Lulzbot Taz 5 Filament Issue??

[dunginhawk]

Good morning... So i finally got my taz going again after some filament jams due to peek heating.
Now im seeing a lot of burnt material in my prints, see below




I have the temp set at 195, which is fairly low compared to what i usually print at. Im also seeing a bit of over extrusion, so i may dial that back to .9 like S3Ds default. Perhaps that would help with the strining black stuff.
any other thoughts ?
thanks

[Roxy]

The burnt (and discolored plastic) can come from two places. Over time, especially if you switch plastic types back and forth, you can get plastic that just cooks inside the nozzle. But I doubt that is happening. The other thing that happens is you get some plastic that did not stick to the print on the side (or edge) of the nozzle. It just sits there and cooks while the printer is doing its thing. But eventually, the nozzle goes some where that cooking plastic touches the print and it gets pulled off. A corner that is raising is a good example of how that can happen.

Probably... Cutting back on the over extruding is going to help this problem.

[dunginhawk]

I think your 2nd assessment is right on, and thats kind of what i was thinking too, because examining the nozzle now, there is a bit of oozing from the nozzle to heater block part (needs to be heated and screwed tighter.
Ill see what i can do