This is unfortunately an impractical coil for us. We can not oil quench inside for a number of reasons. Plus with that design if you bump the main case you will get shocked.
We have supplies to make more but haven’t had the need in a while.
Put the blade in the forge with the doors open, moving it back and forth under one of the burners.
Placing the blade edge up, especially if placed under a burner, will differencially heat the metal because the edge is thinner than the spine and will heat more quickly. Leaving the doors open will increase that differential, allowing the edge to heat faster than the spine, thereby allowing the differential quench you’re looking for.
Starting with a cold forge (or turning it off for 5-10 mins before restarting for the quenching heat) will allow the internal parts of the forge to cool down and make the differential even higher yet.
Another option is to fully heat the blade, quench it, then temper the spine to a using a MAPP torch, drawing a straw yellow color about halfway across the width of the blade. This gets a similar result of a hardened edge and a tempered, softer spine.
I wasn’t even thinking about oil quenching, mostly about heating only the edge for easier beveling. Thanks for letting me know about the electrocution thing though
It doesn’t work like that. The heat will diffuse from the hot area to the cold before you will see any difference in the ability to move the metal. Easier beveling will come from getting the piece to forging temperature and then hitting the metal where you want it to move and not hitting it where you don’t.