UM3 Filament Jam (PLA)

[robotgrrl 0]

This isn't so much as a question as it is sharing our process of our debugging and getting filament to extrude again on an Ultimaker 3.

After a failed 6 hour dual-extrusion print, printer core #1 stopped extruding. Here's our process of what we did to make it work again:

1) Load material #1 (didn't work)

2) Unload material #1 (still didn't work)

3) Removed the plastic tube going to printer core #1

4) Set printer core #1 temperature to 230 deg C

5) Pulled out the filament (gently)

6) Unloading material #1 (still didn't work)

7) Unloading material #1 while pulling the filament out of the motor area

The filament that was pulled out was significantly eroded where the drive wheel was trying to push it. The first tries at unloading and loading no longer worked because of this.

After this, we made the mistake of loading the filament when it is spinning faster. This meant that the distance was not enough to go to the print core. So when we did this process again, the filament went rushing into the print core.

We then unloaded the filament, and made sure to load it when the motor was spinning slower. For some reason, loading filament is a really cumbersome process (or so we found).

With printer core #1 working, we ran a test print and found #2 was now not working. So the unloading process was repeated with #2, and we found a similar (but less extreme) case as #1, where the filament was worn down where the drive wheel must have been trying to move it.

Two fixes we are making for retrying the print:

- Not mounting filament spool #1 on the back - it's now on a separate spool holder

- Extruder temperatures up to 220 deg C

We'll see how it goes and if there's another fail. Hope this feedback / process is helpful to any UM3 newbies out there.