<p>This is not a definitive answer (and has turned into a ramble), as I have not yet had to change my filament size. </p>

<p>However, initially, I would have thought that only the hotend and the hotend's nozzle would need to be changed, from one that can handle the 1.75 mm filament to 3 mm. If the extruder is spring loaded, then it should adjust itself to the thicker filament, without a problem. If not, then you may have to do a slight manual adjustment.</p>

<p>However, after doing some further reading, there may be other factors that need to be considered, such as:</p>

<ul>
<li>Extruder gearing;</li>
<li>Melt time (which would imply a different feed rate)</li>
</ul>

<p>It could be worth having a close look at the aperture of your hotend. If, in the unlikely situation, it looks as if the hotend would accept 3 mm (or if you could remove the lining so that it can), you <em>may</em> not need to actually change any hardware, but instead just try tweeking the <strong>feedrate</strong> in the software, because as your nozzle is less than the width of the filament anyway, then it will be fine for both 1.75 mm <em>and</em> 3 mm. A 3 mm filament would require more heating, and therefore a slower feedrate than a 1.75 mm feedrate. Once the filament has melted, so long as the pressure from the extruder is sufficient, then the molten filament should come out of the nozzle. However, this may be a less than satisafctory method and result in some dubious prints.</p>

<p>There is an interesting thread on the RepRap wiki, <a href="http://forums.reprap.org/read.php?1,128719,page=1" rel="nofollow noreferrer">1.75mm Filament vs 3mm Filament</a>, that discusses most of the points above.</p>

<p>It should be noted that the advantages of 3 mm filament has over 1.75 mm are that it is:</p>

<ul>
<li>cheaper</li>
<li>stiffer (less flexible) and thus "easier" to push through the hotend.</li>
</ul>

<p>As an aside, one interesting point raised in the thread, is that maybe a smaller extruder can be used, for the narrower 1.75 mm filament, thus resulting in a lighter print head. I am not sure how true that is.</p>

<p>This article, <a href="http://hackaday.com/2015/10/17/converting-a-3d-printer-from-3mm-to-1-75mm/" rel="nofollow noreferrer">Converting a 3D printer from 3mm to 1.75mm</a>, does the reverse of what you want, and comes with a <a href="https://www.youtube.com/watch?v=UcMw-3RizIw" rel="nofollow noreferrer">video</a>. It states that, as you have already found, that the hotend needs to be changed:</p>

<blockquote>
  <p>The printer [Thomas] is changing out to accept 1.75mm is the Lulzbot
  Mini, one of the most popular printers that would ever need this
  modification. The only required materials is a new hot end suitable
  for 1.75mm filament, a 4mm drill, and a few wrenches and allen keys.
  It would be a smart idea to get a hot end that uses the same
  thermistor as the old one, but that’s not a deal-breaker as the
  problem can be fixed in the firmware.</p>
</blockquote>

<p>Alternatively, you could leave your printer as it is and use a <a href="http://www.thingiverse.com/thing:72336" rel="nofollow noreferrer">3mm to 1.75mm filament converter</a>, which may be a bit of overkill for just one reel of filament<sup>1</sup>.</p>

<h3>The bottomline</h3>

<p>To be honest, is it worth the hassle, time and expense of having to modify and re-calibrate your printer (or worst case, change the model of the printer), just for the price of a reel of filament (assuming that you did not bulk purchase a bunch of reels)? It may be better to stick to one filament size (i.e. your original size) for all of your projects, and so resell the reel of 3 mm and stick with the 1.75 mm printer and buy the correct filament<sup>2</sup>.</p>

<hr>

<p><sup>1</sup> See also <a href="https://3dprinting.stackexchange.com/questions/38/conversion-of-3mm-abs-filament-to-1-75mm">Conversion of 3mm ABS filament to 1.75mm</a></p>

