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

    Extrusion issue? Cooling Issue? Something else?

    Scheduled Pinned Locked Moved
    Tuning and tweaking
    6
    17
    2.5k
    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.
    • JohnOCFIIundefined
      JohnOCFII
      last edited by

      Yes, I've got the standard 40mm fan and nozzle as shipped with the T3P3 Kossel Mini. I agree, it almost looks like the fan stopped working. I just turned on the printer now and confirmed the parts cooling fan is still working, but I don't recall if I looked at it during the Benchy print.

      https://docs.google.com/document/d/1kCky9gNnUOsWN_fntAT6vUc3SMkjG3exQ_DxXZ9MSZc/pub

      Thanks,

      John

      1 Reply Last reply Reply Quote 0
      • JohnOCFIIundefined
        JohnOCFII
        last edited by

        It was a good day of experimenting. I modified extrusion multiplier. I modified retraction and Z-Hop settings. What was finally clear at the end of the testing is that the primary problem is poor cooling (as David suggested above). While my parts cooling fan is functioning, it appears not to cool well enough to complete the 3D Benchy.

        I finally proved this to myself by turning the ship around. Immediately, the stern started to come out nicely, and instead the bow had issues.

        The first four 3D Benchy's (from the left) had the stern towards the rear of the Kossel Mini (away from the parts cooling fan nozzle) The last two had the stern towards the fan.

        And a short video showing the nozzle dragging through the soft bow:
        https://youtu.be/OsPJlGTsUmY

        Understanding the cause of the problem makes me feel better about the issue. I'll have to put "enhanced parts cooling" on my list of upgrades. 🙂

        Thanks,

        John

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

          I have the same fan duct design on my delta, and I think the height of the slot that the air comes out of is too great. I intend to reprint it with a shallower slot. However, it may be that you need a Berd-Air or similar all-round cooling system to print good overhangs in all directions.

          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
          • JohnOCFIIundefined
            JohnOCFII
            last edited by

            The Berd-Air nozzle looks to be excellent for all-around cooling. On my Prusa i3 MK2, they use a 50mm blower-style fan with a slotted nozzle that is a bit narrower than the default nozzle on the T3P3, and it has pushes enough air to cool the 3D Benchy. I might start out that route, but as long as I know it can be solved, I'm happy.

            http://e3d-online.com/50x50x15mm-12v-DC-Side-Blow-Fan

            John

            1 Reply Last reply Reply Quote 0
            • JohnOCFIIundefined
              JohnOCFII
              last edited by

              I found these tests to be interesting:

              http://www.desiquintans.com/coolingtests

              http://www.desiquintans.com/coolingtests2

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

                I have a T3P3 Kossel XL and I decided to make a new print fan duct. It should also work on the mini. It's not perfect but I believe it works better than the original.

                Here's the STL files and the original SCAD file:

                https://www.dropbox.com/s/uk8wdzlcvps34r4/kossel-fan-duct-mb-v1.scad?raw=1

                https://www.dropbox.com/s/vp95ca5aprixyyn/kossel-fan-duct-mb-v1-bracket.stl?raw=1

                https://www.dropbox.com/s/ues81fvlylgjkb6/kossel-fan-duct-mb-v1.stl?raw=1

                1 Reply Last reply Reply Quote 0
                • sigxcpuundefined
                  sigxcpu
                  last edited by

                  Short version: radial fan - good, axial fan - bad.
                  Long version: an axial fan at the sizes we use has almost zero pressure capability. Best wait to use it is without a funnel, but that spreads air all over the place. What is really needed is some small nozzle(s) to get high air speed, because the printhead will not stay in the same place for too long (see hair dryers). This requires pressure, so the best candidate is a radial fan, aka "blower".

                  A turbine axial fan rotating at high speed will do it too, just like the above mentioned hair dryer, but who has one and who wants to hear jet take-off noise when printing?

                  1 Reply Last reply Reply Quote 0
                  • JohnOCFIIundefined
                    JohnOCFII
                    last edited by

                    I've order a 50mm blower-style fan (like the E3D unit linked above). Now to think about how to mount it without re-doing the whole spider. Ideally I can just connect a new mount/funnel to the existing T3P3 spider using the same attachment points.

