I’ve been repairing a Creality CR-10S Pro V2 and can’t figure out this persistent oddity. It prints spiral vases and benchies flawlessly, but regular 3D prints often have these pronounced bumps and thick whiskers sticking out. I think it’s more than just Z seam blobs, I’m wondering if it’s an issue with the wipe settings not working well in PrusaSlicer…

Here’s another example of the issue: https://i.imgur.com/ZHssQWI.jpg

I’m using Kaaber transparent PETG, printing at 215/210 nozzle and 75 bed. I know this seems cool for PETG, but this brand tends to melt and ooze at anything hotter.

Here are my PrusaSlicer retraction settings, they are the default for this printer:

https://i.imgur.com/RqrltUL.jpg

I tried slightly bumping the retraction to 6.5mm and 65mm/s, but it made no difference.

Any ideas what would cause this? I’m getting it while trying to print many parts of the honeycomb storage wall off printables.

  • Square Singer@feddit.deEnglish
    6·
    1 year ago

    There is a slicer option that covers this problem up in many cases. It will not work in every case and it will not fix the underlying issue, but in this case it would have fixed it: Avoid crossing Perimeters.

    You get these artifacts from filament dripping from your nozzle when the nozzle is traveling over empty area. The option above avoids traveling over empty space if possible.

  • ThatGuyFromWork@lemm.eeEnglish
    5·
    1 year ago

    You may be running the nozzle too hot for this filament. Trying lowering your temps more and see if that changes anything. Usually when my temps are high, that’s the first thing I see

  • wizzor@sopuli.xyzEnglish
    4·
    1 year ago

    I would try with another slicer to be safe. I trust you have cleaned your nozzle too?

    • poofy_cat@lemm.eeOPEnglish
      1·
      1 year ago

      I’ve tried this with 0.6 and 0.4 nozzles, both had the same issue. And I make sure they are clean to start. I’ve also replaced the bowden tube and extruder, both of which didn’t improve this hah.

      • wizzor@sopuli.xyzEnglish
        1·
        1 year ago

        Any chance there is moisture in the filament? I know I’m grasping at straws here…

  • skilltheamps@feddit.deEnglish
    2·
    1 year ago

    As many other stated, its nozzle ooze. When you travel the same path repeatedly, it will catch on previous ooze and build these diagonal structures.

    Besides what other wrote, I can recommend:

    • Try out how fast you can make your printer move, and travel as fast as possible. That gives your filament less time to ooze, and therefore you minimize the amount.
    • When travelling, do a very small Z-hop. Something like .1mm. That helps a bit to not deposit the oozed material along the way, but where you touch down again. If you make the Z-hop too high, it will start to create strings. So you’ll have to try and tune this value.
    • Generally try to slice in a way that minimizes travels. Even stuff like choosing an infill that doesn’t cross lines, and connecting those lines so that you print long and steady can help to keep your nozzle clean (I like gyroid with connected ends for that matter).
    • What also helps is to convert your printer do direct drive. That gives more precise retractions. What works well for me is direct drive with small retractions. I believe, not shoving the filament back and forth so much yields better quality. Maybe, because retracting a large amount pulls air into the hot-end, and I imagine it might not all come out perfectly again when continuing with the next perimeter.
  • stevestevesteve@lemmy.worldEnglish
    31·
    1 year ago

    This is basically just nozzle ooze. those little bumps are the extra plastic that’s come out when the nozzle is traveling.

    I’m not familiar with prusaslicer, but in Cura there are settings called combing that help prevent the nozzle from traveling over plain air (thus the ooze gets left in the walls or infill), that might help, but honestly I’ve had this same problem and I’d love to hear if you find a good solution for it.

  • poofy_cat@lemm.eeOPEnglish
    1·
    1 year ago

    As an update, changing to a different brand of petg (polar filament) fixed it. I also changed to 230 nozzle and 70 bed, which is the recommended temp from the manufacturer for this new petg… the old transparent petg (from Kaaber) couldn’t handle these temperatures without liquefying and sucking on overhangs/bridges.