<p><sup>2</sup> See also <a href="https://3dprinting.stackexchange.com/questions/38/conversion-of-3mm-abs-filament-to-1-75mm#answer-42">Tom's answer</a> to <a href="https://3dprinting.stackexchange.com/questions/38/conversion-of-3mm-abs-filament-to-1-75mm">Conversion of 3mm ABS filament to 1.75mm</a></p>

<p>See also <a href="https://3dprinting.stackexchange.com/questions/269/can-1-75mm-filament-be-used-in-a-printer-that-takes-3mm-filament">Can 1.75mm filament be used in a printer that takes 3mm filament?</a></p>

CC BY-SA 3.0
2017-02-04T03:01:11.840Z
Thank you for taking your time to actually write it like a literature review, even. I'll still need to experiment on it. I've actually upvote your answer nonetheless, but my reputation is too low to show an effect. I am looking into changing the hot end first. Wish me luck.
Alvin Herawan
CC BY-SA 3.0
2017-02-04T03:31:37.653Z
@AlvinHerawan - Not a problem, it was interesting for me too. Yes, you need 15 rep points to upvote. I've just given you 5. Remember to revisit this post when you have enough rep... Good luck! :-)
Greenonline
CC BY-SA 4.0
2022-02-23T15:15:49.323Z
The extruder hobbel bolt (or whatever is used) is usually shaped round to better grip the filament. The radius of the teeth won't grip 3 mm filament at all, therefore it will likely skip or skid very easily, especially given the increased grip required for 3 mm filament. 1.75 <> 3 mm is a complete overhaul of anything related to the extrusion path. I did it.
FarO
CC BY-SA 4.0
2022-02-23T16:36:32.837Z
@FarO - You should post that as an answer... it's useful info and should have more prominence than just a comment... I'll upvote it.
Greenonline
CC BY-SA 4.0
2022-02-24T08:27:22.497Z
@Greenonline I think that was I found here on 3dp.SE back when I thought about the same!
FarO
CC BY-SA 3.0
2017-02-04T02:09:08.900Z
2017-02-04T03:33:41.773Z
2017-04-13T13:00:58.447Z
Greenonline
<p>Well... Usually when one buys a 30 dollar roll of plastic they don't replace a 1k machine.. </p>

<p>That said you can change out the extruder. The extruder is what matters. So if you have a Prusa i3, you can go and buy say a e3d hot end that is made for 3mm. </p>

<p>Usually we see 3mm on Bowden printers like the Ultimaker. Everyone else has moved to 1.8. </p>

<p>I would just toss this on craigslist and get the correct plastic.</p>

CC BY-SA 3.0
2017-02-06T20:43:59.823Z
Yeah, agree with you ... I was just curious with this 3mm size. Of course I'd rather toss the whole spool ... perhaps find a use for it somehow, someday.
Alvin Herawan
CC BY-SA 3.0
2017-02-05T21:30:54.033Z
2017-02-05T21:30:54.033Z
MakerModder
<p>Any modern and decent drive gear (single or dual) is shaped round (concave) to better grip the filament.</p>
<p><a href="https://i.sstatic.net/p8csV.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/p8csV.jpg" alt="enter image description here" /></a></p>
<p>Some are flat, but only the cheapest and least performing ones.</p>
<p><a href="https://i.sstatic.net/nwrob.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/nwrob.jpg" alt="enter image description here" /></a></p>
<p>(from <a href="https://reprap.org/wiki/Drive-gear" rel="nofollow noreferrer">Reprap wiki</a>)</p>
<p>The concave part designed for 1.75 mm filament will be too small to accept 3 mm filament, it will grip it so weakly that it will skip or skid very easily, especially given the increased grip required for 3 mm filament.</p>
<p>1.75 &lt;-&gt; 3 mm is a complete overhaul of anything related to the extrusion path. I did it so I know...</p>