                    1 Reply Last reply Reply Quote 0
                    • JohnOCFIIundefined
                      JohnOCFII
                      last edited by

                      @burtoogle:

                      I have a T3P3 Kossel XL and I decided to make a new print fan duct. It should also work on the mini. It's not perfect but I believe it works better than the original.

                      I've used a small Eiffel tower for fan tests on my first delta printer. Some guys have made a similar two-pronged nozzle for the blower-style fan on the MK2, to good effect.

                      John

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

                        I find that I still sometimes have to rotate the model "into wind" to get the best cooling but it's really OK for most models. The problem I found with the original duct was that most of the air was blowing backwards through the fan (as mentioned above, axial fans struggle to blow air through a small outlet). So I reasoned that having 3 outlets would be good as the total outlet area was larger and the air is blowing at the model from 3 directions (well, that's the theory, anyway!)

                        1 Reply Last reply Reply Quote 0
                        • JohnOCFIIundefined
                          JohnOCFII
                          last edited by

                          A colleague modified a blower nozzle that he created for the Prusa i3 MK2 to be used with my T3P3 Kossel Mini R3. I finally got it mounted and recalibrated the printer this week. The results are very good! With the stock cooling fan, I could not even complete the 3D Benchy (as shown above in this thread).

                          Main downside at this point is the fan is reducing my print area on one side of the bed. It looks like the fan can be tilted up more to get some of that back. To really reduce the issue, I'd have to go with mounting the blower above the effector.

                          Left side is from Prusa i3 MK2. Right side is from T3P3 Kossel Mini R3. The left rear corner of the boat is the only area that start to get a bit soft. The rear nameplate is a bit less clear. The chimney is not quite as nice. Both are printed with Prusa PLA. Both sliced with S3D v4.0 with .2 layer height and similar settings for speed, etc.

                          Note the area where the fan could be tilted up closer to the hot-end. Just needs to clear the rod ends.

                          John

                          1 Reply Last reply Reply Quote 0
                          • number40fanundefined
                            number40fan
                            last edited by

                            http://www.ebay.com/itm/Lot-2pcs-Ball-Bearing-4cm-40mm-x-10mm-Blower-Fan-12V-Brushless-Cooling-fan-2pin/263060496493?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

                            Grab a set of these. Saves a lot of room and they push some air. With my fan and nozzle, it is right at 50mm tall and fits under my effector mounted vertically. Working on a new mount to put both fans on there.

                            1 Reply Last reply Reply Quote 0
                            • tech-ratonundefined
                              tech-raton
                              last edited by

                              Had the same problems.

                              After numerous itérations, I ended with this solution.

                              https://www.thingiverse.com/thing:2378545

                              With 100% PWM, I experienced delamination.
                              50% would be enough for bridging.

                              And With 2 blower at 100%PWM, it becomes a little bit noisy…

                              1 Reply Last reply Reply Quote 0
                              • JohnOCFIIundefined
                                JohnOCFII
                                last edited by

                                Yeah, the 40mm fan would certainly fit better. I'd guess the airflow would be good enough. The airflow from the 50mm blower-style fan is such that I can readily turn it down on most prints.

                                Tech-ration's solution is interesting as well!

                                Now that I'm investigating Haydn's effector for magnetic rods, I'll have to see what solutions work with that.

                                Thanks, guys.

                                1 Reply Last reply Reply Quote 0
                                • JohnOCFIIundefined
                                  JohnOCFII
                                  last edited by

                                  @number40fan:

                                  http://www.ebay.com/itm/Lot-2pcs-Ball-Bearing-4cm-40mm-x-10mm-Blower-Fan-12V-Brushless-Cooling-fan-2pin/263060496493?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2060353.m2749.l2649

                                  Grab a set of these. Saves a lot of room and they push some air. With my fan and nozzle, it is right at 50mm tall and fits under my effector mounted vertically. Working on a new mount to put both fans on there.

                                  I ordered the set of two. Thanks for the link!

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