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bob -- A good tap and die set is very expensive, and very few people use all of the pieces. It might be wiser to buy just the pieces that you know you'll use, with extras of the ones you'll use the most, and leave the once-in-a-blue-moon stuff in the store until you actually need it. I would suggest buying only ground-thread spiral-point taps made of high-speed steel for general use. The spiral-point tap is intended to be machine driven, and the point is ground to push the chip down the hole ahead of the tap. Because of this, the tap works best if the hole is drilled all the way through the workpiece or, if blind, substantially deeper than the thread will be cut. On the other hand, the tap won't choke on its own chips . . . there's none of the half-a-turn-forward-and-half-a-turn-back rigmarole, just turn the tap into the hole. Good taps are available from any mill supply house, including the mail order houses such as J&L Industrial, MSC, and Travers Tool, but won't be found at any normal hardware store or tool truck. Brands to look for -- in no particular order -- would include Brubaker, Regal Beloit, OSG, Sosner, Reiff & Nestor, Uhring, Union-Butterfield, Hanson-Whitney, Morse, Greenfield, Emudge, and probably others that escape me at the moment. When it comes to dies, adjustable dies are better than non-adjustable BUT carry with them the possibility that a thread cut with a too-open die won't fit a tapped hole. I think all of the companies I mention for taps except Reiff & Nestor make dies. Unless you have good ones already, buy yourself good tap wrenches and die stocks while you're spending money. General Hardware's tap wrenches are superb for the price, but there are other good brands also. John
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