DIY Hot Wire Styrofoam Cutter Help (AC current)

Old 08-19-13, 11:03 AM
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DIY Hot Wire Styrofoam Cutter Help (AC current)

I'm trying to build my own hot wire cutter for cutting and shaping styrofoam. I have this AC cord that I stripped and split the two end wires:

I'm using a guitar string (the third from the top) for the wire that is to be heated.

I touched the two ends of the AC cord to the two ends of the guitar string, plugged it into an outlet, and nothing happened. What am I doing wrong?
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Old 08-19-13, 06:10 PM
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Welcome to the forums.

The principle is's called a hot wire cutter. You've probably already seen/used one.

In your picture you're using what looks like a 20vdc 1.8amp computer switching power supply. No good. When you connected the guitar string to it you created a dead short on it and it shut off.

You need a power supply that can run into a dead short or is good for several amps. In the videos below they show you what they use. The first video the guy uses a power supply with a dimmer for varying the voltage. Probably a good idea. The second guy uses an actual desktop computer supply which seems to work ok.

DIY Hot Wire Cutter - YouTube
DIY Foam Cutter on the Cheap - HOT WIRE! - YouTube

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