Here is a little two-part video series I worked up for building your own low-cost, safe, and reliable power supply for heating your hot-wire cutting equipment. The total cost for this unit was about $35.

PART 1

PART 2

Here is the parts list for items used in this build:

MUST HAVE ITEMS:

From Radio Shack...

Enclosure (8"x6"x3", #270-1809)
Transformer (25.2v, 2 amp, #273-1512B)
Bind Post (#274-661)
Banana Plugs (#274-721)

From Lowes...

Lutron Dimmer Switch (#D-600PH-DK)
Nuts and bolts, or rivets for mounting components

Additionally...

An old AC power cord (2 or 3 prong) with appropriate plug

Optional Parts I Recommend (from Radio Shack)

Fuse Holder (#270-364)
Fuse (250 volt, 2 amp, #270-1023)
120 volt Neon Lamp (#272-0704)

For more information on this project, tune in to TheCrashCast podcast (in iTunes, or at www.TheCrashCast.com), episode #82 (scheduled for release 8/22/10).