I agree with the comments above, and would stress concerns with the side loading of an electric drill as well as lack of sufficient rpm's to do an acceptable job. Rather than go to all this trouble, I think I'd keep an eye out at yard sales, Craigslist, etc., to find a real cutoff saw. I have a 14" cutoff saw which rarely sees use anymore, since I've pretty much gone over to using thin cutoff (0.046") wheels on my handheld angle grinder. Sometimes I use a metal straightedge clamped to the work piece if having a straight finish cut is important. I will admit that it takes time and patience to do long cuts through larger than 1/4" plate, but I don't do enough of this type cutting to spend upwards of $1K for a decent plasma cutter.