<p>Refraction of light is caused by changes in medium or angle of inflection. Any changes in medium will cause refraction, as such to be the most clear you would not want pockets of air. This means that if you are printing single layer 0% would work. The best appearance would most likely come from 100% infill as there would be no changes in the medium. The epoxy you linked to appears to smooth the surface, The smoother the surface, the clearer it will look. It is the same reason why you don't see clear textured mirrors or windows. </p>

CC BY-SA 3.0
2017-02-02T20:47:33.157Z
Welcome to the group @Faleroi! I feel like we have very similar points however I still wrote my answer as I felt that there was a need for a bit more expansion and supporting materials.
MakerModder
CC BY-SA 3.0
2017-02-02T17:40:18.420Z
2017-02-02T17:40:18.420Z
Falderol
<p>You are never going to get perfectly transparent prints, even if you were using real glass. Because of the way FDM prints, you would have fissures where the layers bond to each other. You can get good results if you use 0 or 100% infill <em>and</em> sand, then smooth the outside shell. If you are expecting optical quality, look somewhere else. However, I have successfully printed <em>very</em> nice diffusers for LED's with clear filament. </p>

CC BY-SA 3.0
2017-02-05T12:37:02.747Z
2017-02-06T00:56:30.257Z
2017-02-06T00:56:30.257Z
Richard Smith
<p>You will not get perfectly clear prints with FDM because of the mechanics of FDM printing there will always be tiny gaps. But, you can get pretty close as demonstrated by a <a href="https://learn.colorfabb.com/lets-make-something-clear/" rel="nofollow noreferrer">ColorFabb tutorial</a>.</p>

<p>A clear filament and printing an object at an elevated temperature (more than normal) and enough material to close the gaps (e.g. 110%) should be able to produce transparent prints, for example:</p>

<p><a href="https://i.sstatic.net/Kmn2Q.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/Kmn2Q.jpg" alt="Transparent printed parts"></a></p>

CC BY-SA 4.0
2018-09-18T12:35:56.317Z
2018-09-18T12:35:56.317Z
0scar
<p>First I would hedge your expectations.. I am very familiar with t-glase. It is very translucent but it is not clear and no amount of post treatment will make it 100% clear. Their example is the only exception where you have a simple print where it has only a single layer. By applying the clear coating they have normalized the wall and made the surface even. Thus no more light diffusion. </p>

<p>You could likely get the same effect with good sanding but good luck sanding a 1 wall thick print. Also note they do not show any solid parts. If they cannot get a solid part to look good and clear, then really you shouldn't expect to be able to. </p>

<p>Any infill will cause it to be non clear. Any extra shells will also create air pockets, lines, etc and make it non clear. If you really want clear, FDM is not the way to go. The only way I could imagine to print an item clear with FDM is to create a cast, then cast it with resin or glass.. </p>

<p>If you consider how the plastic is applied, you can see there is no real way make it 100% air pocket free.. See below,</p>

<p><a href="https://i.sstatic.net/8gd6j.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/8gd6j.jpg" alt="FDM"></a></p>

<p>Image taken from <a href="http://3devo.eu/guide-fdm-printable-plastics-3d-printing-filament/" rel="nofollow noreferrer">here</a>. </p>

<p>The best I can recommend for settings. Make your temp spot on. If you boil the material you will have less translucency. Play with over extruding (too much material) in a Limited amount. Might reduce gaps. I would also try to print in BIG THICK lines. Less lines, less diffusions.</p>

CC BY-SA 4.0
2018-09-18T12:26:31.200Z
You can get clear objects, even with FDM and multiple walls. ColorFabb has demonstrated it to [work](https://learn.colorfabb.com/lets-make-something-clear/).
0scar
CC BY-SA 3.0
2017-02-02T18:05:04.347Z
2017-02-02T20:50:34.313Z
2017-02-02T20:50:34.313Z
MakerModder
<p>I intend and would like to print a transparent hemisphere. I have a Taulman T-Glase clear 1.75 mm filament and I have XTC-3D.</p>

<p>You can read this interesting page, <a href="http://taulman3d.com/t-glase-optics.html" rel="nofollow noreferrer">Hacking t-glase to look more like glass!</a></p>

<p>First question, what kind of printing settings should I use? Should I go for a low infill percentage or a high one? Should I go for line or hexagon? I would say 5% line but perhaps there is a better setting.</p>

<p>Then, how should I use XTC-3D as mentioned on the above link? I'm a little bit confused how it can make the part more transparent.</p>

CC BY-SA 3.0
2017-02-02T11:43:48.670Z
Infill needs to be 0% or 100%, as I understand it. For a clear effect (rather than just allowing light to pass through diffuse) it is important to avoid any air-filament boundaries which don't follow the bulk geometry.
Sean Houlihane
CC BY-SA 3.0
2017-02-04T11:21:59.980Z
How big a nozzle do you have?
Gunslinger
CC BY-SA 3.0
2017-02-04T16:15:20.533Z
My nozzle is 1.75mm
gregoiregentil
CC BY-SA 3.0
2017-03-02T19:05:04.250Z
Your filament is 1.75mm, your nozzle is probably 0.40mm.

