Duet3D Logo Duet3D
    • Tags
    • Documentation
    • Order
    • Register
    • Login

    Y Endstop False Triggers?

    Scheduled Pinned Locked Moved
    Tuning and tweaking
    3
    7
    1.2k
    Loading More Posts
    • Oldest to Newest
    • Newest to Oldest
    • Most Votes
    Reply
    • Reply as topic
    Log in to reply
    This topic has been deleted. Only users with topic management privileges can see it.
    • saffiundefined
      saffi
      last edited by saffi

      So I have this strange glitch with my Y Endstop homing not always working. Copied and pasted below is my homey.g file (350mm Y-axis)

      G91 ; relative mode
      G1 Z2 F1800 ; raise head to avoid dragging nozzle over the bed
      G1 Y-355 F3000 S1 ; move up to 240mm in the -Y direction, stopping if the homing switch is triggered
      G1 Y3 F600 ; move slowly 4mm in the +Y direction
      G1 Y-10 S1 ; move slowly 10mm in the -Y direction, stopping at the homing switch
      G1 Z-2 F1800 ; lower the head again
      G90 ; back to absolute mode

      If the bed is already close to the Y endstop, it homes fine, but if it's finished a print or moved too far away, it moves back slightly and acts like it's triggering the endstop when it is not near home.

      My endstop is attached under the bed and the thermistor, bed heat, and endstop wiring runs together. Could there be some kind of interference causing a false trigger?

      I've been disabling the motors, pushing the bed all the way to the home position where the switch triggers and then re-homing it (which does work). I can play with settings more if anyone has suggestions.

      Update / Edit: I did this strange homey.g check using G92 to fake set Y350 and then move it back to home without relative positioning, but the false endstop trigger (or whatever seems to be happening) did the same or a similar thing.

      Prusa i3 Style Printer with Duet WiFi, E3D Volcano, Bondtech BMG

      1 Reply Last reply Reply Quote 0
      • number40fanundefined
        number40fan
        last edited by number40fan

        Maybe your steps/mm on the Y are off and it isn't moving far enough. Try changing your second G1 to Y-400 or more and see what happens. If it works, make sure the steps are correct or the possibility that you have more travel than you think.

        One last thing would be to make sure there isn't any binding and you have the current turned up enough in your config.g.

        1 Reply Last reply Reply Quote 0
        • dc42undefined
          dc42 administrators
          last edited by

          What type of Y endstop switch are you using? If it is a microswitch, are you using the NC or the NO contacts?

          Duet WiFi hardware designer and firmware engineer
          Please do not ask me for Duet support via PM or email, use the forum
          http://www.escher3d.com, https://miscsolutions.wordpress.com

          1 Reply Last reply Reply Quote 0
          • saffiundefined
            saffi
            last edited by

            @dc42 said in Y Endstop False Triggers?:

            What type of Y endstop switch are you using? If it is a microswitch, are you using the NC or the NO contacts?

            I had an engineer build this printer, so I had to look at the switches up close and it looks like X Axis and Y Axis are both NC. I could pretty easily rewire to NO if that is recommended. The Y Axis switch is using blade terminal clamps (? guessing at the name here), so I may look at that as well, it could need a bit of solder on the actual switch.

            Is the default recommendation for NC or NO switch wiring?

            Prusa i3 Style Printer with Duet WiFi, E3D Volcano, Bondtech BMG

            1 Reply Last reply Reply Quote 0
            • dc42undefined
              dc42 administrators
              last edited by

              The recommendation is to use NC. If the endstop wires run parallel to the stepper motor wires for an appreciable distance, then either or both sets of wires should be twisted pair so that they pick up less interference.

              Have you checked that when you command 10mm of Y movement, you get 10mm? If not then your steps/mm may be incorrect as @number40fan suggested.

              Duet WiFi hardware designer and firmware engineer
              Please do not ask me for Duet support via PM or email, use the forum
              http://www.escher3d.com, https://miscsolutions.wordpress.com

              1 Reply Last reply Reply Quote 0
              • saffiundefined
                saffi
                last edited by

                I'm thinking it must be interference. It seems to randomly trigger within ~1-2 seconds of the bed moving, but if it's close enough to the homing position, it homes in under a second and is fine.

                The switch is fixed to the bottom of the moving bed now, so I may separate it out and place it on the printer body and have it fixed so the bed bumps into the stationary switch.

                Thank you for the help, this forum is a lifeline for printer tinkering.

                Prusa i3 Style Printer with Duet WiFi, E3D Volcano, Bondtech BMG

                dc42undefined 1 Reply Last reply Reply Quote 0
                • dc42undefined
                  dc42 administrators @saffi
                  last edited by

                  @saffi said in Y Endstop False Triggers?:

                  The switch is fixed to the bottom of the moving bed now

                  Could it be a dodgy connection to the switch which sometimes breaks as the wire flexes?

                  Duet WiFi hardware designer and firmware engineer
                  Please do not ask me for Duet support via PM or email, use the forum
                  http://www.escher3d.com, https://miscsolutions.wordpress.com

                  1 Reply Last reply Reply Quote 0
                  • First post
                    Last post
                  Unless otherwise noted, all forum content is licensed under CC-BY-SA