<p>An X-Acto knife is probably going to be your best bet for the least cleanup of loose Styrofoam. Cut firmly but not so deep as to tear the Styrofoam.  Basically just the tip each pass and make multiple passes. It will be slow and tedious, but if you do it right, it won't be messy.</p>
<p><a href="https://i.sstatic.net/bzgJc.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/bzgJc.jpg" alt="X-Acto Knife" /></a></p>
<p>A faster method is to use a scroll saw with a vacuum attachment. This will create more pieces of Styrofoam but most of them should end up in the vacuum receptacle, reducing the amount of clean up. This will be a lot faster at the cost of a bit more clean up.</p>
<p><a href="https://i.sstatic.net/iFtJ3.jpg" rel="nofollow noreferrer"><img src="https://i.sstatic.net/iFtJ3.jpg" alt="scroll saw on a workbench" /></a></p>

CC BY-SA 3.0
2016-04-26T21:27:04.753Z
Scroll saw I think is a terrible choice for this since it would be moving up and down. Foam is light enough that the blade would be picking it up. Not to mention that cutting the foam could make it move around and expand just slightly as it is cut so that the blade would rip it more that cut it. This can largely depend on your foam choice as there are OODLES. Craft knife would be good as long as the blade is thicker that the work piece.
Matt
CC BY-SA 3.0
2016-04-26T21:35:43.373Z
@Matt It is what I have used in the past It moves so fast and the blade is small enough that the "sawdust" pieces are actually very small.  I have used it on several different types of styrofoam.  The only type I would be leary of trying would be the spongy type that never really hardens.
Chad
CC BY-SA 3.0
2016-04-26T21:37:46.230Z
Cant argue with experience then.
Matt
CC BY-SA 3.0
2016-04-26T23:06:35.683Z
Why don't you use a hot-wire cutter?
New Alexandria
CC BY-SA 3.0
2016-04-27T02:32:57.623Z
@NewAlexandria  Well I do not have one first.  I suspect that would leave the styrofoam blocks with a foul smell.  Maybe I am wrong and maybe that wont matter.  Not really sure.
Chad
CC BY-SA 3.0
2016-04-27T03:33:50.160Z
Styrofoam releases VOCs, so the odor doesn't stay around for long.
New Alexandria
CC BY-SA 4.0
2016-04-26T21:15:55.330Z
2022-10-26T14:11:33.093Z
2022-10-26T14:11:33.093Z
Chad
<p>They call them hot knives. Specifically designed for making clean cuts through styrofoam.</p>

CC BY-SA 4.0
2019-10-22T09:15:15.093Z
Is there anything we need to know about how to use this properly and safely? Does it work the same on all types of foam? More details could help expand this answer to be more useful!
Erica
CC BY-SA 4.0
2019-10-22T19:41:27.717Z
Hot knives is a little vague. From what I have seen styrofoam cutters actually use a wire, not really a knife at all.
rebusB
CC BY-SA 4.0
2019-10-21T18:42:18.090Z
2019-10-21T18:42:18.090Z
kkulpa
<p>Just take a lighter and slightly burn the area that was broken in half or cut and it will no longer shed. Be careful as it will burn and may drip on your skin.</p>

CC BY-SA 4.0
2018-12-10T00:23:49.913Z
This is useful, but not much of a help for making clean cuts in the first place.
Erica
CC BY-SA 4.0
2018-12-06T13:18:52.647Z
2018-12-08T19:43:31.680Z
2018-12-08T19:43:31.680Z
M.T.Ford
<blockquote>
<p>Is there a trick or special tool to make clean cuts without making a mess of little Styrofoam bits everywhere?</p>
</blockquote>
<p>Yes, it's called &quot;<a href="https://en.wikipedia.org/wiki/Hot-wire_foam_cutter" rel="nofollow noreferrer">hot-wire (foam) cutter</a>&quot; which can be bought starting at prices of about $20, or you can also <a href="https://www.youtube.com/results?search_query=hot+wire+foam+cutter" rel="nofollow noreferrer">make one yourself</a>.</p>
<p><img src="https://upload.wikimedia.org/wikipedia/commons/thumb/0/02/Styrofoam_Cutter_crop_color.JPG/320px-Styrofoam_Cutter_crop_color.JPG" alt="foam cutter" /></p>
<p>The hot wire melts the Styrofoam, releasing toxic fumes (styrene), so it's best to use it in a well-aerated room or outside. (See e.g. <a href="http://www.terragenesis.com/infopages/page173.html" rel="nofollow noreferrer">this link</a> for more safety advice.)</p>
<p>It will work on Styrofoam, but probably not very well on soft foams.</p>

CC BY-SA 4.0
2021-03-18T22:47:26.387Z
The YouTube video is gone.
ken
CC BY-SA 4.0
2016-04-26T22:24:14.817Z
2022-10-26T21:51:45.540Z
2022-10-26T21:51:45.540Z
Earthliŋ
<p>My roommate is a bit of a pack rat and has several old TV and computer monitor boxes with Styrofoam supports.</p>
<p>I am thinking of cutting the Styrofoam into little &quot;bricks&quot; and building a small house out of it.</p>
<p>Is there a trick or special tool to make clean cuts without making a mess of little Styrofoam bits everywhere?</p>

CC BY-SA 4.0
2021-03-19T10:45:25.800Z
Just a quick note: styrofoam bricks are often a problem to build with. Make sure you use the right adhesive or it will fall apart with time. Some people prefer cutting with hot wire, then sticking the still tacky blocks together an letting it set,but this requires lots of practice to get straight.
Gwyn
<styrofoam>
Is there a way to cleanly cut Styrofoam?
Jay
# Is there a way to cleanly cut Styrofoam?