Or you're printing with a firehose.
Bryan B
CC BY-SA 3.0
2017-03-02T22:14:18.587Z
I have a Flashforge. This is correct. 0.4mm.
gregoiregentil
<filament><fdm><smoothing>
FDM: Clear=transparent part
gregoiregentil
# FDM: Clear=transparent part

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

I intend and would like to print a transparent hemisphere. I have a Taulman T-Glase clear 1.75 mm filament and I have XTC-3D.

You can read this interesting page, [Hacking t-glase to look more like glass!](http://taulman3d.com/t-glase-optics.html)

First question, what kind of printing settings should I use? Should I go for a low infill percentage or a high one? Should I go for line or hexagon? I would say 5% line but perhaps there is a better setting.

Then, how should I use XTC-3D as mentioned on the above link? I'm a little bit confused how it can make the part more transparent.

**Tags:** filament, fdm, smoothing
> **Comments:**
> **username_1**: Infill needs to be 0% or 100%, as I understand it. For a clear effect (rather than just allowing light to pass through diffuse) it is important to avoid any air-filament boundaries which don't follow the bulk geometry.  
> **username_2**: How big a nozzle do you have?  
> **username_0**: My nozzle is 1.75mm  
> **username_3**: Your filament is 1.75mm, your nozzle is probably 0.40mm.  Or you're printing with a firehose.  
> **username_0**: I have a Flashforge. This is correct. 0.4mm.  

---

## 4 answers

### Answer by username_5 on 2017-02-02. Score: 4 | Accepted answer

First I would hedge your expectations.. I am very familiar with t-glase. It is very translucent but it is not clear and no amount of post treatment will make it 100% clear. Their example is the only exception where you have a simple print where it has only a single layer. By applying the clear coating they have normalized the wall and made the surface even. Thus no more light diffusion.

You could likely get the same effect with good sanding but good luck sanding a 1 wall thick print. Also note they do not show any solid parts. If they cannot get a solid part to look good and clear, then really you shouldn't expect to be able to.

Any infill will cause it to be non clear. Any extra shells will also create air pockets, lines, etc and make it non clear. If you really want clear, FDM is not the way to go. The only way I could imagine to print an item clear with FDM is to create a cast, then cast it with resin or glass..

If you consider how the plastic is applied, you can see there is no real way make it 100% air pocket free.. See below,

[![FDM](https://i.sstatic.net/8gd6j.jpg)](https://i.sstatic.net/8gd6j.jpg)

Image taken from [here](http://3devo.eu/guide-fdm-printable-plastics-3d-printing-filament/).

The best I can recommend for settings. Make your temp spot on. If you boil the material you will have less translucency. Play with over extruding (too much material) in a Limited amount. Might reduce gaps. I would also try to print in BIG THICK lines. Less lines, less diffusions.

> **Comments:**
> **username_7**: You can get clear objects, even with FDM and multiple walls. ColorFabb has demonstrated it to [work](https://learn.colorfabb.com/lets-make-something-clear/).  

---

### Answer by username_4 on 2017-02-02. Score: 3

Refraction of light is caused by changes in medium or angle of inflection. Any changes in medium will cause refraction, as such to be the most clear you would not want pockets of air. This means that if you are printing single layer 0% would work. The best appearance would most likely come from 100% infill as there would be no changes in the medium. The epoxy you linked to appears to smooth the surface, The smoother the surface, the clearer it will look. It is the same reason why you don't see clear textured mirrors or windows.

> **Comments:**
> **username_5**: Welcome to the group @Faleroi! I feel like we have very similar points however I still wrote my answer as I felt that there was a need for a bit more expansion and supporting materials.  

---

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

You are never going to get perfectly transparent prints, even if you were using real glass. Because of the way FDM prints, you would have fissures where the layers bond to each other. You can get good results if you use 0 or 100% infill *and* sand, then smooth the outside shell. If you are expecting optical quality, look somewhere else. However, I have successfully printed *very* nice diffusers for LED's with clear filament.


---

### Answer by username_7 on 2018-09-18. Score: 0

You will not get perfectly clear prints with FDM because of the mechanics of FDM printing there will always be tiny gaps. But, you can get pretty close as demonstrated by a [ColorFabb tutorial](https://learn.colorfabb.com/lets-make-something-clear/).

A clear filament and printing an object at an elevated temperature (more than normal) and enough material to close the gaps (e.g. 110%) should be able to produce transparent prints, for example:

[![Transparent printed parts](https://i.sstatic.net/Kmn2Q.jpg)](https://i.sstatic.net/Kmn2Q.jpg)


---

