Does anyone know if HF tap and dies are HHS? Which ones are the good ones and what alloys are they using?
I have the 41452 set of metric taps and dies. They are claimed to be "alloy steel" Ti coated. The dies that I have used have proved to be adequate to cut threads on mild steel. I bought the set for the larger metric thread sizes that are included; I was in a situation were I needed the dies pronto and did not have time to order one from the supply house. It was on sale and so I got a whole set for less than ordering the 22mm die and paying for expedited shipping. I have been pleased so far with the set. I think it may be equivalent to the Asian manufactured high speed steel line sold by MSC, ENCO. Travers, Victor, etc. I always liked the made in Poland and Yugoslavia taps and dies that the supply houses sold. So far I have not been able to tell the difference between the HF set and the Chinese stuff.
I don't think I would trust the carbon steel set or the low end (by HF standards) sets.
Geoff Morgan