ; physical drive 8 goes forwards
    M584 X0 Y1:4 Z5:6:7:8 E3                                             ; set drive mapping
    M350 Y256:256 Z4:4:4:4 I0                                            ; configure microstepping without interpolation
    M350 X16 E16 I1                                                      ; configure microstepping with interpolation
    M92 X448.00 Y241.37:241.37 Z1280.00:1280.00:1280.00:1280.00 E420.00  ; set steps per mm
    M566 X900.00 Y900.00:900.00 Z12.00:12.00:12.00:12.00 E120.00         ; set maximum instantaneous speed changes (mm/min)
    M203 X6000.00 Y6000.00:6000.00 Z180.00:180.00:180.00:180.00 E1200.00 ; set maximum speeds (mm/min)
    M201 X500.00 Y500.00:500.00 Z20.00:20.00:20.00:20.00 E250.00         ; set accelerations (mm/s^2)
    M906 X1800 Y1800:1800 Z800:800:800:800 E800 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 X1280 Y2500 Z1500 S0                                            ; set axis maxima
    ; Endstops
    M574 X1 S1 P"!xstop"                                                 ; configure active-high endstop for low end on X via pin !xstop
    M574 Y2 S1 P"!ystop"                                                 ; configure active-high endstop for high end on Y via pin !ystop
    M574 Z1 S2                                                           ; configure Z-probe endstop for low end on Z
    ; Z-Probe
    M950 S0 C"duex.pwm5"                                                 ; create servo pin 0 for BLTouch
    M558 P9 C"^zprobe.in" H5 F120 T6000                                  ; set Z probe type to bltouch and the dive height + speeds
    G31 P500 X0 Y0 Z2.5                                                  ; set Z probe trigger value, offset and trigger height
    M557 X15:1265 Y15:2485 S20                                           ; define mesh grid
    ; Heaters
    M308 S0 P"bedtemp" Y"thermistor" T100000 B4138                       ; configure sensor 0 as thermistor on pin bedtemp
    M950 H0 C"bedheat" T0                                                ; create bed heater output on bedheat and map it to sensor 0
    M307 H0 B1 S1.00                                                     ; enable 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.cs1" Y"rtd-max31865"                                   ; configure sensor 1 as thermocouple via CS pin spi.cs1
    M950 H1 C"e0heat" T1                                                 ; create nozzle heater output on e0heat and map it to sensor 1
    M307 H1 B0 S1.00                                                     ; disable bang-bang mode for heater  and set PWM limit
    ; 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
    ; Tools
    M563 P0 S"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
    ; Custom settings are not defined
    ; Miscellaneous
    M575 P1 S1 B57600                                                    ; enable support for PanelDue
    M911 S21 R22 P"M913 X0 Y0 G91 M83 G1 Z3 E-5 F1000"                   ; set voltage thresholds and actions to run on power loss

    I don't find the problem.

    Many thanks for your help!

    Best regards

  • administrators

    You have set your Z steps/mm to 1280 in config.g, however you have set the steps/rev to just 400. That combination implies your leadscrew has a lead (linear movement per turn) of 400/1280 = 0.3125mm. What should it be?

    Steps/rev set to 3200 or 6400 would be more normal.

  • @dc42 you are so right!!!

    I've set the wrong gear ratio.

    Now it's working!!!

    Thank you very much!!!

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