Heat treating larger pieces in the forge

[jmccarth]

I think I'm going to send out the 420ss and try the rest on my own in my forge. My home forge is a large coal forge with a vulcan fire pot It shouldn't be a problem bringing the steel up to temp. Does anyone have experience juging temp to a close tolerance in a coal forge. My plan is to use heat crayons for heat and temper. The sow block is O1 and the Flat dies I built are 4140 any sugestions on temper heat?

[patrick]

The die holders of most hammers are not heat treated, in fact, on most mechanical hammers they are cast iron. There is no need to heat treat the die holder, regardless of steel type. The dies themselves should be heat treated, but sharp corners in the dovetails will act as serious stress risers and can result in cracks either during quenching or in service. If such a sharp corner is absoultly necessary, it should be machined in after heat treat is complete. I would recommend that you look into having the heat treat work done at American Steel Treating in Perrysburg OH. They used to do knives for me and for any job under 20 lbs the price was $20. That was about 10-12 years ago, but I still doubt they would chage $100 to do your dies since they will batch them with other work to make a furnace load. There is no advantage to using induction heating on your dies since they are not of uniform cross section (round or square). Custom coils would have to made for the dies, and there is just no reason to do that.

Patrick