What temp and quench fluid question.

I'm slowly finishing a knife made from a farrier's rasp. I annealed , peened, and milled part of it. Once I'm done grinding, and get my pin holes drilled, I've got a heat and quench question.

Here's what I have. A 2 burner propane forge, big quench tub that could hold water, or brine, and a tub full of used engine oil, and a little oven than will get only to 500°F.

Should I heat to a certain color and quench in which one of the fluid? Or would yall rather I bought something to tell me exaclty my steel temp? Would yall rather I purchased a certain quench oil?

I'm still an amateur knife maker, so I thought I'd ask you experts.I just make knives for myself, and gifts. No way could I compete with the masterfull work many of yall do.

I take the rasp knives to 1500° and quench in Chevron 70 quench oil heated to 125° or so. That normally results in a HRC of 62 to 63. Then temper at 400° for an hour two times allowing the blade to cool in still air to ambient temp between tempers. Others do it differently I'm sure but that is what works for me.

Much appreciated Mike!

Would an infrared heat indicator work?

I've never tried one so I really don't know how accurate it would read the blade while in the forge. You can heat the blade slowly in the forge and check it frequently with a magnet. Once the blade reaches critical temp it will no longer be magnetic. Once it reaches that point heat it just a little more then quench it. A lot of makers quench the rasp or file blades in canola or peanut oil with satisfactory results.

I don't think the IR temp guns will be accurate or may not go that high.

Thank you both!

I've got magnets, I can give that a try.

What do yall use to measure steel temp?

With the optional RampMaster III controller.

Propane burner and firebrick forge for me. Use magnets to check temp and canola oil to quench. Oven to temper

^^Much appreciated, sir.