Hand Tools Archive

Re: Question for the Metalworkers

david weaver
It's something you see only by accident (and then maybe in anger and curiosity).

This is my first experience with something that air hardens. It taught me a lesson. Since this is stainless steel, I will probably cool it with water. A "professional" and not a hack would have some type of machine to drill this slot at slow speed with liquid or high speed with liquid - something that would keep the temperature low.

XHP has a wonderful characteristic in that you can heat it above carbon steel's quench temperature, but it's not absurdly high and you can get there quick and quench. It also has the wonderful characteristic of tempering at cupcake temperature in the oven more or less.

What I failed to realize is that just because my two end points are similar, it doesn't mean that I can assume that I can just anneal the metal easily or heat it to blue and get a good result. Rather, what it does is:
* temper at high hardness at a low temperature (unlike HSS)
* lose very little hardness at accidental edge burning or over-tempering (unlike carbon steel)

It's also like grease through wood, or kryptonite to an uncooled drill bit.

As a professor of mine used to say in college, "learning hurts".

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