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

    Firmware Skips a few gcode instructions -- known issue?

    Scheduled Pinned Locked Moved Solved
    CNC
    3
    20
    935
    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.
    • Phaedruxundefined
      Phaedrux Moderator @N7JTI
      last edited by

      @N7JTI said in Firmware Skips a few gcode instructions -- known issue?:

      Is there a version of the CNC specific web interface that is approved/safe for the beta firmware?

      Yes. https://forum.duet3d.com/topic/20416/preview-version-of-cnc-optimized-dwc/36

      @N7JTI said in Firmware Skips a few gcode instructions -- known issue?:

      Probing with my z-probe now appears to be unreliable. It either doesn't probe downward, or probes downward very little. This was very reliable before. I couldn't find any documentation related to changes in this area.

      Would need some more details on your probe.

      I do notice that your configuration for the probe is missing some parameters.

      @N7JTI said in Firmware Skips a few gcode instructions -- known issue?:

      ; Z-Probe
      M558 K0 P5 C"^!io1.in" F120 T6000 ; Z probe speed and travel speed
      G31 Z25.4 ; set the z-probe trigger height to 1 inch

      G31 is missing P for trigger sensitivity and the X Y offset.

      Z-Bot CoreXY Build | Thingiverse Profile

      N7JTIundefined 3 Replies Last reply Reply Quote 0
      • N7JTIundefined
        N7JTI @Phaedrux
        last edited by

        @Phaedrux The z-probe is just a machined touch plate. Basically it acts like a switch, but really it is just measuring current passing through the tool itself into the touch plate. Well, to be brutally specific, the tool is "ground" and the current source is the touch plate. x-y offset should be zero, as the tool itself makes the contact and there is no offset. The z-offset is 1 inch.

        I haven't been able to figure out how to get G30 to do anything like what I need. I've pasted the macro I use to set my z0 below. Should this be possible from a G30 command? How?

        The behavior of this macro seemed to be different with the new firmware. I've had to update my "dive height" with an h-parameter in M558 so that it probes toward the workpiece more than just a handful of mm.

        z_probe.g macro

        ; Probe in Z and reset 0

        G91 ; Set Relative Mode
        G38.2 Z P0 ; probe in the z direction
        G10 L20 P1 Z25.4 ; set the z-height of WCS 1 to 1 inch
        G0 Z50 ; rise up around 25mm to remove the z-plate
        G90 ; Set Absolute Mode

        1 Reply Last reply Reply Quote 0
        • N7JTIundefined
          N7JTI @Phaedrux
          last edited by

          @Phaedrux My recent updates to try and get probing to actually probe down far enough to reliably set zero

          ; Z-Probe
          M558 K0 P5 H20 C"^!io1.in" F120 T6000 ; Z probe speed and travel speed
          G31 X0 Y0 Z25.4 ; set the z-probe trigger height to 1 inch

          1 Reply Last reply Reply Quote 0
          • N7JTIundefined
            N7JTI @Phaedrux
            last edited by

            @Phaedrux 20201230_112942.jpg

            1 Reply Last reply Reply Quote 0
            • Phaedruxundefined
              Phaedrux Moderator
              last edited by

              Try adding P500 to G31 as well

              Does G30 work now?

              I'm not as familiar with g38 for CNC

              https://duet3d.dozuki.com/Wiki/Gcode?revisionid=HEAD#Section_G38_2_to_G38_5_Straight_Probe

              Z-Bot CoreXY Build | Thingiverse Profile

              N7JTIundefined 1 Reply Last reply Reply Quote 0
              • N7JTIundefined
                N7JTI @Phaedrux
                last edited by

                @Phaedrux Well, that just cost me a bit and damaged my touch-pate.

                I ran "g30" and the head dropped carefully down till it touched the plate... and then drove the v-bit straight down into the plate until the motors couldn't drive any further... badly scratching the touch plate and chipping the bit.

                So, what I would like to have seen it do is STOP when it made contact with the touch plate.

                So, how is G30 supposed to work?

                1 Reply Last reply Reply Quote 0
                • Phaedruxundefined
                  Phaedrux Moderator
                  last edited by

                  Well g30 should stop when triggered provided the trigger pin is configured correctly, but I'm not a CNC user at all, so I'm not sue what else could be going on.

                  If the macro you have using G38.2 works as you expect that should be fine.

                  Only thing I can think of is to remove the K0 from M558 since you only have a single probe anyway.

                  Z-Bot CoreXY Build | Thingiverse Profile

                  N7JTIundefined 1 Reply Last reply Reply Quote 0
                  • N7JTIundefined
                    N7JTI @Phaedrux
                    last edited by N7JTI

                    @Phaedrux but the problem I seem to be having with BOTH of these is that the directions are very backwards. instead of lifting on a g30 contact it is diving. And instead of probing DOWN towards the touchplate with the G38 command it is probing UP.

                    Does the beta firmware probing not pay attention to which direction is positive on my z-axis? This used to work.

                    1 Reply Last reply Reply Quote 0
                    • N7JTIundefined
                      N7JTI
                      last edited by

                      Ok, I think I may have found it. The dive height I set negative becase it was probing the wrong direction... that seemed to have unintended consequences. So it is no longer diving after touching the plate.
                      ...

                      Phaedruxundefined 1 Reply Last reply Reply Quote 0
                      • N7JTIundefined
                        N7JTI
                        last edited by

                        Ok, so here's the problem I've got with G30. It probes the bed and sets the machine coordinates.

                        That isn't helpful. I need the WCS coordinates to be updated to z0.

                        1 Reply Last reply Reply Quote 0
                        • Phaedruxundefined
                          Phaedrux Moderator @N7JTI
                          last edited by

                          @N7JTI said in Firmware Skips a few gcode instructions -- known issue?:

                          The dive height I set negative becase it was probing the wrong direction

                          That would do it.

                          @N7JTI said in Firmware Skips a few gcode instructions -- known issue?:

                          That isn't helpful. I need the WCS coordinates to be updated to z0.

                          Ok, so does G38.2 and the macro you have do what you're needing?

                          Z-Bot CoreXY Build | Thingiverse Profile

                          1 Reply Last reply Reply Quote 0
                          • N7JTIundefined
                            N7JTI
                            last edited by

                            Ok, the machine seems to be performing mostly correctly now. I'm still seeing my macro probing the wrong direction occasionally, but I haven't caught it doing that in the last half-our. So I'm going to mark this as "solved" since my problem of the head occasionally not lifting seems to be fixed by the updated firmware.

                            If I can find a clear pattern for when the probing macro probes "towards the workpiece" in the wrong direction I'll open another question.

                            Thanks again for the great support!

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