CC BY-SA 4.0
2022-02-24T08:37:40.763Z
2022-02-24T08:37:40.763Z
FarO
<p>Late to the party here but I am doing this exact thing. I stupidly bought like a dozen rolls of 3mm filament for about $6 a Kg. I think trying the switch should be fun...but I have 7 printers so its no big deal to tinker on one of them.</p>
<p>What you need to do is modify the extruder. I have done this successfully using the crappy plastic extruders which come with most budget printers. You have to drill out the filament path to fit the 3 mm filament. It does get a little tricky to get the filament to run through nicely.</p>
<p>You actually <strong>do not</strong> need to modify your hot end other than your Bowden tube and your nozzle. Regular Bowden tube is 2 mm ID and 4 mm OD, so you just order 3 mm ID and 4 mm OD tube. Please note that this plan <strong>will not</strong> work for an all metal 1.75 mm hotend.</p>
<p>For the nozzle you can often find 3 mm compatible nozzles. Unfortunately they don't seem to be made for the MK10 hotend. So I simply ordered big ole 1 mm nozzles made for 1.75 mm and I am going to drill out the back for the 2.85 mm (3 mm) filament.</p>
<p>I am excited to see how this all works. You can get some really good deals on 3 mm filament <em>and</em> I suspect that it will actually work much better for things like TPU since it is significantly more rigid due to the increased diameter!</p>

CC BY-SA 4.0
2022-02-22T23:51:27.220Z
2022-02-23T02:06:29.423Z
2022-02-23T02:06:29.423Z
brad
<p>I'm not really sure if I'm asking the right question here, but I just made a noob mistake of buying 3 mm filaments instead of 1.75 mm. I have a Makerbot Replicator 2 which I've been using and so far it is pulling in 1.75 mm quite well.</p>
<p>Is there any way I can still make use the 3 mm filaments, or do I need to use the filaments on different models? If it is the latter, which particular model is able to pull in 3 mm filament well?</p>

CC BY-SA 3.0
2017-02-03T14:36:53.090Z
Alvin, you will need to research. I know of no comparison site which lists printers based on filament diameter.
Davo
CC BY-SA 3.0
2017-02-03T14:53:43.630Z
Thanks, Davo. So far, what I have learnt is that I need to mod the extruder and nozzle to be able to use the 3mm filaments.
Alvin Herawan
CC BY-SA 3.0
2017-02-03T15:58:05.297Z
Research also if modifying the extruder will void your warranty.
Davo
CC BY-SA 3.0
2017-02-04T02:02:53.540Z
The extruder shouldn't need to be changed, I would have thought that just the hotend (and maybe the nozzle) would need to be changed.
Greenonline
CC BY-SA 3.0
2017-02-04T07:38:03.130Z
The title you have chosen for your question is not very good. Asking for a list of printer models (or even just a recommendation for a single printer) does not make a good stack exchange question, because an answer would need to be unreasonably long, or would be opinion-based because we'd need to recommend one particular printer over all the others. Perhaps you can edit the title (and the body of the question) to focus on whether/how you can use 3mm filament in your printer and how you can tell whether a printer accepts 3mm filament.
Tom van der Zanden
CC BY-SA 3.0
2017-02-04T12:26:41.817Z
Return the filament (or sell it) and buy the proper diameter. Save yourself a lot of trouble.
Gunslinger
<filament><extruder>
How to Make Use of 3 mm Filaments?
Alvin Herawan
# How to Make Use of 3 mm Filaments?

(Asked by: username_0 on 2017-02-03)

I'm not really sure if I'm asking the right question here, but I just made a noob mistake of buying 3 mm filaments instead of 1.75 mm. I have a Makerbot Replicator 2 which I've been using and so far it is pulling in 1.75 mm quite well.

Is there any way I can still make use the 3 mm filaments, or do I need to use the filaments on different models? If it is the latter, which particular model is able to pull in 3 mm filament well?

