UM1 Extrusion Problem

[kas 0]

I have been using my UM1 for nearly a year, and it has been working pretty well. Recently, I am seeing a lot of extrusion problems, and I'd appreciate any advice.

Small prints work fine. Larger prints work fine for about 20-30 minutes, and then the rate of material flow slows down significantly, the bowden tube pops out of the top of the extrusion head, and the filament flow stops. I fix the bowden tube, and the next print works fine for the first 20-30 minutes, then the problem presents itself again.

I have completely replaced the hot end, the bowden tube, and the material feed mechanism, but the problem still persists.

Any ideas or suggestions?

 

[peggyb 170]

did you also replace the teflon spacer?

or looked at it closely?

 

[kas 0]

Yes, I had replaced the teflon spacer too.

 

[DidierKlein 729]

Hi,

Does this happen with any type of filament?

 

[kas 0]

Yes, it happens with at least 3 different filaments I have tried. I changed the tube clamp on top of the hot end too, which seems to help keep the bowden tube in place, but the prints are still very thin and porous, and they crumble easily. Any suggestion?

 

[DidierKlein 729]

You said that you replaced the hotend does that include the nozzle?

If not it might be partially clogged maybe?

Have you tried increasing the printing temperature a bit to see if you still have the same effect?

 

[kas 0]

I have tried two different nozzles (both new), and the problem persisted with both. The flow is better when I raise the temperature to 240-250, but the print quality is not good at that high a temperatures (I use PLA).

 

[peggyb 170]

when the nozzle is hot, can you push the filament through by hand by turning the feeder wheel? Does the filament come out as a regular strand?

Check also in the feeder mechanism, when it is opened, if the little black wheel can turn freely.

Check if there is any filament dust on the knurled bolt in the feeder mechanism….. what else to check?...

 

[LePaul 321]

How about the latch that closes up the extruder? Is there any slack in there?

 

[kas 0]

Thank you all for your suggestions. It turned out the problem was the extruder motor.