<p>The fitting can be defective and no longer hold upon the PTFE tube anymore. In that case, you need to cut off a short piece of the tube and most likely replace the fitting.</p>
<p>If the metal coupler <em>unscrews</em> you can fix that by properly screwing it <em>tight</em>. If it does not stay put after applying some torque upon it, then the screw thread is broken, and the whole extruder gearing-setup needs to be replaced. An aluminium swap part costs about 10 to 15 €.</p>

CC BY-SA 4.0
2021-01-02T05:45:20.540Z
I’ll agree that the threads must be damaged. On my Ender 3 Pro, that connector is only tightened finger tight and it never unscrews by itself.
DoxyLover
CC BY-SA 4.0
2021-01-03T19:46:40.507Z
@DoxyLover I unscrew that end regularily because it makes loading easier :3
Trish
CC BY-SA 4.0
2021-01-04T12:59:11.100Z
@Trish If you put a bevel on the inside of the PTFE tube, that can make loading easier.
Andrew Morton
CC BY-SA 4.0
2021-01-04T13:12:06.487Z
@AndrewMorton no, it's a problem with the fitting bevel being too small, a tiny lip that the filament hits on loading on the fitting.
Trish
CC BY-SA 4.0
2021-01-04T13:39:54.113Z
@Trish A slightly different cause than when I had a similar problem, then. It's amazing that 3d printing can work at all with so many things to go wrong :)
Andrew Morton
CC BY-SA 4.0
2021-01-04T13:41:44.103Z
@AndrewMorton no, it's a wonder so many general rules of thumb do work with how different many things are XD
Trish
CC BY-SA 4.0
2021-01-04T21:19:26.623Z
It was simply unscrewing.  The threads didn't look damaged so I simply tightened a bit more (with a wrench this time instead of just my fingers) and added a bit of loctite (the removable kind) and its held for two prints so far.
Joseph Crozier
CC BY-SA 4.0
2021-01-02T02:24:12.910Z
2021-01-02T02:24:12.910Z
Trish
<p>If the fitting is remaining attached to the PTFE tubing, that would indicate that the threaded end of the fitting is pulling out of the drive assembly. This implies that the internal threads of the drive assembly have stripped out. This is not unusual for a plastic drive assembly.</p>
<p>The best solution is to replace the drive assembly. I believe I paid about US$12 for the last one I purchased and it was aluminum, not plastic. A quick search for &quot;Ender 3 drive mechanism&quot; returned a number of choices. One of them from <a href="https://rads.stackoverflow.com/amzn/click/com/B07SY745CF" rel="nofollow noreferrer" rel="nofollow noreferrer">Amazon</a> (14.98) is anodized aluminum and purports to be improved over the original.</p>
<p><a href="https://i.sstatic.net/bT6mO.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/bT6mO.jpg" alt="ender 3 compatible drive assembly" /></a></p>
<p>A less than ideal solution would involve drilling out the stripped threads and installing an insert (sometimes called a Heli-coil™) but that could be as expensive as a replacement mechanism.</p>

CC BY-SA 4.0
2021-01-02T01:51:58.230Z
2021-01-02T01:51:58.230Z
fred_dot_u
<p>I keep having a recurring problem with my ender 3 pro.  The bowden tube keeps popping off here (pictured)</p>
<p><a href="https://i.sstatic.net/hWvUQ.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/hWvUQ.jpg" alt="enter image description here" /></a></p>
<p>I've read elsewhere online where people are having a similar problem, i.e. the ptfe tube is actually popping out, but I don't know if thats the case here.  It's staying attached to the metal coupler, but that metal coupler is unscrewing during the course of the print and falling out.  Any tips to fix it?  New one? Some sort of loc-tite to get it to not unscrew?  Any ideas?</p>

<creality-ender-3>
Ender 3 Bowden tube popping off
Joseph Crozier
# Ender 3 Bowden tube popping off

(Asked by: username_0 on 2021-01-02)

I keep having a recurring problem with my ender 3 pro. The bowden tube keeps popping off here (pictured)

[![enter image description here](https://i.sstatic.net/hWvUQ.jpg)](https://i.sstatic.net/hWvUQ.jpg)

I've read elsewhere online where people are having a similar problem, i.e. the ptfe tube is actually popping out, but I don't know if thats the case here. It's staying attached to the metal coupler, but that metal coupler is unscrewing during the course of the print and falling out. Any tips to fix it? New one? Some sort of loc-tite to get it to not unscrew? Any ideas?

**Tags:** creality-ender-3

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## 2 answers

### Answer by username_1 on 2021-01-02. Score: 2 | Accepted answer

The fitting can be defective and no longer hold upon the PTFE tube anymore. In that case, you need to cut off a short piece of the tube and most likely replace the fitting.

If the metal coupler *unscrews* you can fix that by properly screwing it *tight*. If it does not stay put after applying some torque upon it, then the screw thread is broken, and the whole extruder gearing-setup needs to be replaced. An aluminium swap part costs about 10 to 15 €.

> **Comments:**
> **username_2**: I’ll agree that the threads must be damaged. On my Ender 3 Pro, that connector is only tightened finger tight and it never unscrews by itself.  
> **username_1**: @DoxyLover I unscrew that end regularily because it makes loading easier :3  
> **username_3**: @Trish If you put a bevel on the inside of the PTFE tube, that can make loading easier.  
> **username_1**: @AndrewMorton no, it's a problem with the fitting bevel being too small, a tiny lip that the filament hits on loading on the fitting.  
> **username_3**: @Trish A slightly different cause than when I had a similar problem, then. It's amazing that 3d printing can work at all with so many things to go wrong :)  
> **username_1**: @AndrewMorton no, it's a wonder so many general rules of thumb do work with how different many things are XD  
> **username_0**: It was simply unscrewing.  The threads didn't look damaged so I simply tightened a bit more (with a wrench this time instead of just my fingers) and added a bit of loctite (the removable kind) and its held for two prints so far.  

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### Answer by username_4 on 2021-01-02. Score: 3

If the fitting is remaining attached to the PTFE tubing, that would indicate that the threaded end of the fitting is pulling out of the drive assembly. This implies that the internal threads of the drive assembly have stripped out. This is not unusual for a plastic drive assembly.

The best solution is to replace the drive assembly. I believe I paid about US$12 for the last one I purchased and it was aluminum, not plastic. A quick search for "Ender 3 drive mechanism" returned a number of choices. One of them from [Amazon](https://rads.stackoverflow.com/amzn/click/com/B07SY745CF) (14.98) is anodized aluminum and purports to be improved over the original.

[![ender 3 compatible drive assembly](https://i.sstatic.net/bT6mO.jpg)](https://i.sstatic.net/bT6mO.jpg)

A less than ideal solution would involve drilling out the stripped threads and installing an insert (sometimes called a Heli-coil™) but that could be as expensive as a replacement mechanism.


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