 Steel for toolmaking
Okay folks, Thomas is chomping at the bit to hammer some hard metal. But first, which metals are best for making what? While the answers to this question are manifold, some alloys are better than others for certain uses, in different circumstances, for different people. Here is an example. If I get hired to design and build a tool and die for the local whatever factory, after I figure out the BEST alloy for the job, I will order that stock, the heck with what it costs, my reputation as a tool and diemaker is on the line. But, what if I just want to make a drift, for enlarging a hole, that I punched in a hammer head? Can't I just grab a piece of that wicked hard stuff I got from under that car that just exploded in the driveway? Maybe, maybe not. Heres where it gets tricky(and where the disagreement will likely originate), First of all, what am I making the hammer head out of? Why does it matter? Depends on the constituents of the alloy. As Thomas pointed out, some alloys of steel are HARD even when hot, like red hot, even orange hot. So that means that whatever metal I force through that Hot Hard metal, needs some special qualities. Like toughness, and impact resistance, and ,(actual metallurgy term) Red-hardness. Red hardness is the ability of a metal to stay hard, when red hot. Back to the drift. Should I get out a tool steel catalog, determine the qualities I need, see which alloy most closely meets them, order the steel, pay the piper, pay the shipping(ouch), or should I use this piece of a jack hammer bit that is almost the right size? Since it is red hard, tough as all get out, impact resistant, and AIR HARDENING, I'm going for it. What does air hardening mean to me, right now? .(wheres Quenchcrack when you need him. Good luck in the hospital QC) ,After I take it out of the HOT chunk of steel I am working on, it air hardens again, all by itself, with no help from me. There may be 1000 ways to skin a cat, but some of them are easier or just better than others. Yes I know that early jack hammer bits may not be air hard. More to follow.
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