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

Pressure Advance messing with travel moves

Scheduled Pinned Locked Moved
Tuning and tweaking
6
28
2.7k
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
    gnydick
    last edited by 19 Jan 2019, 06:24

    @dc42

    I noticed that when I have pressure advance enabled, my travel moves are slowed down, not just extruding moves. I believe this shouldn't be the case, correct?

    undefined undefined undefined 3 Replies Last reply 19 Jan 2019, 06:27 Reply Quote 0
    • undefined
      gnydick @gnydick
      last edited by 19 Jan 2019, 06:27

      @gnydick I increased the accel and jerk on the extruder, and now it's not happening.

      1 Reply Last reply Reply Quote 0
      • undefined
        gnydick
        last edited by 19 Jan 2019, 06:30

        Also, I don't think the calibration technique we've been using is valid. When I find the setting where there are no noticeable transitions, my prints end up not being dimensionally correct and slightly misshapen. For example, the maker's muse torture egg, all of the shells are stuck to each other when I use PA but separate when I don't.

        1 Reply Last reply Reply Quote 0
        • undefined
          dc42 administrators @gnydick
          last edited by 19 Jan 2019, 09:40

          @gnydick said in Pressure Advance messing with travel moves:

          @dc42

          I noticed that when I have pressure advance enabled, my travel moves are slowed down, not just extruding moves. I believe this shouldn't be the case, correct?

          You are right, pressure advance should only affect moves in which there is both extruder motion and XY motion.

          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

          undefined 1 Reply Last reply 19 Jan 2019, 21:34 Reply Quote 0
          • undefined
            gnydick @dc42
            last edited by 19 Jan 2019, 21:34

            @dc42 so, you'll look into it? Just because I increase extruder accel and jerk to fix it doesn't mean it's OK.

            Disabling PA also fixed the travel speed.

            undefined 1 Reply Last reply 19 Jan 2019, 22:17 Reply Quote 0
            • undefined
              dc42 administrators @gnydick
              last edited by 19 Jan 2019, 22:17

              @gnydick said in Pressure Advance messing with travel moves:

              @dc42 so, you'll look into it? Just because I increase extruder accel and jerk to fix it doesn't mean it's OK.

              Disabling PA also fixed the travel speed.

              Can you post a video showing the effect? Are absolutely sure that it is pure travel moves that are affected? Do you have anything unusual such as wipe-while-retracting configured in your slicer?

              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
                JohnOCFII @gnydick
                last edited by JohnOCFII 20 Jan 2019, 00:25

                @gnydick What slicer are you using? I'm seeing a very odd slow down when I slice files with Slic3r. Pressure Advance was active, but not sure it is related. I'll re-do that print without PA.

                I notice I also had wipe with retract active. I can turn that off too.

                Related, the simulation time is about what I would expect, but the actual print time is 1.5 times as long as I would expect. The hot-end seems to pause or at least really slow down often.

                undefined 1 Reply Last reply 20 Jan 2019, 00:30 Reply Quote 0
                • undefined
                  gnydick @JohnOCFII
                  last edited by gnydick 20 Jan 2019, 00:30

                  @johnocfii I'm using slic3r also, also with wiping, but no matter what the move is, a wipe isn't anything special, it's just a travel along the path of the object.

                  I'm 100% sure it's not the slicer as disabling PA fixes it. I realize that disabling a feature can make up for a bad setting from the slicer, but it's just not so in this case.

                  undefined 1 Reply Last reply 20 Jan 2019, 04:53 Reply Quote 0
                  • undefined
                    JohnOCFII @gnydick
                    last edited by JohnOCFII 20 Jan 2019, 04:53

                    @gnydick Well, based on my testing, using Pressure Advance together with the experimental "wipe while retract" definitely cause the actual print time to be much longer than the simulated print time when using Slic3r PE version 1.41.2+

                    • Simulated print time: 1:02
                    • Actual print time: 1:37

                    Same model, no wipe with while retract and no Pressure Advance:

                    • Simulated print time: 1:04
                    • Actual print time: 1:07

                    I started doing testing with and without PA and with and without the wipe while retract option. I can also test with S3D.

