<p>A seal between the heat break and nozzle should be achieved by tightening them while the hotend is hot. After assembling the (cold) hotend, heat it up to somewhat above the highest temperature you will print at and then tighten the nozzle some more. When it cools down again, you will have a very tight seal. If the nozzle still leaks after this tightening then it is defective.</p>
<p>Using teflon is possible but will limit the maximum temperature you can use your hotend at safely and you won't be able to print some higher temperature materials.</p>

CC BY-SA 4.0
2020-12-24T13:38:41.777Z
2020-12-24T13:38:41.777Z
Tom van der Zanden
<p>Thinking this over, the best place to seal the hotend is between the throat tube and nozzle.  What are the advantages/disadvantages of an integrated nozzle and throat to make this seal?  Does a throat with a Teflon tube improve this seal?   Is it reasonable to cut a gasket out of 3mm ID 5mm OD Teflon tubing to make the seal for M6 thread parts?
I intend these questions to all address the main question to prevent a leaky hot end.</p>
<p><a href="https://i.sstatic.net/WK1Ac.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/WK1Ac.png" alt="Throat Tube" /></a><a href="https://i.sstatic.net/c3jiO.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/c3jiO.png" alt="nozzle" /></a>
<a href="https://i.sstatic.net/kOAYX.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/kOAYX.png" alt="Integrated throat a nozzle" /></a>
<a href="https://i.sstatic.net/h3FpJ.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/h3FpJ.png" alt="Throat with Teflon tube" /></a></p>

CC BY-SA 4.0
2020-12-24T13:34:58.817Z
What you refer to as "throat" is more commonly referred to as "heat break". The term "throat", which is admittedly becoming more and more common, I believe originates in bad translation from Chinese.
Tom van der Zanden
<troubleshooting><hotend>
What technics are you using to seal between the throat tube and nozzle?
Perry Webb
# What technics are you using to seal between the throat tube and nozzle?

(Asked by: username_0 on 2020-12-24)

Thinking this over, the best place to seal the hotend is between the throat tube and nozzle. What are the advantages/disadvantages of an integrated nozzle and throat to make this seal? Does a throat with a Teflon tube improve this seal? Is it reasonable to cut a gasket out of 3mm ID 5mm OD Teflon tubing to make the seal for M6 thread parts?
I intend these questions to all address the main question to prevent a leaky hot end.

[![Throat Tube](https://i.sstatic.net/WK1Ac.png)](https://i.sstatic.net/WK1Ac.png)[![nozzle](https://i.sstatic.net/c3jiO.png)](https://i.sstatic.net/c3jiO.png)
[![Integrated throat a nozzle](https://i.sstatic.net/kOAYX.png)](https://i.sstatic.net/kOAYX.png)
[![Throat with Teflon tube](https://i.sstatic.net/h3FpJ.png)](https://i.sstatic.net/h3FpJ.png)

**Tags:** troubleshooting, hotend

> **Comments:**
> **username_1**: What you refer to as "throat" is more commonly referred to as "heat break". The term "throat", which is admittedly becoming more and more common, I believe originates in bad translation from Chinese.  

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## 1 answers

### Answer by username_1 on 2020-12-24. Score: 2 | Accepted answer

A seal between the heat break and nozzle should be achieved by tightening them while the hotend is hot. After assembling the (cold) hotend, heat it up to somewhat above the highest temperature you will print at and then tighten the nozzle some more. When it cools down again, you will have a very tight seal. If the nozzle still leaks after this tightening then it is defective.

Using teflon is possible but will limit the maximum temperature you can use your hotend at safely and you won't be able to print some higher temperature materials.


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