This is a Prusa MINI+ that has worked flawlessly for 3 months. Suddenly the prints won’t stick to the bed, the first layer is all messy and I cancel the print before anything worse happens.

  • The printer has auto bed leveling so I would rule that out.
  • The plate is cleaned with 70% IPA, so it’s not dirty either.
  • I have tried to adjust the “Live Z Adjust” while printing that first layer, but no setting works well.
  • Each filament is printed at recommended temps (+/- 215C) and bed is at 60C.
  • Out of my 5 spools, only 1 works well: RepRapper 3-color PLA. Even the Prusament PLA fails to stick well, and also eSun PLA+, and eSun matte PLA, and Tinmorry TPU.

https://i.imgur.com/MEpK37W.png

Update:

  • Thank you all for your kind input.
  • I washed the plate, and cleaned the nozzle (have no spare nozzle).
  • I also did a fresh Z-test (with this object) using Prusament galaxy silver PLA.
  • That was successful and showed that my height was already very close to perfect.
  • Z-test result shows that -1.425 is best. I was off by only 0.025. Image
  • Started printing an object with eSun matte black PLA but the result was same as in my original photo.
  • Changed back to the Prusament galaxy silver PLA and the result is perfect. (image)

So it looks like my filament storage is not up to snuff! Good thing that I only have a few spools, so not much is lost.

  • Thanks4NothingEnglish
    2•11 months ago

    My money would be a clogged nozzle. But a better photo (close up) may be helpful. Things I wonder…

    Does the filament come out and curl back up during preheat?

    Is your heat block messy with residue?

    Have you tried a cold pull, or pulling the nozzle and cleaning/replacing it?

    • Thanks4NothingEnglish
      3•11 months ago

      I forgot until looking at your photo that the mini uses a Bowden tube, not direct drive like the MK3S+. Did you replace/switch the nozzle around the time this all started happening? With Bowden tubes, there are a few problems that can arise that you don’t see on direct drive. The end of the Bowden tube (that is inside the extruder/hote end assembly) can get deformed or clogged. If you can check that, you may find an issue. Other than that, when swapping nozzles I always had to put the nozzle in part of the way, then push the Bowden in further, then tighten the nozzle.