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I just finished 2 plasma cut blades. How should I go about heat treating the blades after sharpening? I only have an oxy/acetylene torch to heat the blades so how should I go about it. The blades are made of mild steel about 0.77 in wide and about four in long. I would upload a photo but I forgot my USB cord.

Hi all, I've got some questions about normalizing before a quench. In "The Complete Bladesmith", Jim Hrisoulas cautions against leaving steel for too long above critical temperature when quenching, and against quenching multiple times, because the metal is subject to rapid grain growth above that point. I've seen other sources talk about normalizing the steel before the final quench (often repeatedly) to relieve stress and refine the grain. As I understand it, normalizing (a basic 10XX carbon steel) involves heating the steel above the critical point and then letting it air cool. How does one grow the grain and the other shrink the grain? Does normalizing need to happen at a lower temperature? Or is the grain size determined by the rate of cooling?

Properly heat treated this steel is great! It cuts very well. It has good contrast and is easy to etch. I know many knife makers who prefer to work with this steel! This is how we heat treat our stainless steel Damascus when the layers are AEB-L and 301. HEAT TREATING: Preheat furnace to Austenizing temperature Place blade in furnace​ Allow furnace to cycle back to Austenizing temperature Soak for 15 minutes Quench in oil Temper 2 times for 1 hour each time Quench in liquid nitrogen for 4 hours and re-temper 1 time HEAT TREATING TEMPERATURE MATERIAL AUSTENIZING TEMPER Stainless 1925F 350F

Currently in history, I'm studying the Homeric period, and especially the Epics, the Iliad and the Odyssey. I got a reading assignment, chapter 9 of the Odyssey, the situation with the Cyclopes. I will say it's pretty gruesome at places, but at the area where they're blinding the Cyclopes, I found some interesting text. I'm not quite sure how exact the text is, as it gives Roman names instead of Greek, but this is supposed to be a very close translation. The thing is, was heat treating as such developed by the time of Homer (7th and 8th centuries B.C.)? I do know that Iron would have been well developed by that time, but I had thought that heat treating came much later; during the time of the Roman Republic at least. Any thoughts on this? EDIT: Also, he says the quenching 'tempers' the iron. I'm pretty sure that the old 'tempering' is the word for the whole heat treating sequence; is that correct?

To preface i want it known that yes i am aware of parks 50 being the ideal quenchent for simple steels however im trying to get a few knives done before next week as they are for a school project so im on a time constraint as far as getting a batch of parks 50 and also my budget will not allow that at the moment. So i am moving my attention towards oils available in grocery stores i know canola oil is a favorite among many however next to a bottle of canola i noticed a bottle of this grape seed oil. i sloshed both around to see how they compare in terms of viscosity and it appears that grape seed oil is much thiner and was close to what i remember parks looking like (i had a 5 gal thing of it but it was very sadly tossed in a move still calling myself stupid for that one but oh well to late now) Looking on the back of the bottle it said that it was ok to work with up to 425 degrees which is fairly close to the working range of canola. Would grapeseed oil work better than canola as it is a thinner liquid? my thinking is that thinner fluids allow for a faster extraction of heat because the molecules are much more free to move around but that might be complete bs.