(Asked by: username_0 on 2016-04-26)

My roommate is a bit of a pack rat and has several old TV and computer monitor boxes with Styrofoam supports.

I am thinking of cutting the Styrofoam into little "bricks" and building a small house out of it.

Is there a trick or special tool to make clean cuts without making a mess of little Styrofoam bits everywhere?

**Tags:** styrofoam

> **Comments:**
> **username_1**: Just a quick note: styrofoam bricks are often a problem to build with. Make sure you use the right adhesive or it will fall apart with time. Some people prefer cutting with hot wire, then sticking the still tacky blocks together an letting it set,but this requires lots of practice to get straight.  

---

## 4 answers

### Answer by username_9 on 2016-04-26. Score: 16 | Accepted answer

> Is there a trick or special tool to make clean cuts without making a mess of little Styrofoam bits everywhere?

Yes, it's called "[hot-wire (foam) cutter](https://en.wikipedia.org/wiki/Hot-wire_foam_cutter)" which can be bought starting at prices of about $20, or you can also [make one yourself](https://www.youtube.com/results?search_query=hot+wire+foam+cutter).

![foam cutter](https://upload.wikimedia.org/wikipedia/commons/thumb/0/02/Styrofoam_Cutter_crop_color.JPG/320px-Styrofoam_Cutter_crop_color.JPG)

The hot wire melts the Styrofoam, releasing toxic fumes (styrene), so it's best to use it in a well-aerated room or outside. (See e.g. [this link](http://www.terragenesis.com/infopages/page173.html) for more safety advice.)

It will work on Styrofoam, but probably not very well on soft foams.

> **Comments:**
> **username_10**: The YouTube video is gone.  

---

### Answer by username_2 on 2016-04-26. Score: 1

An X-Acto knife is probably going to be your best bet for the least cleanup of loose Styrofoam. Cut firmly but not so deep as to tear the Styrofoam. Basically just the tip each pass and make multiple passes. It will be slow and tedious, but if you do it right, it won't be messy.

[![X-Acto Knife](https://i.sstatic.net/bzgJc.jpg)](https://i.sstatic.net/bzgJc.jpg)

A faster method is to use a scroll saw with a vacuum attachment. This will create more pieces of Styrofoam but most of them should end up in the vacuum receptacle, reducing the amount of clean up. This will be a lot faster at the cost of a bit more clean up.

[![scroll saw on a workbench](https://i.sstatic.net/iFtJ3.jpg)](https://i.sstatic.net/iFtJ3.jpg)

> **Comments:**
> **username_3**: Scroll saw I think is a terrible choice for this since it would be moving up and down. Foam is light enough that the blade would be picking it up. Not to mention that cutting the foam could make it move around and expand just slightly as it is cut so that the blade would rip it more that cut it. This can largely depend on your foam choice as there are OODLES. Craft knife would be good as long as the blade is thicker that the work piece.  
> **username_2**: @username_3 It is what I have used in the past It moves so fast and the blade is small enough that the "sawdust" pieces are actually very small.  I have used it on several different types of styrofoam.  The only type I would be leary of trying would be the spongy type that never really hardens.  
> **username_3**: Cant argue with experience then.  
> **username_4**: Why don't you use a hot-wire cutter?  
> **username_2**: @username_4  Well I do not have one first.  I suspect that would leave the styrofoam blocks with a foul smell.  Maybe I am wrong and maybe that wont matter.  Not really sure.  
> **username_4**: Styrofoam releases VOCs, so the odor doesn't stay around for long.  

---

### Answer by username_5 on 2019-10-21. Score: 0

They call them hot knives. Specifically designed for making clean cuts through styrofoam.

> **Comments:**
> **username_6**: Is there anything we need to know about how to use this properly and safely? Does it work the same on all types of foam? More details could help expand this answer to be more useful!  
> **username_7**: Hot knives is a little vague. From what I have seen styrofoam cutters actually use a wire, not really a knife at all.  

---

### Answer by username_8 on 2018-12-06. Score: -2

Just take a lighter and slightly burn the area that was broken in half or cut and it will no longer shed. Be careful as it will burn and may drip on your skin.

> **Comments:**
> **username_6**: This is useful, but not much of a help for making clean cuts in the first place.  

---

