SOLVED!
Symptoms: Printing starts nicely, but after a short time the printhead is blocked and no material rendered any more.
Issue: Axial fan (the front fan) was blocked by debris, thus the feed in the printhead would overheat and the material would get to soft.
Analysis: Start your Ultimaker, go to System -> Printheads -> Temperature and set the temperature to roughly 50°. Verify whether the front fan is activated. If not, this is your problem.
Solution: Cleaning out the axial fan using tweezers; to do so, you might have to dismantle the printhead.
Resources:
* How to exchange the axial fan: https://support.ultimaker.com/hc/en-us/articles/360012826479-Replace-the-axial-fan-of-the-Ultimaker-3
* Guide on other possible issues causing the symptoms: https://support.ultimaker.com/hc/en-us/articles/360012112739-How-to-fix-feeder-issues
* The fan's serial number (in case you have to exchange it) changed, the original one is not in production anymore (at least the one in my Ultimaker). The currently (end of 2020) available one is MF35100V2-A99-A from SUNON.
ORIGINAL POST:
Hello,
My Ultimaker 3 has been printing nicely for quite some time, but the Feeder 1 is currently not forwarding enough material, only dropping occasional dots of PLA. Usually, it starts out nicely, with e.g. borderlines printed properly. But after minutes, it clogs up and doesn't print any more.
I already tried to clean the print head, cleaned the feeder itself incl. dismantling it, cleaning it out and putting it back together, and I also changed the material. I also tried to change the pressure of the feeder, all to no avail so far. I did only a visual check of the bowden tube, there doesn't seem to be any debris creating additional friction.
Sometimes the feeder really grinds into the material, and you see where it was blocked, but quite often it also is only having slight signs of having been blocked (just a bit of additional material taken away, no full grind).
I'm a bit lost what might be the reason, anyone has had such stubborn levels of non-feeding already?
Thanks for your help!
Stefan