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

Sensorless homing not going so great

Scheduled Pinned Locked Moved
Tuning and tweaking
2
8
1.5k
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.
  • undefined
    krakert
    last edited by 23 Mar 2018, 10:55

    Hey everybody,

    I Been trying to get the sensorless homing to work good, it got it working for the X axis but the Y axis i cant get to work.

    I am using the same code for the two axis:

    [[language]]
    M400 ; make sure everything has stopped before we make changes
    M913 X50 Y50 ; XY motors to 65% current
    M915 X S1 R0 F0 ; set X and Y to sensitivity 0, do nothing when stall, unfiltered
    M574 X1 Y1 S3 ; set endstops to use motor stall
    G1 S1 X-325 F2400 ; move right/back 325mm, stopping at the endstop
    G4 P500 ; wait 500msec
    G1 X1 ; move away from home
    G4 P500 ; wait 500msec
    M400 ; make sure everything has stopped before we make changes

    https://www.youtube.com/watch?v=qj459IFUCGI&feature=youtu.be

    This is the code for Y axis, they are almost the same, but this axis does not move, only a litte bit

    [[language]]
    M400 ; make sure everything has stopped before we make changes
    M915 Y S50 R0 F0 ; set X and Y to sensitivity 0, do nothing when stall, unfiltered
    M574 X1 Y1 S3 ; set endstops to use motor stall
    G1 S1 Y-325 F2400 ; move right/back 325mm, stopping at the endstop
    G4 P500 ; wait 500msec
    G1 Y1 ; move away from home
    G4 P500 ; wait 500msec
    M400 ; make sure everything has stopped before we make changes

    https://youtu.be/aPMjiQzARCc

    As you can see in the two videos that axis Y just is not moving. Also the Stall detection threshold is very high but that does not changes a thing. Any ideas what I am doing wrong here!?

    1 Reply Last reply Reply Quote 0
    • undefined
      dc42 administrators
      last edited by 23 Mar 2018, 12:27

      Is it a CoreXY machine? If so then a stall on either the X or the Y motor will stop an X or Y homing move. So you need to configure the stall thresholds of both motors with M915.

      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
      • undefined
        krakert
        last edited by 23 Mar 2018, 13:37

        Well after a few hours i made the following code:

        [[language]]
        M400 ; make sure everything has stopped before we make changes
        M574 X2 Y2 S3 ; set endstops to use motor stall
        M913 X50 Y50 ; drop motor currents to 50%
        M915 X Y S2 R0 F0 ; set X and Y to sensitivity 2, do nothing when stall, unfiltered
        G91 ; use relative positioning
        G1 S1 X-500 F3600 ;move right/back 325mm, stopping at the endstop
        G4 P500 ; wait 500msec
        G92 X0 ;
        G1 X5 F200 ;
        M400 ; make sure everything has stopped before we make changes
        M913 X100 Y100 ; drop motor currents to 50%
        M400 ; make sure everything has stopped before we make changes
        M574 X2 Y2 S3 ; set endstops to use motor stall
        M913 X50 Y50 ; drop motor currents to 50%
        M915 X Y S2 R0 F0 ; set X and Y to sensitivity 2, do nothing when stall, unfiltered
        G91 ; use relative positioning
        G1 S1 Y-500 F3600 ;move right/back 325mm, stopping at the endstop
        G4 P500 ; wait 500msec
        G92 Y0 ;
        G1 Y5 F200 ;
        M400 ; make sure everything has stopped before we make changes
        M913 X100 Y100 ; drop motor currents to 50%

        Works great! but I need to use a G92 to set the Axis at 0.0 mm , not sure if that is the best way yet.

        1 Reply Last reply Reply Quote 0
        • undefined
          dc42 administrators
          last edited by 23 Mar 2018, 15:21

          You should not need those G92 commands. What happens without them?

          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
          • undefined
            krakert
            last edited by 23 Mar 2018, 17:24

            Well when the axis are at 200mm and i do the homing. The axis end up at 300mm insteed of 0mm. But maybe it did not works because i was running the code in a macro insteed of the home x and home y files.

            I will try iT without the G92 in the home x and home y files.

            I also have the feeling that the homeall file dus something else than i have typed. The homeall file is just the combined program of the home Y and X file.

            So have Some more thing to find out. But i will het there

            1 Reply Last reply Reply Quote 0
            • undefined
              krakert
              last edited by 24 Mar 2018, 07:05

              I been thinking a bit, but is this possible that the printers is homing to the maximum length of the axis!?

              I have set the maximum length of the axis at 300mm and every time i home the machine the X and Y values are 300mm

              That why I need a G92 in the home cycle.
              But how do I change that!? homing to min!?

              1 Reply Last reply Reply Quote 0
              • undefined
                dc42 administrators
                last edited by 24 Mar 2018, 08:19

                Your M574 commands say that you are homing to high end endstops (X2, Y2) but you are homing to the low end so it should be X1, Y1.

                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
                • undefined
                  krakert
                  last edited by 24 Mar 2018, 16:09

                  @dc42:

                  Your M574 commands say that you are homing to high end endstops (X2, Y2) but you are homing to the low end so it should be X1, Y1.

                  Yes you are right! now homing great, now just getting the Bltouch to work as Z axis homing!

                  1 Reply Last reply Reply Quote 0
                  2 out of 8
                  • First post
                    2/8
                    Last post
                  Unless otherwise noted, all forum content is licensed under CC-BY-SA