There are lots of videos on YouTube about cutting Styrofoam with a hot wire. I’m not going to get too technical here, but the key is you need a piece of thin nichrome wire.
I could not find this at the local hardware store. We used to buy it when I was a kid, to make the coils for setting off model rockets. But this wire is also used as the coils and resistance heaters in a hairdryer, or in my case, a Wagner heat gun with burned up electronics. I killed the chips taking all the stickers off of brand new huffy.
I used the thick main heater coil and an alligator clip, as a ghetto rheostat, to adjust the heat of the hot wire. This one works fine with the clip on the third coil, but this will vary with the gauge and length of the hotwire you use.
It runs off a small car battery, through my rheostat. The hot wire itself came from a thinner coil of wire inside the heater. Here’s my ghetto rheostat:
This coil will get hot in use, so don’t let it rest on the battery case, or it will melt the plastic. Ask me how I know…
I made this little wooden compass to support the hotwire and cut circles. Of course it will not encompass a 4’x8’ sheet, so after I proved the device on this corner, I had to rough it out first, to finish it.
If you decide to do this hot wire cutting business, it is best to make the frame as stiff as possible to keep tension on the hot wire. I was able to easily put a nice taper on the cut, but without a good constant tension on the wire, you can get some waviness quite easily.
I could adjust the heat up and down by moving the alligator clip but I tend to run the hot wire a little cool and travel slowly. You can run it hot and travel fast but that means you will make mistakes more quickly as well.
Also the hotter the wire is, the more fumes this process will release, and my final advice to you is do not breathe in the fumes from cutting the plastic.
They are Toxic . Do this outdoors where there’s lots of air, and even use a fan in still air.
I could not find this at the local hardware store. We used to buy it when I was a kid, to make the coils for setting off model rockets. But this wire is also used as the coils and resistance heaters in a hairdryer, or in my case, a Wagner heat gun with burned up electronics. I killed the chips taking all the stickers off of brand new huffy.
I used the thick main heater coil and an alligator clip, as a ghetto rheostat, to adjust the heat of the hot wire. This one works fine with the clip on the third coil, but this will vary with the gauge and length of the hotwire you use.
It runs off a small car battery, through my rheostat. The hot wire itself came from a thinner coil of wire inside the heater. Here’s my ghetto rheostat:
This coil will get hot in use, so don’t let it rest on the battery case, or it will melt the plastic. Ask me how I know…
I made this little wooden compass to support the hotwire and cut circles. Of course it will not encompass a 4’x8’ sheet, so after I proved the device on this corner, I had to rough it out first, to finish it.
If you decide to do this hot wire cutting business, it is best to make the frame as stiff as possible to keep tension on the hot wire. I was able to easily put a nice taper on the cut, but without a good constant tension on the wire, you can get some waviness quite easily.
I could adjust the heat up and down by moving the alligator clip but I tend to run the hot wire a little cool and travel slowly. You can run it hot and travel fast but that means you will make mistakes more quickly as well.
Also the hotter the wire is, the more fumes this process will release, and my final advice to you is do not breathe in the fumes from cutting the plastic.
They are Toxic . Do this outdoors where there’s lots of air, and even use a fan in still air.
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