I just made one yesterday...after watching the (2) youtube videos... one titled "homemade wire stripper"
http://www.youtube.com/user/robraykino?blend=24&ob=5
and the other "franks wire stripping machine"
Both show a treadmill, after some modification turned wire crusher. There are no blades on either of the machines. Realizing i had access to an old treadmill, i thought i would give it a try. After looking around online, at the various motorized, or drill power strippers you can buy, i realized that attempting to make one first would be the right idea because they are either too expensive, or look a little flimsy, plus i like to make stuff.
An old treadmill is the perfect starting point. Obviously it has to have its own motor. But, if you can get your hands on one, more than half the work is done before you get started. The motor is mounted, leveled, wired, and set up to run one of the rollers already. Not to mention the most important thing being you have (2) perfectly round and long rollers that, if mounted right, will fit tight to each other. The tricky part is figuring out how to mount the second roller tight up against the first, with sufficient pressure to crush the wire you are going to be feeding through it. It took me around 4 hours to cut up the treadmill frame and piece it together to create the second roller mount, and i spent around $8.00 at a hardware store on some nuts and bolts. Once i got it put together it worked pretty well, although i do need to make a few modifications to it. The main one being to better secure the second roller mount and possibly add a spring on either side to create more pressure between the two rollers. This would allow me to raise the speed a bit higher and to feed the wires through without having to hold them back a bit to make sure the insulation is crushed. As of now i have to manually slow them feeding through the machine in order to ensure that the insulation is completely crushed. If i let them go on their own they just shoot right through the rollers without any crushing. I figure i've got another hour of tinkering before its right.
If you do attempt this sort of thing, definitely keep the treadmill controls/wiring intact. This way when your done with the modifying, there is no wiring of switches, speed controllers, or having to mount a drill. You simply plug the thing in, set the speed, and go. I also cut the piece used to mount the controls down and remounted them just above the rollers when i was done for easy use.
As far as tools, i used a Sawzall with a metal blade to cut up the frame (could use a hacksaw), and a cordless drill to make any holes needed for mounting the second roller. Also used an cordless impact driver on all the bolts (could use wrenches/ratchets instead).
Hopefully this helps...good luck.
