Are you talking about the feather billets, or the cutting tool? The first time I made a cutter, I forge it to shape on the air hammer, then went through heat treating it, thinking that would help it hold up. NOT! After that I just forge to shape on the air hammer, let the cutter cool on the shop floor, then finish it out on the grinder and use/destroy it.
Then make another when the need arises. I don't make a lot of feather pattern simply because my press has such a short "throw".....between the room needed for the cutter and the billet, the longest feather billet I can make is about 4". Hopefully that will all change soon, as I'm in the process of acquiring a much larger press, with much more "throw".