**Tags:** filament, extruder
> **Comments:**
> **username_1**: Alvin, you will need to research. I know of no comparison site which lists printers based on filament diameter.  
> **username_0**: Thanks, Davo. So far, what I have learnt is that I need to mod the extruder and nozzle to be able to use the 3mm filaments.  
> **username_1**: Research also if modifying the extruder will void your warranty.  
> **username_2**: The extruder shouldn't need to be changed, I would have thought that just the hotend (and maybe the nozzle) would need to be changed.  
> **username_3**: The title you have chosen for your question is not very good. Asking for a list of printer models (or even just a recommendation for a single printer) does not make a good stack exchange question, because an answer would need to be unreasonably long, or would be opinion-based because we'd need to recommend one particular printer over all the others. Perhaps you can edit the title (and the body of the question) to focus on whether/how you can use 3mm filament in your printer and how you can tell whether a printer accepts 3mm filament.  
> **username_4**: Return the filament (or sell it) and buy the proper diameter. Save yourself a lot of trouble.  

---

## 4 answers

### Answer by username_2 on 2017-02-04. Score: 2 | Accepted answer

This is not a definitive answer (and has turned into a ramble), as I have not yet had to change my filament size.

However, initially, I would have thought that only the hotend and the hotend's nozzle would need to be changed, from one that can handle the 1.75 mm filament to 3 mm. If the extruder is spring loaded, then it should adjust itself to the thicker filament, without a problem. If not, then you may have to do a slight manual adjustment.

However, after doing some further reading, there may be other factors that need to be considered, such as:

* Extruder gearing;
* Melt time (which would imply a different feed rate)

It could be worth having a close look at the aperture of your hotend. If, in the unlikely situation, it looks as if the hotend would accept 3 mm (or if you could remove the lining so that it can), you *may* not need to actually change any hardware, but instead just try tweeking the **feedrate** in the software, because as your nozzle is less than the width of the filament anyway, then it will be fine for both 1.75 mm *and* 3 mm. A 3 mm filament would require more heating, and therefore a slower feedrate than a 1.75 mm feedrate. Once the filament has melted, so long as the pressure from the extruder is sufficient, then the molten filament should come out of the nozzle. However, this may be a less than satisafctory method and result in some dubious prints.

There is an interesting thread on the RepRap wiki, [1.75mm Filament vs 3mm Filament](http://forums.reprap.org/read.php?1,128719,page=1), that discusses most of the points above.

It should be noted that the advantages of 3 mm filament has over 1.75 mm are that it is:

* cheaper
* stiffer (less flexible) and thus "easier" to push through the hotend.

As an aside, one interesting point raised in the thread, is that maybe a smaller extruder can be used, for the narrower 1.75 mm filament, thus resulting in a lighter print head. I am not sure how true that is.

This article, [Converting a 3D printer from 3mm to 1.75mm](http://hackaday.com/2015/10/17/converting-a-3d-printer-from-3mm-to-1-75mm/), does the reverse of what you want, and comes with a [video](https://www.youtube.com/watch?v=UcMw-3RizIw). It states that, as you have already found, that the hotend needs to be changed:

> The printer [Thomas] is changing out to accept 1.75mm is the Lulzbot
> Mini, one of the most popular printers that would ever need this
> modification. The only required materials is a new hot end suitable
> for 1.75mm filament, a 4mm drill, and a few wrenches and allen keys.
> It would be a smart idea to get a hot end that uses the same
> thermistor as the old one, but that’s not a deal-breaker as the
> problem can be fixed in the firmware.

Alternatively, you could leave your printer as it is and use a [3mm to 1.75mm filament converter](http://www.thingiverse.com/thing:72336), which may be a bit of overkill for just one reel of filament1.

### The bottomline

To be honest, is it worth the hassle, time and expense of having to modify and re-calibrate your printer (or worst case, change the model of the printer), just for the price of a reel of filament (assuming that you did not bulk purchase a bunch of reels)? It may be better to stick to one filament size (i.e. your original size) for all of your projects, and so resell the reel of 3 mm and stick with the 1.75 mm printer and buy the correct filament2.

