<p>One of the things I look for is if you pull the print head a good ways off the bed and have it extrude. It should just squirt plastic straight down.  If it bends sharply in one direction, or even curls back on itself, then that is a sign of damage. </p>

CC BY-SA 3.0
2017-05-13T23:37:46.727Z
2017-05-15T11:26:28.657Z
2017-05-15T11:26:28.657Z
Jared Perkins
<p>According to <div class="youtube-embed"><div>
                <iframe width="640px" height="395px" src="https://www.youtube.com/embed/uvlMeTnjriQ?start=0"></iframe>
            </div></div> the inner diameter doesn't change much, but, as said by @0scar, the nozzle shortens and at the end you get to the inner cavity.</p>

<p>Check the length and you are done.</p>

CC BY-SA 4.0
2019-09-04T12:23:16.117Z
2019-09-04T12:23:16.117Z
FarO
<p><strong>TL;DR</strong> You could compare the nozzle to a similar new nozzle to look for wear.</p>

<hr>

<p>The creators of the <a href="https://olssonruby.com/anders-olsson-olsson-ruby/" rel="nofollow noreferrer">Olsson Ruby Nozzle</a> have published some pictures of wear on brass, steel and hardened steel nozzles. From <a href="https://olssonruby.com/design-quality/" rel="nofollow noreferrer">their website</a> the following image is taken:</p>

<p><a href="https://i.sstatic.net/drWLD.png" rel="nofollow noreferrer"><img src="https://i.sstatic.net/drWLD.png" alt="Nozzle wear"></a></p>

<p>Depending on the amount of filament that is being printed, not only the internal dimensions, but also the outer dimension change considerably. This is clearly visible in the images. Comparing your nozzle to a similar new nozzle might give you an idea of the wear of your nozzle. It is expected that long before the nozzle reaches this state, you need to readjust the bed to nozzle distance and the flow modifier, you will see this in the quality of your prints and the first layer sticking to the bed. So, the more (frequent) you need to tinker to get the print to stick or to print successfully and dimensionally correct, the bigger the change your nozzle has worn.</p>

CC BY-SA 4.0
2019-08-28T13:10:32.277Z
2019-09-04T17:27:31.377Z
2019-09-04T17:27:31.377Z
0scar
<p>You can check for shortened nozzle length using a set of feeler gauges to measure the gap from bed to nozzle. <a href="https://en.wikipedia.org/wiki/Feeler_gauge" rel="nofollow noreferrer">https://en.wikipedia.org/wiki/Feeler_gauge</a></p>

CC BY-SA 3.0
2017-07-06T05:56:11.960Z
A worn nozzle is not necessarily shortened. Also, this seems like a pretty unreliable method unless you (1) used feeler gauges when you first installed the nozzle, and remembered the exact gap between nozzle and bed (2) while using the nozzle, never changed anything to the set up like leveling the bed (3) the bed and nozzle were/are perfectly clean when measuring.
Tom van der Zanden
CC BY-SA 3.0
2017-07-05T17:33:01.373Z
2017-07-05T17:33:01.373Z
rkwadd
<p>I believe the little experiment made by E3D - the same link you provide - answers your question very well. Several points about wear can be found in this article. After printing only 250 grams of ColorFabb XT-CF20 (carbon fiber filament):</p>

<ul>
<li>The nozzle diameter had increased markedly</li>
<li>The inner walls of the orifice (opening) showed deep sharp ridges and grooves</li>
<li>The tip of the nozzle had become critically rounded, and shortened</li>
</ul>

<p>All of these symptoms were found repeatedly for standard brass nozzles.</p>

<p>In particular, I believe the last of these symptoms may be the one most easily identifiable without accurate measuring equipment (and without observing print quality).</p>

<p>With regards to reduction in print quality, these symptoms could be simulated by:</p>

<ul>
<li>Setting the nozzle diameter too big in your slicer</li>
<li>Leveling your bed too high (the rounded tip will also reduce the length of the tip)</li>
<li>Printing with a partial clog that interruptus normal filament flow (due to the grooves and ridges)</li>
</ul>

<p>Exactly what this will look like on your printed part is hard to predict, but I would assume you could see blobs, under-extrusion, poor layer adhesion, as well as an irregular surface finish of your top layers.</p>

CC BY-SA 4.0
2016-01-25T09:56:47.867Z
2019-08-28T12:33:37.610Z
2019-08-28T12:33:37.610Z
Tormod Haugene
<p><a href="https://e3d-online.com/blogs/news/are-abrasives-killing-your-nozzle" rel="nofollow noreferrer">E3D-Online</a> and <a href="http://makezine.com/2015/09/11/carbon-fiber-filament-ruins-nozzles/" rel="nofollow noreferrer">Make Magazine</a> have written about the potential damage printing carbon fiber and glow-in-the-dark filaments can do to your printer's nozzle.</p>
<p>What I can't seem to find is what clues or warning signs to be on the lookout for if your nozzle has taken a significant amount of wear. I've printed a few hundred grams of glow filament personally and have not noticed any change in print quality.</p>
<p>E3D says you may have &quot;unpredictable, erratic printing&quot; with a worn nozzle. Can anyone explain or provide examples of this and when a replacement is necessary?</p>

