gnique
Member
There is something that I do that I have been told that I should NOT do. I make blades by the batch. I first do all of the shaping that I am going to do while the blade steel is as it came from my supplier. The next thing I do is apply an anti oxidant compound to all of the blades. The next thing that I do is harden all of the blades. I have read that a blade should be tempered very soon after hardening. I don't do that. It takes just as long for the oven to cool down as it does to heat up so I let the internal temperature drop to about 1000 or 1100, pop in a blade and run the instruction set that I have programmed into the controller. I pile up the hardened blades until I have hardened them all. I then temper them all once (as many as I can get in my oven) and then straighten and further temper them one at a time. The straightening part is important to me because I use thin (3/32" and 1/16") steel for kitchen knives.The only method that I have to check for hardness is with a set of hardness files that I got from Grizzly Tools. Here is my question and a finding that I think I have perceived: Am I doing any real harm in waiting up to a week or two weeks to temper hardened blades? Also I seem to have found with my files that the blades are one hardness just after quench and usually a higher hardness at sometime an hour or day later. Is this right? I have never been given any dependable instruction on how to correctly use hardness testing files - I just kinda do what seems right to me. But I swear that my blades sure SEEM to get harder after some time has passed after hardening. I am a numbers person so I really don't even LIKE the word "seems" but, as I said, all I have are those files. One more thing, 15N20 steel is the steel that seems (that word again) have the most noticeable change in hardness. The hardness never seems to go down; only up. I don't even know if this is even worth wasting time on but both these items have piqued my butterfly like curiosity. Nicholas Jasper