I'm not going to go into too much detail on building a hot wire foam cutter here. There are tons of great instructables and videos already.  I am going to show you how my laziness and impatience in building one paid off with a new material to use that will allow you to bend the wire into shapes to cut with.

If you like this, check out my other instructables here.

I also made a video podcast of this below.

Step 1: the wire

So when I was building my foam cutter, I did not want to wait for a roll of nichrome wire to arrive in the mail.  I started looking around my house for something else I could try out.  I know that stainless steel conducts electricity but not very well and I happened to have some 1/16th tig wire in my shop.  This stuff is so handy to have around and I have used it for many projects in the past, most notably my make your own springs in seconds instructable. I decided to try it out and it works.  You sometimes have to adjust the resistance by extending the wire longer because this is pretty hard on the power supply.  I can tell if the resistance is too low because the power supply sounds like a weightlifter going for the world record.  The wire does not get red hot but will cut foam easily enough.  The best part about this is because it doesn't get red hot it can easily hold any shape you bend it into.
Great, neat, and I bet it would also bend Acrylic, in witch case, you'll have a great Cutting and Moulding Platform, right there! <br>Again, the Stainless Steel is a great idea, because nicrome wire is brittle and won't allow for hand moulding, so you can mould Acrylic plate in some crazy ways! :)
I keep a 12v car battery in my shop for this type work, also for testing 12v systems. A 12v battery will provide PLENTY of amps. Then I recharge it with a standard battery charger.
cool stuff man! I like the use of the Tig wire, I'll have to try it! If you need a hand on the scientific math stuff, hit me up!<br><br>and I was thinking it would be neat to use the tig wire as a stamp too. like if you want the same shape all the time you could lay the foam flat on a table and have a hand held foam cutter and 'stamp' it down on to the foam
I want to know about transformer amp , volt , watt for 14 gauge heat resistance wire.<br>
Hi,<br>this is a great tool you have done, I have tried to make one, I am using a 12v 2A dc power suppl, and as the cutter i used guitar string but that did not work. Then I switched to the coil wire inside a soldering iron, and it works cool. But the problem is every now and then it breaks.<br><br>Could you please tell me what would be the resistance of your wire, and say for a piece of 10 inches, and what power supply are you using with that?<br><br>I would also like to know that if I use a smaller piece of the wire, should there be any power regulation that is to be done?<br><br>Thank you.
I don't get too scientific about it. If it doesn't heat up, I slide the clip to shorten the wire. If my power supply sounds like it's in pain, I lengthen the wire. I did get a reading of .8 ohms for aprox 10 inches. My power supply is an old battery charger that is 6 amps.
Great instructable just what I am looking to do. Thanks.

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Bio: I have had a few careers so far, soldier, school teacher, arborist, millwright. I love change and I love learning.
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