Hello Joe, you can use canola or peanut oil. It should heat treat like 5160. Heat the oil to 120 degrees before quench. 6150 should make a real tough sword.

Brion

Hey Joe, we used this steel to make the test knives during the "ABS introduction to bladesmithing" in Belgium. We did an edge quench in semi-fast oil, double temper cycle and draw back the spine 3 times. It passed the test without any problems.

But here comes a question to you, or anybody else: How do you achieve the flexibility on a double-edge knife or sword? There is no spine to treat with a torch. Does it need an extra temper in the oven or is there another trick?

Thanks

Chrs

Due to the fact that quench oils are carefully formulated and made specifically to do the job at hand for a given steel I would have to say that no, there is no equivalent, just as there is no equivalent to a wrench if we haven’t got one, only other things that we can substitute for the actual tool we need to get the job done for the time being.

Fortunately 6150 is an alloy steel that has very low demands in quench speed, so in this case a pair of vise-grips or channel locks will get you by instead of the wrench. Just about any oil will work. The thing to remember about this steel is that it is a hypoeutectoid alloy, so it will start hardening in the quench at a very high temperature and be finished hardening in the quench long before other steels, this will make it virtually impossible to do things like marquenching. So just get it hot, hotter than most other steels, and get it in the oil and agitate with the goal of room temperature as soon as possible to avoid any auto-tempering, on any level. Since this steel will form all lath martensite, it will be inherently tough with little tempering. And since that martensite will be finished forming above most knife tempering temperatures in the quench, it is important to have totally uninterrupted cooling to at least 300F.

I will not belabor the issue, but if you have considered a quality grinder or, like many, feel Chinese knockoff tools could affect the quality of your work, please reconsider the expense of a quality tool to do something as critical as hardening your blade. Heat Bath is but one, there are many more available quenchants on the market, and most as carefully designed to harden steel as a Bridgeport mill is to shape it.

This is one of the things that fascinate me about European swords. Being commonly double edged they had to perform differently in use and go up against a much wider variety of targets than the katana. No clay coating here, the Europeans simply had to be on their "A" game in hardening and tempering their blades to just the right degree to do the job.

Awesome, thanks everybody for the input! You guys rock. I understand 100% that a household oil isn't an exact equivalent to professional oil and if I was heat treating in my shop, under everyday circumstances, I would definitely be using it. Unfortunately, in my current situation I need to sacrifice perfection for availability. Essentially I'm going to be flying somewhere exotic to heat treat this sword and I don't want the hassle of transporting 'good' quenching oil if I can simply buy a cooking oil when I arrive. It's a really long story, but I'll post some updates when I'm done in a couple weeks.

Thanks again!