Jump to content
Ultimaker Community of 3D Printing Experts

PVA Breaking in Feeder

Recommended Posts

While observing my print I noticed that my extruder 2, which holds PVA, continues to "print", but nothing is coming out. All the while Extruder 1 is printing just fine. I begin to think it was a tiny glitch and that the print would self correct, but the PVA material completely stopped extruding even though the Bowden tubes were full of the material. After ending the print I realized that the PVA material broke inside of the feeder which is strange because it had never done that with my previous prints. Can anyone explain why this is happening?  

Share this post

Link to post
Share on other sites

Well don't let the PVA stay hot in the nozzle for more than 10 minutes or it tends to bake itself into a semi permanent gunk.  You need to do repeated hot and cold pulls (do it from the UM3 menu) to get that core cleaned out again.


Not sure what the original cause of your grinding would be but if the filament is too dry it will be brittle (break off the end at the end of the spool to test it) and if it gets too wet then it boils and pops and snaps and I could imagine maybe it can't keep up with demand (too much pressure in nozzle) and would grind to dust back in the feeder.


Try to keep the filament in the bag with the dessicant whenever you aren't using PVA or Nylon.  other filaments aren't so sensitive to humidity.


  • Like 2

Share this post

Link to post
Share on other sites

I recently had that effect of broken PVA too. It actually broke at insertion (when the feeder loads it). Interestingly everything was fine when I cut off the part that was inside the Bowden tube. The room which this happened in was also rather on the dry side.

  • Like 1

Share this post

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now

  • Our picks

    • How to 3D print with reinforced engineering materials
      Ultimaker is hosting a webinar where we explain how you can achieve and maintain a high print success rate using these new reinforced engineering materials. Learn from Ultimaker's Product Manager of Materials and top chemical engineer Bart van As how you can take your 3D printing to that next level.
      • 0 replies
    • "Back To The Future" using Generative Design & Investment Casting
      Designing for light-weight parts is becoming more important, and I’m a firm believer in the need to produce lighter weight, less over-engineered parts for the future. This is for sustainability reasons because we need to be using less raw materials and, in things like transportation, it impacts the energy usage of the product during it’s service life.
        • Like
      • 12 replies

Important Information

Welcome to the Ultimaker Community of 3D printing experts. Visit the following links to read more about our Terms of Use or our Privacy Policy. Thank you!