I have a few "Ace" taps made by Hanson. (large sizes, 5/8 to 7/8 NC). They do not say "HS" or "HSS" on them. They may be either high carbon steel taps, or perhaps they are HSS. Is there some easy test, like scratching them wiht a known high speed steel tool, that would let me tell. Thanks.
i- posted
16 years ago