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Old 03-18-2018, 06:11 PM
epicfail48 epicfail48 is offline
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Join Date: Aug 2017
Location: Springfield Mo
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Quote:
Originally Posted by Gblack View Post
I never even thought about that. As far as heat treatment goes, what exactly is entailed? I’ve seen and read that it is just quenching and some that say a true heat treat involves a few cycles of tempering in an over or kiln. Makes it kind of confusing. I already intend on about 2 normalizing cycles before oil quenching, followed by about 2-3 temper cycles. Is that wrong or too much?
Hoo boy, that ones a can of worms to open up...

At its core, heat treating a knife is just getting it really, really hot, then getting it really cool really fast, then getting it a little hot again. Devils in the details though. Every type of steel heat treats a little differently, the "really really hot" temperature ranges from 1450f up to 2100f, the duration of "cooling it really fast" can be anywhere from .5 seconds to 2 minutes, and "little hot" can be anywhere from 400f to 1000f. Theres a lot of variables in there, to the point where you can devote an entire website to it.

I recommend starting off with 1084 steel because of how easy it is to heat treat. Its a plain carbon steel, meaning that the majority of it is carbon and iron, with a touch of manganese(?) thrown in to make the heat treatment easier. To heat treat it, all that needs to be done is to bring it up to 1500f, little past red heat and when the steel loses its magnetic properties, then quench it in oil, plain canola oil works fantastic. From there, the steel is glass-hard and extremely brittle and it needs to be tempered, or softened just a touch. Also easy to do, just toss it in an oven at 450f for an hour.

I say that 1084 is easy because the temperature for the initial heat doesnt need to be exact, a simple charcoal fire with a hairdryer as an air blower will get the job done just fine. Quenching is also easy, nearly any oil will work. I use canola because its cheap and easy to fine, but peanut and mineral oil will also work, and some people will use things like motor oil. As a comparison to 1084, something like 1095 steel will require slightly better heat control, and a much better quench. The higher carbon content of 1095 means it requires a faster quench than the more common oils can provide, either water/brine (very fast, very harsh, lot of broken blades) or an engineered quenchant (hard to find, bloody expensive at ~$150 for 5 gallons). Other steels get even worse, stainless steels require very exact, very high temperatures in an oxygen-free environment for specific lengths of time.

Like i said, its a pretty complicated topic. Honestly, making the blade is the easy part. Best i can tell you is start out with a simple steel and learn on the way. If youve got any other questions and are free on sundays, hop in the chat room, its a great place to ask
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