EDIT: solution is in the comments. TL;Dr retractions ON and INCREASE speed. Both opposite to common knowledge.

I can’t print flexible TPU properly. It’s either foamy, inconsistent extrusion or jam city, nothing else. I wasn’t able to complete a single print properly in a week and probably 50 tries.

Tried

  • 24 hours of active drying
  • speeds of 10-30mm/s
  • flow rate 1-1.2 (100-130%)
  • temps 220-250 (mfg rec is 235-250)
  • 0.4 and 0.6 nozzle
  • Cura and PrusaSlicer

Direct drive (Biqu H2 V2s) on a well-tuned Ender 3 (no issues with ABS, PETG, even nylon). Part fan off. Printing on PP tape (no adhesion issue).

I can get halfway decent looking print with 250C and a Flow rate of ~140% but it eventually jams anyway. Lower temps give super inconsistent extrusion, nozzle spitting chunks intermittently.

At my wits’ end. Any more tips? I don’t have any other TPU ATM, may be just shitty filament? It’s a cheapo polish F3D Filament TPU 93A. Thanks!

  • CrisEnglish
    6·
    1 year ago

    How old is the filament? If you’ve had it a long time perhaps its taken on too much water (once things get to a certain point it can irreversibly make the filament print poorly, even if you try to dry it)

    I’m not super knowledgeable myself, but I hope someone here is able to provide useful guidance

      • CrisEnglish
        1·
        1 year ago

        Gotcha. Good luck finding answers, and If you figure something out on your own time I’m sure folks would love it if you reported back with your findings. Hopefully someone has some helpful insight :)