Homing sets cordinate to 0, but doesn't move (X-axis) - Ideas?

  • Hello,

    I've been building my 300x300 D-Bot for the past few months, and have gotten everything wired and have started configuring the printer. Lots of great comments and the wiki have been a good start, but this being my first custom build (I have an Original Prusa i3 MK1), this has been quite a learning experience.

    I've used the RRF configurator to create my config.g, and home files.

    My current situation is that when I use the webconsole to move X, Y, Z in increments of 10, 1, etc. Everything seems to move in the right direction and distance.

    When I click the "Home X" button on the console, the bed drops a bit (i.e raising the head), and the carriage just sits in place and the X coordinate on the webconsole zero's out. Wherever the head is located at the time, that appears to be the new "zero", and further attempts to move the head along X in a negative direction result in no movement. Moving the head along X in the positive direction works.

    From reading, it seems like when "home X" is hit on the webconsole, it should run the carriage up to -295 and stop when it hits the endstop, but that doesn't appear to be the case.

    NOTE: in the spirit of full disclosure, this the start of my configuration work, so there could very well be a multitude of other error / poor configs in these files that I haven't uncovered - especially around motor configs, acceleration, etc. This detail of configuration is very much a new experience for me.

    Some of the basics for the build:

    • DuetWiFi board - upgraded to 1.19 firmware

    • 17HS19-2004S1 Stepper Motors - Step Angle 1.8 / amp 2.0 / voltage 2.8

    • Makerbot Mechanical end stops - X, Y, Z

    • No Z probe for Bed

    • Mechanical end stop LEDs do light up as well as LEDs on Duet Board when manually triggered


    ; Configuration file for Duet WiFi (firmware version 1.17)
    ; executed by the firmware on start-up
    ; generated by RepRapFirmware Configuration Tool on Sat Sep 30 2017 14:35:37 GMT-0500 (Central Standard Time)

    ; General preferences
    M111 S0 ; Debugging off
    G21 ; Work in millimetres
    G90 ; Send absolute coordinates…
    M83 ; ...but relative extruder moves
    M555 P2 ; Set firmware compatibility to look like Marlin

    M667 S1 ; Select CoreXY mode
    M208 X0 Y0 Z0 S1 ; Set axis minima
    M208 X290 Y290 Z290 S0 ; Set axis maxima

    ; Endstops
    M574 X1 Y2 Z1 S1 ; Define active high microswitches
    M558 P0 X0 Y0 Z0 H5 F120 T6000 ; Set Z probe type to switch, the axes for which it is used and the probe + travel speeds
    G31 P600 X0 Y0 Z2.5 ; Set Z probe trigger value, offset and trigger height
    M557 X15:265 Y15:265 S20 ; Define mesh grid

    ; Drives
    M569 P0 S1 ; Drive 0 goes forwards
    M569 P1 S1 ; Drive 1 goes forwards
    M569 P2 S1 ; Drive 2 goes forwards
    M569 P3 S1 ; Drive 3 goes forwards
    M350 X16 Y16 Z16 E256 I0 ; Configure microstepping without interpolation
    M92 X80 Y80 Z4000 E420 ; Set steps per mm
    M566 X900 Y900 Z12 E120 ; Set maximum instantaneous speed changes (mm/min)
    M203 X900000 Y900000 Z180 E90000 ; Set maximum speeds (mm/min)
    M201 X1500 Y1500 Z250 E4000 ; Set accelerations (mm/s^2)
    M906 X800 Y800 Z800 E800 I30 ; Set motor currents (mA) and motor idle factor in per cent
    M84 S30 ; Set idle timeout

    ; Heaters
    M143 S260 ; Set maximum heater temperature to 260C
    M140 H-1 ; Disable heated bed
    M305 P1 T100000 B4138 C0 R4700 ; Set thermistor + ADC parameters for heater 1

    ; Tools
    M563 P0 D0 H1 ; 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

    ; Fans
    M106 P0 S0.3 I0 F500 H-1 ; Set fan 0 value, PWM signal inversion and frequency. Thermostatic control is turned off
    M106 P1 S1 I0 F500 H1 T45 ; Set fan 1 value, PWM signal inversion and frequency. Thermostatic control is turned on
    M106 P2 S1 I0 F500 H1 T45 ; Set fan 2 value, PWM signal inversion and frequency. Thermostatic control is turned on

    ; Custom settings are not configured

    ; Miscellaneous
    T0 ; Select first tool

    ; homex.g
    ; called to home the X axis
    ; generated by RepRapFirmware Configuration Tool on Sat Sep 30 2017 14:35:37 GMT-0500 (Central Standard Time)

    ; Lift Z relative to current position
    G1 Z5 F6000

    ; Move quickly to X axis endstop and stop there (first pass)
    G1 X-295 F1800 S1

    ; Go back a few mm
    G1 X5 F6000

    ; Move slowly to X axis endstop once more (second pass)
    G1 X-295 F360 S1

    ; Lower Z again
    G1 Z-5 F6000

  • administrators

    You have declared active high microswitches, but I suspect that your 3-wire mechanical endstops provide an active low output. Try changing S1 in the M574 command to S0.

  • Run M119, does it show the X endstop being triggered?

  • Bingo! S0 was the solution.

    Thanks for such a speedy reply!

    Now on to the next DuetWiFi adventure. The Z axis works like the others, but I think I need to do some more research on the offset and how to set that one up correctly, since on the first attempt to home it, the bed collided with the hotend and the front of the bed raised up a bit.

  • administrators


Looks like your connection to Duet3D was lost, please wait while we try to reconnect.