<p>I'm not sure what this gunk is, but it seems to be standard in Creality hotends and is presumably something they used to hold the threads or improve thermal properties or something. In any case it does not seem important. You do not need to replace your heat sink.</p>
<p>If the gunk is making it hard to re-insert the bowden tube and threaded coupler, or if it looks like you're going to push it down where it would get in the interface between the tube and the nozzle and cause a clog (this seems likely from your pic), you can clean it out with a Q-tip and some IPA. Otherwise, in my experience it's fine to ignore it.</p>

CC BY-SA 4.0
2023-01-19T10:14:06.137Z
2023-01-19T10:14:06.137Z
R.. GitHub STOP HELPING ICE
<p>That looks burned and rough.  It is likely to prevent the bowden tube from properly seating, and if that falls into the nozzle, it could clog it.</p>
<p>That may be plastic that leaked between the hot end and the bowden tube and degraded under heat over time.  When my printer was new, I took apart the hot end and didn't find any residue like this, but when I changed my nozzle recently, I did.  I think this is buildup over time of either degraded plastic or residue that was on the plastic.</p>
<p>I would recommend removing the nozzle and using a q-tip or a skewer to scrape that out and push it out of the hot end.</p>
<p>Also check the end of your bowden tube and make sure it isn't also charred or contaminated with residue.  Clean it and make sure that the end is flat so that it can seat fully into the hot end with no gaps.  If the tip looks damaged, you can insert it into a loose coupler and use a sharp blade to cut the tip even with the end of the coupler.</p>

CC BY-SA 4.0
2023-01-22T14:08:14.063Z
2023-01-22T14:36:39.017Z
2023-01-22T14:36:39.017Z
user10489
<p>I recently had some filament get stuck in the Bowden tube so much so that I had to remove it from the stock Creality heatsink on my Ender 3 v2. As I was taking the tube out of the heatsink I noticed some residue inside:</p>
<p><a href="https://i.sstatic.net/MRhQR.jpg" rel="nofollow noreferrer" title="Photo of the Creality stock heatsink with some type of residue inside"><img src="https://i.sstatic.net/MRhQR.jpg" alt="Photo of the Creality stock heatsink with some type of residue inside" title="Photo of the Creality stock heatsink with some type of residue inside" /></a></p>
<p>Do I have to replace my heatsink or can it be cleaned out? What is this residue? Will this cause problems in the future?</p>

<nozzle><maintenance>
Residue inside of heatsink
agarza
# Residue inside of heatsink

(Asked by: username_0 on 2023-01-19)

I recently had some filament get stuck in the Bowden tube so much so that I had to remove it from the stock Creality heatsink on my Ender 3 v2. As I was taking the tube out of the heatsink I noticed some residue inside:

[![Photo of the Creality stock heatsink with some type of residue inside](https://i.sstatic.net/MRhQR.jpg "Photo of the Creality stock heatsink with some type of residue inside")](https://i.sstatic.net/MRhQR.jpg "Photo of the Creality stock heatsink with some type of residue inside")

Do I have to replace my heatsink or can it be cleaned out? What is this residue? Will this cause problems in the future?

**Tags:** nozzle, maintenance

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## 2 answers

### Answer by username_1 on 2023-01-19. Score: 2

I'm not sure what this gunk is, but it seems to be standard in Creality hotends and is presumably something they used to hold the threads or improve thermal properties or something. In any case it does not seem important. You do not need to replace your heat sink.

If the gunk is making it hard to re-insert the bowden tube and threaded coupler, or if it looks like you're going to push it down where it would get in the interface between the tube and the nozzle and cause a clog (this seems likely from your pic), you can clean it out with a Q-tip and some IPA. Otherwise, in my experience it's fine to ignore it.


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### Answer by username_2 on 2023-01-22. Score: 1

That looks burned and rough. It is likely to prevent the bowden tube from properly seating, and if that falls into the nozzle, it could clog it.

That may be plastic that leaked between the hot end and the bowden tube and degraded under heat over time. When my printer was new, I took apart the hot end and didn't find any residue like this, but when I changed my nozzle recently, I did. I think this is buildup over time of either degraded plastic or residue that was on the plastic.

I would recommend removing the nozzle and using a q-tip or a skewer to scrape that out and push it out of the hot end.

Also check the end of your bowden tube and make sure it isn't also charred or contaminated with residue. Clean it and make sure that the end is flat so that it can seat fully into the hot end with no gaps. If the tip looks damaged, you can insert it into a loose coupler and use a sharp blade to cut the tip even with the end of the coupler.


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