There's another kind of screw extractor that's not twisted -- it's just a square bar with a little taper to it. You drill a hole that's smaller than the bar is corner-to-corner and drive the bar into the hole with a hammer and then you can put a wrench on it. I've had good luck with that kind of extractor and it'd be easier to make.
I have a lot of experience with stripped threads after restoring and customizing a '71 VeeWee. One of my favorite methods is the cold chisel trick, and I've come up with an improvement on the usual way it's done. The usual way is to take a *dull* cold chisel and strike at the edge of the screw head, but I prefer to cut a notch in the head with a sharp cold chisel, then stick a screwdriver in the notch and tap on that with a hammer.
That method works very well, works on screws that are in too tight for a screw extractor, and it's much faster.
For a 1-72 screw, though ... I guess you'd have to use a jeweler's screwdriver, and make a tiny cold chisel out of a heavy sewing needle or something, and you'll need a tiny little hammer.... I wonder what watch repairmen do with stripped screws. I wouldn't be surprised if they use my method; I think it would be more practical than itsy bitsy screw extractors that would be prone to breakage.
-Cougar Allen :{)
P.S. The advice above to send it back to the manufacturer is not bad advice, but that approach kind of takes the sport of it, doesn't it? Where's the challenge in that?
-Cougar Allen :{)
[This message has been edited by Cougar Allen (edited 24 January 1999).]