Delta just converted, can't get autocalibrate to work

  • Hello everyone. Normally I google/power my way through problems on my own, but this I just can't quite figure out what I need to do. I kind of killed the junk motherboard in my FLSUN Kossel (basically Anycubic Kossel), and I thought why not use the Duet Wifi 1.0 board I have sitting around which has never been used. I have it printing surprisingly well for no autocalibration, but I know at least with Marlin that improves quality tremendously.

    The "Delta Calibration (G32)" moves to several points in the Z=5.65 plane, but it never actually probes the bed. It seems like it does not think I have a probe.

    This printer has a simple endstop switch in the effector, so when the nozzle pushes on the bed it clicks the switch. I think I have it set right? It is plugged into the E0 Stop and the corresponding ground. Config.g probe lines:

    M558 P4 X0 Y0 Z0 H3 F300 T12000
    G31 X0 Y0 Z0.65 P500

    I also get "No valid grid" for mesh compensation, but I am less worried about that and more worried about delta calibration.

    If it helps, this is my bed.g file:

    ; bed.g file for RepRapFirmware, generated by Escher3D calculator
    ; 10 points, 7 factors, probing radius: 80, probe offset (0, 0)
    G30 P0 X0.00 Y80.00 Z-99999 H0
    G30 P1 X69.28 Y40.00 Z-99999 H0
    G30 P2 X69.28 Y-40.00 Z-99999 H0
    G30 P3 X0.00 Y-80.00 Z-99999 H0
    G30 P4 X-69.28 Y-40.00 Z-99999 H0
    G30 P5 X-69.28 Y40.00 Z-99999 H0
    G30 P6 X0.00 Y40.00 Z-99999 H0
    G30 P7 X34.64 Y-20.00 Z-99999 H0
    G30 P8 X-34.64 Y-20.00 Z-99999 H0
    G30 P9 X0 Y0 Z-99999 S7

    Oh, one last thing, I can't find any way to adjust individual diagonal rod length to correct for one dimension being shorter than the other for 6 sided calibration objects. As far as I can tell, RepRap doesn't have an adjustment for that like Marlin does. Am I stuck with slightly off dimensions?

  • I have found Anycubic Kossel probe switches to be wired "backwards" from what you really want. Check things with an ohmeter. It has been so long I don't remember all the details; I do remember re-soldering the switch. Later went to a smart effector.

    This is a working switch definition and bed.g for an AKL plus:

    ; Z-Probe
    M558 P4 H5 F120 T6000                              ; Set Z probe type to switch and the dive height + speeds
    G31 P1000 X0 Y0 Z20.5                              ; Set Z probe trigger value, offset and trigger height
    M557 R105 S20                                      ; Define mesh grid
    ; bed.g
    ; called to perform automatic delta calibration via G32
    ; generated by RepRapFirmware Configuration Tool on Thu Jul 12 2018 20:54:00 GMT-0500 (Central Daylight Time)
    M561 ; clear any bed transform
    G28  ; home all towers
    ; Probe the bed at 6 peripheral and 3 halfway points, and perform 6-factor auto compensation
    ; Before running this, you should have set up your Z-probe trigger height to suit your build, in the G31 command in config.g.
    G30 P0 X0 Y104.9 H0 Z-99999
    G30 P1 X90.85 Y52.45 H0 Z-99999
    G30 P2 X90.85 Y-52.45 H0 Z-99999
    G30 P3 X0 Y-104.9 H0 Z-99999
    G30 P4 X-90.85 Y-52.45 H0 Z-99999
    G30 P5 X-90.85 Y52.45 H0 Z-99999
    G30 P6 X0 Y52.4 H0 Z-99999
    G30 P7 X45.38 Y-26.2 H0 Z-99999
    G30 P8 X-45.38 Y-26.2 H0 Z-99999
    G30 P9 X0 Y0 H0 Z-99999 S6
    ; Use S-1 for measurements only, without calculations. Use S4 for endstop heights and Z-height only. Use S6 for full 6 factors
    ; If your Z probe has significantly different trigger heights depending on XY position, adjust the H parameters in the G30 commands accordingly. The value of each H parameter should be (trigger height at that XY position) - (trigger height at centre of bed)

  • Thanks for the fast reply! The mesh grid line was exactly what I needed (M557)! I just had to tweak the radius down because I have a smaller bed.

    For the Z probe, I figured out my problem. I was putting the gcode in for REPRAP 2.X, and I'm on 3.0 For anyone that ever comes across this looking for this answer, after plugging into the probe instead of E0, this is the line that made my probe work:

    M558 P5 C"^" H5.0 F120 T6000

    Also, after doing the autocalibration, I figured out how to do individual rod lengths for X/Y/Z, to adjust for slight discrepancies in rod length you just put it in as "L210:210:211" instead of "L210.33", I assume for X Y Z respectively (still testing that).

    Now that I think I have everything figured out, I am really digging my Duet board. To think I almost got a hold of another 8bit noisy marlin board. No more juggling SD cards or dragging a USB cable and compiling every time I want to adjust or print something.

Log in to reply