---

1 See also [Conversion of 3mm ABS filament to 1.75mm](https://3dprinting.stackexchange.com/questions/38/conversion-of-3mm-abs-filament-to-1-75mm)

2 See also [Tom's answer](https://3dprinting.stackexchange.com/questions/38/conversion-of-3mm-abs-filament-to-1-75mm#answer-42) to [Conversion of 3mm ABS filament to 1.75mm](https://3dprinting.stackexchange.com/questions/38/conversion-of-3mm-abs-filament-to-1-75mm)

See also [Can 1.75mm filament be used in a printer that takes 3mm filament?](https://3dprinting.stackexchange.com/questions/269/can-1-75mm-filament-be-used-in-a-printer-that-takes-3mm-filament)

> **Comments:**
> **username_0**: Thank you for taking your time to actually write it like a literature review, even. I'll still need to experiment on it. I've actually upvote your answer nonetheless, but my reputation is too low to show an effect. I am looking into changing the hot end first. Wish me luck.  
> **username_2**: @AlvinHerawan - Not a problem, it was interesting for me too. Yes, you need 15 rep points to upvote. I've just given you 5. Remember to revisit this post when you have enough rep... Good luck! :-)  
> **username_5**: The extruder hobbel bolt (or whatever is used) is usually shaped round to better grip the filament. The radius of the teeth won't grip 3 mm filament at all, therefore it will likely skip or skid very easily, especially given the increased grip required for 3 mm filament. 1.75 <> 3 mm is a complete overhaul of anything related to the extrusion path. I did it.  
> **username_2**: @FarO - You should post that as an answer... it's useful info and should have more prominence than just a comment... I'll upvote it.  
> **username_5**: @Greenonline I think that was I found here on 3dp.SE back when I thought about the same!  

---

### Answer by username_6 on 2017-02-05. Score: 2

Well... Usually when one buys a 30 dollar roll of plastic they don't replace a 1k machine..

That said you can change out the extruder. The extruder is what matters. So if you have a Prusa i3, you can go and buy say a e3d hot end that is made for 3mm.

Usually we see 3mm on Bowden printers like the Ultimaker. Everyone else has moved to 1.8.

I would just toss this on craigslist and get the correct plastic.

> **Comments:**
> **username_0**: Yeah, agree with you ... I was just curious with this 3mm size. Of course I'd rather toss the whole spool ... perhaps find a use for it somehow, someday.  

---

### Answer by username_5 on 2022-02-24. Score: 0

Any modern and decent drive gear (single or dual) is shaped round (concave) to better grip the filament.

[![enter image description here](https://i.sstatic.net/p8csV.jpg)](https://i.sstatic.net/p8csV.jpg)

Some are flat, but only the cheapest and least performing ones.

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

(from [Reprap wiki](https://reprap.org/wiki/Drive-gear))

The concave part designed for 1.75 mm filament will be too small to accept 3 mm filament, it will grip it so weakly that it will skip or skid very easily, especially given the increased grip required for 3 mm filament.

1.75 <-> 3 mm is a complete overhaul of anything related to the extrusion path. I did it so I know...


---

### Answer by username_7 on 2022-02-22. Score: 0

Late to the party here but I am doing this exact thing. I stupidly bought like a dozen rolls of 3mm filament for about $6 a Kg. I think trying the switch should be fun...but I have 7 printers so its no big deal to tinker on one of them.

What you need to do is modify the extruder. I have done this successfully using the crappy plastic extruders which come with most budget printers. You have to drill out the filament path to fit the 3 mm filament. It does get a little tricky to get the filament to run through nicely.

You actually **do not** need to modify your hot end other than your Bowden tube and your nozzle. Regular Bowden tube is 2 mm ID and 4 mm OD, so you just order 3 mm ID and 4 mm OD tube. Please note that this plan **will not** work for an all metal 1.75 mm hotend.

For the nozzle you can often find 3 mm compatible nozzles. Unfortunately they don't seem to be made for the MK10 hotend. So I simply ordered big ole 1 mm nozzles made for 1.75 mm and I am going to drill out the back for the 2.85 mm (3 mm) filament.

I am excited to see how this all works. You can get some really good deals on 3 mm filament *and* I suspect that it will actually work much better for things like TPU since it is significantly more rigid due to the increased diameter!


---

