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    When a print is paused, Z is reduced by 0.03/0.04 mm on restart

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    • jens55undefined
      jens55 @moth4017
      last edited by

      @moth4017, yes, my tools have different offsets but there is no tool change involved. If it is an issue of tool offset, why would the height continue to reduce for every pause cycle?
      I will see what happens when my z offsets are the same.

      moth4017undefined 1 Reply Last reply Reply Quote 0
      • moth4017undefined
        moth4017 @jens55
        last edited by

        @jens55 may be there is an undisclosed design feature (bug) that's taking of the offset from one of the tools , did you try making all the offsets the same ?

        <

        jens55undefined 1 Reply Last reply Reply Quote 0
        • jens55undefined
          jens55 @moth4017
          last edited by

          @moth4017, yes, just finished testing with all the same z offsets. Problem still exists.

          moth4017undefined 1 Reply Last reply Reply Quote 0
          • moth4017undefined
            moth4017 @jens55
            last edited by

            @jens55 can you post your config

            <

            jens55undefined 1 Reply Last reply Reply Quote 0
            • jens55undefined
              jens55 @moth4017
              last edited by

              @moth4017
              config.g

              moth4017undefined 1 Reply Last reply Reply Quote 0
              • moth4017undefined
                moth4017 @jens55
                last edited by

                @jens55 in your config you are doing calculations instead of putting in the value, it may be a rounding issue , you could try putting in fixed values .

                <

                jens55undefined 1 Reply Last reply Reply Quote 0
                • jens55undefined
                  jens55 @moth4017
                  last edited by jens55

                  @moth4017, what in specific are you referring to?
                  Yes, I calculate motor current but that has no bearing on the issue.
                  I calculate z steps but that is an even number (no rounding) and besides, we are not talking actual height error (if the steps per mm are wrong) but we are talking what DWC 'thinks' is the z height.

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                  • jens55undefined
                    jens55
                    last edited by

                    I just looked at the object model during a pause and the Z height is correct. It would appear that the printer goes back to the right position and then reduces Z height somehow. This is confirmed by the DWC Z height display where, during the resume, z height goes to 0.2 (first layer height) and then drops down to 0.16.
                    It sure looks like there is some macro someplace that somehow changes the height on resume .... but where would this happen ... is there something that automatically runs after pause.g has executed ????

                    moth4017undefined 1 Reply Last reply Reply Quote 0
                    • moth4017undefined
                      moth4017 @jens55
                      last edited by

                      @jens55 just a question are you doing the pause from DWC or in the slicer software ? eg pause at height x "do something" then resume?

                      <

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                      • jens55undefined
                        jens55
                        last edited by

                        How does resurrect.g fit in the big picture? I thought it only applies when there was a power outage?
                        The reason I bring this up is because the resurrect.g file contains this line:

                        G92 X266.207 Y126.771 Z-0.036 U0.000

                        and the z-0.036 seems very much like the error I am seeing.

                        moth4017undefined 2 Replies Last reply Reply Quote 0
                        • moth4017undefined
                          moth4017 @jens55
                          last edited by

                          @jens55 Any time you pause a print from SD card, the state of the print is saved to a special file on the SD card, sys/resurrect.g

                          <

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                          • moth4017undefined
                            moth4017 @jens55
                            last edited by

                            @jens55 set value to 0 sys/resurrect.g and test 🙂

                            <

                            jens55undefined 1 Reply Last reply Reply Quote 0
                            • jens55undefined
                              jens55 @moth4017
                              last edited by jens55

                              @moth4017, I need a bit more than that .... resurrect.g has a whole bunch of lines. Are you suggesting to set the Z portion of the G92 line to 0? BTW, on the other two printers the Z portion of the G92 command is 0.2.

                              Also, when I enter M911, the printer reports that auto save is disabled .... why would resurrect.g be run if auto save is disabled?

                              moth4017undefined 1 Reply Last reply Reply Quote 0
                              • moth4017undefined
                                moth4017 @jens55
                                last edited by

                                @jens55 just change this line G92 X266.207 Y126.771 Z0 U0.000

                                you will have to try and work out when it happens

                                you can add the :-

                                echo "this just happened"

                                in the *.g files to give you a pointer to when the move happens. and then monitor it in the DWC console

                                <

                                jens55undefined 1 Reply Last reply Reply Quote 0
                                • jens55undefined
                                  jens55 @moth4017
                                  last edited by

                                  @moth4017, thanks for your help! I am giving up for today. I am pretty sure that the issue is related to the resurrect.g file but I have no clue why this file would be run when auto save is not enabled. The file is generated by the system and I do not know where it gets the Z offset value from.
                                  I am hoping that somebody with more knowledge can explain to me how resurrect.g is generated, where the Z offset in resurrect.g comes from and why the resurrect.g file would be run if no autosave is enabled.
                                  BTW, resurrect.g calls to execute resurrect-prologue.g but that file does not exist on this printer.

                                  moth4017undefined o_lampeundefined 2 Replies Last reply Reply Quote 0
                                  • moth4017undefined
                                    moth4017 @jens55
                                    last edited by

                                    @jens55 hi, did a test when you press "pause" in DWC it does the following

                                    12/25/2023, 2:20:58 PM Printing paused at X153.7 Y153.2 Z2.7

                                    12/25/2023, 2:20:57 PM Resume state saved
                                    pause
                                    12/25/2023, 2:20:56 PM M25
                                    Resume state saved

                                    <

                                    jens55undefined 1 Reply Last reply Reply Quote 0
                                    • jens55undefined
                                      jens55 @moth4017
                                      last edited by

                                      @moth4017, yes, my setup does the same thing .... everything works just like it should with the exception of DWC reporting a slightly lower Z (but only after it has gone to the correct Z)

                                      moth4017undefined 1 Reply Last reply Reply Quote 0
                                      • moth4017undefined
                                        moth4017 @jens55
                                        last edited by

                                        @jens55 this is a long shot but i think worth doing, do the pause , but then run the resume.g lines of code one by one in the command line and see if this works correctly

                                        <

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                                        • o_lampeundefined
                                          o_lampe @jens55
                                          last edited by

                                          @jens55 said in When a print is paused, Z is reduced by 0.03/0.04 mm on restart:

                                          I am hoping that somebody with more knowledge can explain to me how resurrect.g is generated,

                                          I thinks it's best to raise an official question in the beta firmware section.
                                          Now that you know what to look for, it would be helpful to test the various 3.5rc_ candidates first

                                          jens55undefined 1 Reply Last reply Reply Quote 0
                                          • jens55undefined
                                            jens55 @o_lampe
                                            last edited by jens55

                                            @o_lampe, thanks for weighing in.
                                            I am wildly guessing at this point and grasping at straws. Although the height issue 'seems' to coincide with something in resurrect.g, that file shouldn't actually run according to what I believe.

                                            I did another test by modifying pause.g and resume.g with an M291at the end of each file. I could then see what the head position is at each stage. As it turns out, after resume.g has executed, the nozzle is exactly where it is supposed to be. After I dismiss the message, Z immediately changes from 0.2 to 0.17 (when printing first layer of 0.2 mm) and then it continues printing. I do not know if the nozzle position has actually changed at this point or if the Z display in DWC has just been reset for some reason or other.

                                            So what happens between resume.g finishing and the print process starting back up? Something is obviously telling Z to change.

                                            I checked to see if bed compensation somehow enters the picture but bed compensation, according to the height map, is in the 0.1 range in the area where all this is happening.

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