TA’s wonderful videos include this one, and to date I’ve probably made at least a dozen of them, large and small. At the start he partially cuts an end section that then gets drawn out to become the handle (his hammer work is really fine). I’ve made these from 1075, 5160, 1084, 80Crv2, 1080, and 8760, and he uses O1, which I’ve not tried. Even when working carefully and keeping the steel very hot it is not uncommon to develop small stress fractures, and sometimes catastrophic ones, at the initial bend point where the handle gets drawn out.
What I’m curious about is what you all think might be the best carbon steel for this particular forging move? The technique really is useful for creating handles and tangs for all sorts of choppers and also woodworking tools. But the bend seems to be very high stress and drawing out the handle sends a lot of vibrations back to this stressed area (from the start you can see definite stretch marks in the steel). Are chromium or magnesium desirable addition to the alloy or more prone to fracturing? Could it be that the bend needs to be done at near forge welding heat? I’ve not really thought about to date but I also am curious as to what steel you would think is best suited for this type of single steel project.