I've noticed some strange black goo on some of my prints lately (haven't been

I’ve noticed some strange black goo on some of my prints lately (haven’t been able to snag a decent pic yet). Looking at my j-head, it looks like it could be coming from around the heating resistor; has anyone seen anything like that before?

It’s possible that it’s just strings of filament that have gotten melted to the hot end and sat there for a while until discoloring.

Yes, on the eMaker Huxley.

This printer has a Bowden cable filament feed.

In the instructions it is recommended that you heat the hot end parts prior to assembly.

If you don’t do this then it is possible that some of the plastic will leak out of the threads on to the top of the hot end assembly where it sort of cooks into a black liquid which then drips down straight on top of your print leaving the odd black spots which you wonder where the hell they came from!

I have noticed this leak out from the PEEK part of my Chinese J-Head. I suspect it to be the black coloring of the PEEK or residue from the stuff they use to prevent leaking (That need to be replaced with PTFE tape or whatever one should use to prevent leaking). It stopped after a while, I just used a Q-tip to wipe it away rom time to time.