Yeah, I looked it up, thanks.... so you just let it cool in air after heating to 1725*F.... pretty easy, for sure.... I don't know if my local (hick town) supplier can get S7, or at what cost.... but it looks a good alternative, for sure....Bob
Mark, I use O1 drill rod, which machines nicely.... I then harden by coating with ivory bar soap (helps prevent it turning black), heating to cherry red (until it looses the ability to attract a magnet) with an acetylene torch set to a reducing flame (blue, but a little rich on acetylene), and then quenching in oil.... That makes it glass hard, but very brittle.... I then polish it again, and then hone the cutting edge with a very fine diamond file.... I then temper it in an oven at 480*F for 2 hours, or until I get an even brown colour…. This gives a good balance between keeping a nice edge and the toughness you require for a reamer so that it doesn't break (hopefully)....