Thread: Looking for the best heat treatment for O1

Thank you for your help with my question. I understand what you are doing now...

First, the bars of O-1 are likely just fine from the steel mill, but that you have added the insurance of the normalizing routine will take care of any unusual heat history that might have happened to the bar when you did not have it under your control. Steel mills should not do much out of the ordinary but I have had "factory" bars that did not behave as they should. It helps to always be observant about such things.

Second, that you are grinding and not forging means you have probably avoided any large grain/particle problems already. Grain growth in O-1 requires temperatures that exceed 815C/1500F far longer than 15 minutes. I think your process is a good one. Very likely you could save yourself shop time by not having to normalize your blades (it's more for people who forge their own blades at uncontrolled temperatures). If you noticed any warping during the normalizing process, that is the place to correct it. And remember it (journal - notebook) about that batch of steel from that supplier for the next time.

Third, I don't think your oil temperature is too hot. I hardly ever heat my quench oil for O-1 (shop room temperature maybe 50F) and it will produce good hardness. I am not getting any feedback that the edges are crumbly. You can experiment by doing quenches at lower temperatures. But I am spoiled by better equipment and with good thermal controls I can predict hardness to a very fine degree just with time and temperature.

As has been said, O-1 is almost the perfect beginner's steel, very forgiving, and a highly under rated good performing blade steel for razors and knives.

Lastly, we're back to either edge geometry (spine width to blade width) or bevel setting/honing techniques and there are good comments here already about that.