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

    Extruder churns extremely fast when printing, but step/mm is correct.

    Scheduled Pinned Locked Moved
    Tuning and tweaking
    7
    18
    3.5k
    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.
    • dintidundefined
      dintid
      last edited by

      @Fickert:

      I have this same problem using cura and craftware. Is there a specific way to eliminate this in the slicer settings?

      Adding M82 in my start gcode seemed to solve it.
      I say "seemed" as my bed didn't bother to go to 0, but that might be totally unrelated… extruder geared down to what seemed the right speed
      https://duet3d.com/wiki/G-code#M82:_Set_extruder_to_absolute_mode

      RepRapFirmware supported G-codes: https://duet3d.com/wiki/G-code

      1 Reply Last reply Reply Quote 0
      • deckingmanundefined
        deckingman
        last edited by

        The default for Duet is relative extrusion. Most people set their slicers to use relative so that it matches. If you choose to use absolute extrusion instead in your slicer, then you need to "tell" the Duet that's what you are doing by using M82 in your config.g. For info, M83 will switch the Duet back to it's default use of relative extrusion.

        Ian
        https://somei3deas.wordpress.com/
        https://www.youtube.com/@deckingman

        1 Reply Last reply Reply Quote 0
        • dintidundefined
          dintid
          last edited by

          @deckingman:

          The default for Duet is relative extrusion. Most people set their slicers to use relative so that it matches. If you choose to use absolute extrusion instead in your slicer, then you need to "tell" the Duet that's what you are doing by using M82 in your config.g. For info, M83 will switch the Duet back to it's default use of relative extrusion.

          I havn't set it to do anything. In fact, I choose to use a vanilla install of Cura 🙂
          I've never had this issue with any Marlin or Smoothieware installation.

          RepRapFirmware supported G-codes: https://duet3d.com/wiki/G-code

          1 Reply Last reply Reply Quote 0
          • deckingmanundefined
            deckingman
            last edited by

            Obviously then Marlin and Smoothieware default to using Absolute extrusion. If you used Slic3R as your slicer, you'd likely find that defaults to using relative. Every slicer and every "brand" of firmware have their own default settings, which is what I meant what I said that you have to "tell" the firmware what you choose to use. (or alternatively "tell" the slicer).

            Ian
            https://somei3deas.wordpress.com/
            https://www.youtube.com/@deckingman

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

              In fact RepRapFirmware defaults to absolute extrusion. But you can change that to relative by putting M83 in your config.g file.

              Most slicers generate either M82 or M83 in the start gcode to tell the printer what they expect. It sounds as though Cura does not.

              Cura is unique amongst the slicers I am familiar with in that it doesn't support relative extrusion, which is a pity because relative extrusion makes more sense and avoids rounding errors.

              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
              • burtoogleundefined
                burtoogle
                last edited by

                I'd need to go check the source to confirm this but I think Cura limits the maximum absolute extrusion value emitted by segmenting (resetting back to 0 every now and again as the print progresses). Perhaps they do that to limit the amount of rounding error accumulated.

                1 Reply Last reply Reply Quote 0
                • Fickertundefined
                  Fickert
                  last edited by

                  This is amazing news! I love using Craftware but had this issue and had no idea why. Very very nice.

                  1 Reply Last reply Reply Quote 0
                  • deckingmanundefined
                    deckingman
                    last edited by

                    @dc42:

                    In fact RepRapFirmware defaults to absolute extrusion. ….......................

                    Oops, sorry. So all the OP needed to do was omit the M83 he must have had in his config.g which was telling Duet to use relative extrusion.

                    Ian
                    https://somei3deas.wordpress.com/
                    https://www.youtube.com/@deckingman

                    1 Reply Last reply Reply Quote 0
                    • burtoogleundefined
                      burtoogle
                      last edited by

                      As I thought, Cura does this…

                      if (getCurrentExtrudedVolume() > 10000.0) //According to https://github.com/Ultimaker/CuraEngine/issues/14 having more then 21m of extrusion causes inaccuracies. So reset it every 10m, just to be sure.
                      {
                      resetExtrusionValue();
                      }

                      ambrop72 created this issue in Ultimaker/CuraEngine

                      closed Absolute extruder coordinates should be reset and not grow unbounded. #14

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

                        Yes most if not all slicers do that when using absolute extrusion to limit the accumulated rounding error.

                        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
                        • dintidundefined
                          dintid
                          last edited by

                          @deckingman:

                          @dc42:

                          In fact RepRapFirmware defaults to absolute extrusion. ….......................

                          Oops, sorry. So all the OP needed to do was omit the M83 he must have had in his config.g which was telling Duet to use relative extrusion.

                          This one keyed me in on what to look for, thanks.

                          Problem is that the Web Configurator put the M83 in there.. not me, meaning the Duet WiFi by all purposes is doing this by default.

                          I'll remove it and see how it behaves.

                          RepRapFirmware supported G-codes: https://duet3d.com/wiki/G-code

                          1 Reply Last reply Reply Quote 0
                          • dintidundefined
                            dintid
                            last edited by

                            That fixed everything 🙂 (removing the M83 the Web Configurator puts in there)

                            RepRapFirmware supported G-codes: https://duet3d.com/wiki/G-code

                            1 Reply Last reply Reply Quote 0
                            • dintidundefined
                              dintid
                              last edited by

                              My machine is actually stil overextruding, but only by a factor 2 and not by 10, so something is still amis.

                              RepRapFirmware supported G-codes: https://duet3d.com/wiki/G-code

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