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Help - Hotend dripping amber colored compound

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I'm printing PLA+ and have a thick amber colored compound dripping down on the side of my hotend. I've wiped it away and there's more coming down.
Can someone please advise on this?

Most every time I pull the silicone sock off the heater block, for a nozzle change or whatever, I see a thin film of some kind of oil left behind on both the inside of the sock and outside of the block. It's never very much, certainly not to this level. Given that it's there whether I have a crippling leak or not, my guess is that it's a byproduct of holding the silicone at a high temperature for a long time. Silicone is a fantastic high-temp material, but it strikes me as likely that cheap grades of silicone are being used to make most socks... for what it's worth, I don't recall seeing that happen with the nice blue socks that came with my Micro-Swiss and Gulfcoast Robotics hot ends (nor whatever brand I got for the Volcano hot end on my Artillery Sidewinder, which are also blue), it's only happened with various brands of cheap black socks off of Amazon.

Your hot end is loose at one of the connection points. On mine it was the nozzle. You need to tighten it up. I had to clean the hot end out before reseating the nozzle.

You don't necessarily need to clean the nozzle and heater block out. I was able to get away with just tightening mine when it was hot. Just a warning, the threads in the heater block should only be addressed when it is hot. It needs to be hot enough to soften any plastic that may be in the threads so you don't strip out threads and it needs to be at or above your maximum extrusion temperature to tighten so the difference in thermal expansion between the three materials (heater block, heat break, nozzle )doesn't result in this happening again.


Thanks for the help. I was a bit concerned because this goop doesn't look like the black filament that I'm printing with. I'll try to tighten the hotend down in a bit.

The pigment is most likely burnt out of the plastic that you are extruding. The brown you see is burnt plastic.

I did some poking around under the silicone sock and you were all correct. It is absolutely pouring over with burnt filament. It's a disaster in there; I just ordered a replacement hot end.

preheat it, you will be able to remove all of it. You might need a new sock however, Get a three pack of those to have on hand.

It’s tricky to clean at high temperature. I haven’t had to replace a block yet, and (cheap) nozzles aren’t worth the effort to clean.

Definitely worth inspecting and replacing the silicone socks every so often.