                    I'm testing with this model: https://www.thingiverse.com/thing:1363023

                    I'm using the following firmware and DWC:

                    Firmware Name: RepRapFirmware for Duet 2 WiFi/Ethernet
                    Firmware Electronics: Duet Ethernet 1.02 or later + DueX5
                    Firmware Version: 2.02(RTOS) (2018-12-24b1)
                    Web Interface Version: 1.22.6

                    undefined 1 Reply Last reply 20 Jan 2019, 05:10 Reply Quote 0
                    • undefined
                      gnydick @JohnOCFII
                      last edited by 20 Jan 2019, 05:10

                      @johnocfii the reason why it's happening, I'm theorizing, is because the wipe happens at travel speed, so there's a negative extrusion while moving fast, so it thinks it's an extrusion move that needs to be smoothed.

                      undefined undefined 2 Replies Last reply 20 Jan 2019, 15:23 Reply Quote 1
                      • undefined
                        JohnOCFII @gnydick
                        last edited by JohnOCFII 20 Jan 2019, 15:23

                        @gnydick Could be. It was suggested that I may need to tweak my settings too. In particular, Extruder Jerk. This is on a CoreXY machine:

                        ; Axis and motor configurations
                        M350 X16 Y16 Z16 E16 I1 ; Configure 16x microstepping with interpolation
                        M92 X200.40 Y200.32 Z1600.0 E820.0 ; Set steps per mm - 1/9/2019 - osh
                        M566 X1000 Y1000 Z30 E20 ; Set maximum instantaneous (jerk) speed changes (mm/min)
                        M906 X1000 Y1000 Z1000 E800 I50 ; Set motor currents (mA) and motor idle factor in per cent
                        M201 X3000 Y3000 Z20 E1000 ; Set accelerations (mm/s^2)
                        M203 X24000 Y24000 Z900 E3600 ; Set maximum speeds (mm/min)

                        John

                        undefined 1 Reply Last reply 20 Jan 2019, 19:13 Reply Quote 0
                        • undefined
                          Phaedrux Moderator @JohnOCFII
                          last edited by 20 Jan 2019, 19:13

                          @johnocfii Yeah the extruder jerk and accel look pretty low.
                          Try 3000 E Jerk and 8000 E Accel

                          Z-Bot CoreXY Build | Thingiverse Profile

                          undefined 1 Reply Last reply 20 Jan 2019, 19:38 Reply Quote 0
                          • undefined
                            JohnOCFII @Phaedrux
                            last edited by 20 Jan 2019, 19:38

                            @phaedrux said in Pressure Advance messing with travel moves:

                            @johnocfii Yeah the extruder jerk and accel look pretty low.
                            Try 3000 E Jerk and 8000 E Accel

                            Thanks - I'll raise them up. That seems like quite a leap. Is there some good guidance on settings?

                            undefined 1 Reply Last reply 20 Jan 2019, 20:19 Reply Quote 0
                            • undefined
                              dc42 administrators @gnydick
                              last edited by 20 Jan 2019, 19:41

                              @gnydick said in Pressure Advance messing with travel moves:

                              @johnocfii the reason why it's happening, I'm theorizing, is because the wipe happens at travel speed, so there's a negative extrusion while moving fast, so it thinks it's an extrusion move that needs to be smoothed.

                              Yes, wipe-while-retract might confuse pressure advance. How does it behave if you turn off wipe-while-retract?

                              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

                              undefined 1 Reply Last reply 20 Jan 2019, 21:32 Reply Quote 0
                              • undefined
                                Phaedrux Moderator @JohnOCFII
                                last edited by Phaedrux 20 Jan 2019, 20:19

                                @johnocfii I should mention that those settings are for a Titan Aero. Direct drive 3:1 with slightly larger than pancake motor. So it's a very responsive system. These settings may not be ideal for a bowden tube system, I'm not sure.

                                From my point of view, the extruder isn't moving much mass at all and it's not traveling very far compared to the other axis, so short quick moves and direction changes aren't as big of an impact as they would be on the other axis. So my settings are high to eliminate any artificial extruder speed limits. It's speed and response will be dictated by the other algorithms at play and the physical limitations of the motor.