CC BY-SA 3.0
2016-01-22T07:27:54.493Z
Obviously, when you notice your print quality deteriorate... Don't fix it if it ain't broke.
Tom van der Zanden
CC BY-SA 3.0
2016-01-22T08:07:45.167Z
Somewhat off topic, but if you plan on printing *more* of such kind of filaments, consider getting a *hardened steel nozzle*
Tormod Haugene
CC BY-SA 3.0
2016-01-22T13:00:47.293Z
Where did it say that glow in the dark causes the same effects?
Eric Johnson
CC BY-SA 3.0
2016-01-22T14:20:49.430Z
It's fairly common knowledge. Depends on the particle size though, some GITDs are more abrasive than others.
Ryan Carlyle
CC BY-SA 3.0
2016-01-22T20:57:04.240Z
If you want to check directly (say, before doing a big or important print), I'd get a set of tiny drill bits (one of many sources: http://www.amazon.com/SE-Drill-Mini-Sizes-82615MD/dp/B0052Z9TJG). If the next size larger than should, fits through the nozzle, then it may be time to replace the nozzle. The bits are also useful in general...
TextGeek
<maintenance><carbon><nozzle>
How to identify nozzle wear?
TheNewHobbyist
# How to identify nozzle wear?

(Asked by: username_0 on 2016-01-22)

[E3D-Online](https://e3d-online.com/blogs/news/are-abrasives-killing-your-nozzle) and [Make Magazine](http://makezine.com/2015/09/11/carbon-fiber-filament-ruins-nozzles/) have written about the potential damage printing carbon fiber and glow-in-the-dark filaments can do to your printer's nozzle.

What I can't seem to find is what clues or warning signs to be on the lookout for if your nozzle has taken a significant amount of wear. I've printed a few hundred grams of glow filament personally and have not noticed any change in print quality.

E3D says you may have "unpredictable, erratic printing" with a worn nozzle. Can anyone explain or provide examples of this and when a replacement is necessary?

**Tags:** maintenance, carbon, nozzle
> **Comments:**
> **username_1**: Obviously, when you notice your print quality deteriorate... Don't fix it if it ain't broke.  
> **username_2**: Somewhat off topic, but if you plan on printing *more* of such kind of filaments, consider getting a *hardened steel nozzle*  
> **username_3**: Where did it say that glow in the dark causes the same effects?  
> **username_4**: It's fairly common knowledge. Depends on the particle size though, some GITDs are more abrasive than others.  
> **username_5**: If you want to check directly (say, before doing a big or important print), I'd get a set of tiny drill bits (one of many sources: http://www.amazon.com/SE-Drill-Mini-Sizes-82615MD/dp/B0052Z9TJG). If the next size larger than should, fits through the nozzle, then it may be time to replace the nozzle. The bits are also useful in general...  

---

## 5 answers

### Answer by username_2 on 2016-01-25. Score: 15 | Accepted answer

I believe the little experiment made by E3D - the same link you provide - answers your question very well. Several points about wear can be found in this article. After printing only 250 grams of ColorFabb XT-CF20 (carbon fiber filament):

* The nozzle diameter had increased markedly
* The inner walls of the orifice (opening) showed deep sharp ridges and grooves
* The tip of the nozzle had become critically rounded, and shortened

All of these symptoms were found repeatedly for standard brass nozzles.

In particular, I believe the last of these symptoms may be the one most easily identifiable without accurate measuring equipment (and without observing print quality).

With regards to reduction in print quality, these symptoms could be simulated by:

* Setting the nozzle diameter too big in your slicer
* Leveling your bed too high (the rounded tip will also reduce the length of the tip)
* Printing with a partial clog that interruptus normal filament flow (due to the grooves and ridges)

Exactly what this will look like on your printed part is hard to predict, but I would assume you could see blobs, under-extrusion, poor layer adhesion, as well as an irregular surface finish of your top layers.


---

### Answer by username_6 on 2017-05-13. Score: 8

One of the things I look for is if you pull the print head a good ways off the bed and have it extrude. It should just squirt plastic straight down. If it bends sharply in one direction, or even curls back on itself, then that is a sign of damage.


---

### Answer by username_7 on 2019-09-04. Score: 1

According tothe inner diameter doesn't change much, but, as said by @0scar, the nozzle shortens and at the end you get to the inner cavity.

Check the length and you are done.


---

### Answer by username_8 on 2019-08-28. Score: 1

**TL;DR** You could compare the nozzle to a similar new nozzle to look for wear.

---

The creators of the [Olsson Ruby Nozzle](https://olssonruby.com/anders-olsson-olsson-ruby/) have published some pictures of wear on brass, steel and hardened steel nozzles. From [their website](https://olssonruby.com/design-quality/) the following image is taken:

[![Nozzle wear](https://i.sstatic.net/drWLD.png)](https://i.sstatic.net/drWLD.png)

Depending on the amount of filament that is being printed, not only the internal dimensions, but also the outer dimension change considerably. This is clearly visible in the images. Comparing your nozzle to a similar new nozzle might give you an idea of the wear of your nozzle. It is expected that long before the nozzle reaches this state, you need to readjust the bed to nozzle distance and the flow modifier, you will see this in the quality of your prints and the first layer sticking to the bed. So, the more (frequent) you need to tinker to get the print to stick or to print successfully and dimensionally correct, the bigger the change your nozzle has worn.


---

### Answer by username_9 on 2017-07-05. Score: 0

You can check for shortened nozzle length using a set of feeler gauges to measure the gap from bed to nozzle. <https://en.wikipedia.org/wiki/Feeler_gauge>

> **Comments:**
> **username_1**: A worn nozzle is not necessarily shortened. Also, this seems like a pretty unreliable method unless you (1) used feeler gauges when you first installed the nozzle, and remembered the exact gap between nozzle and bed (2) while using the nozzle, never changed anything to the set up like leveling the bed (3) the bed and nozzle were/are perfectly clean when measuring.  

---