                                If you notice any grinding or skipping with those settings tone them down, but for best responsiveness I think you'd want them on the higher end than the lower end.

                                It may also be worth mentioning that I'm not using the slic3r wipe on retract function since I'm using firmware retraction.

                                Z-Bot CoreXY Build | Thingiverse Profile

                                undefined 1 Reply Last reply 20 Jan 2019, 21:39 Reply Quote 0
                                • undefined
                                  JohnOCFII @dc42
                                  last edited by 20 Jan 2019, 21:32

                                  @dc42 I did an actual print last night, and the print time was 1:22. I did a simulation last night, and it was 1:20. But then I did 3 other simulations of the file with and without PA and with and without wipe while retracting, and all had the same 1:20 simulation time. At that point, I shut off the printer (and Duet and went to bed). I just powered up the printer (a RailCore 300ZL) and simulated that file again. Today's simulation showed up at 1:04.

                                  So -- color me confused. Not sure which simulation value is valid. I did not change config.g between simulation runs.

                                  In the mean time, I'm going to increase the extruder jerk and acceleration, which will probably invalidate future tests. For now, I will keep wipe while retracting turned off. I may do some other PA vs. non-PA tests, and will post results if I find the simulation time varies greatly from the actual print time.

                                  Thanks,

                                  John

                                  deckingmanundefined 1 Reply Last reply 20 Jan 2019, 21:40 Reply Quote 0
                                  • undefined
                                    JohnOCFII @Phaedrux
                                    last edited by 20 Jan 2019, 21:39

                                    @phaedrux I'm using the Bondtech BMG but my stepper is not a pancake. I'll work my way up on the settings. Appreciate the education!

                                    FYI - here's am image link of my Y-carriage/extruder.

                                    https://imgur.com/Yh9vgY4

                                    1 Reply Last reply Reply Quote 0
                                    • deckingmanundefined
                                      deckingman @JohnOCFII
                                      last edited by deckingman 20 Jan 2019, 21:40

                                      @johnocfii If it's any help, I'd concur with @Phaedrux that your extruder jerk at 20mm/min is extremely low. I have Bondtech BMGs with Bowden tubes of about 150mm. My E jerk is 3600 mm/min and acceleration is 3,000 mm/sec^2.

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

                                      undefined 1 Reply Last reply 20 Jan 2019, 21:44 Reply Quote 0
                                      • undefined
                                        JohnOCFII @deckingman
                                        last edited by 20 Jan 2019, 21:44

                                        @deckingman Thanks for the confirmation. Mine is a direct setup (for all intents and purposes -- about 40mm between the BMG and my E3D-v6 hot-end).

                                        I'll start with your settings and see how it goes!

                                        1 Reply Last reply Reply Quote 0
                                        • undefined
                                          JohnOCFII
                                          last edited by JohnOCFII 21 Jan 2019, 18:08

                                          I revised my extruder settings as suggested above to the following and also disabled the wipe while retracting setting in Slic3r.

                                          1. The simulation estimate is now accurate to the actual printing time.

                                          2. Speed of the print is inline with what I'd expect.

                                          Thanks to all for your guidance.

                                          ; Axis and motor configurations
                                          M350 X16 Y16 Z16 E16 I1 ; Configure 16x microstepping with interpolation
                                          M566 X1200 Y1200 Z80 E3600 ; Set maximum instantaneous (jerk) speed changes (mm/min)
                                          M906 X1000 Y1000 Z1000 E800 I50 ; Set motor currents (mA) and motor idle factor in per cent
                                          M201 X3000 Y3000 Z20 E3000 ; Set accelerations (mm/s^2)
                                          M203 X24000 Y24000 Z900 E3600 ; Set maximum speeds (mm/min)
                                          deckingmanundefined 1 Reply Last reply 21 Jan 2019, 18:20 Reply Quote 0
                                          1 out of 28
                                          • First post
                                            1/28
                                            Last post
                                          Unless otherwise noted, all forum content is licensed under CC-BY-SA