Oil Quenchant for Heat Treating

[TarAlderion]

Greetings all.
I have a qestion in reguards to obtaining oil for heat treating blades. As I have increased my blade production and blade size I realize that I need to get a large quantity of oil for quenching durring the heat treatment. Previously to this I was using a small amount of oil (say about a gallon) for quenching, as I was only doing smaller knives, one at a time. But with larger blades and more blades being treated at a time, I need some larger amounts of the stuff to prevent it from reaching flash point and causing a fire, and to ensure a full quench for the entire blade. So, my question is, firstly what sort of oil do you use for quenching, where do you get it, and the price (roughly, I know it will vary per region)? I know where to get smaller amounts of vegetable oil, peanut oil, and automotive oils, and the like, but by the time I purchase the quantity I need (probably 5-10 gallons or more possibly) I will have spent a large amount of money, which is something I lack at the moment. So I suppose I am looking for the cheapiest way to go to get the job done.

Any help is greatly appreciated.

Tar Alderion

[Nolano]

Well, mostly I use old car oil, stuff thats been changed out already, and I usually get it for free. However, I would prefere vegetable oil for blades, as it doesnt leave the blackened finish you get with auto oil. I despise the smell of oil quenches, though, using automotive oil makes it smell like your cars transmission went out, and using vegetable oil makes it smell like your local mcdonalds burned down.

[cheftjcook]

Tar Alderion, Any and All food establishments are glad to give you there old fryer oil. We were throwing away, "properly disposing of(grin)", about 40 to 50 gallons a week between a few places. Kitckens, depending on locals laws, usualy have to pay some one to take it away and recycle. So for some one to come and take it for free, I'm happy. We now have a guy with a desiel type converion for his truck that uses strained fryer oil as the fuel. He stops by regularly and we are happy to help him, we save it for him in containers he gives us. I don't fully understand how the conversion works but he runs for free and we don't have disposal issues.
As I was taught, the oil viscosity does not change only the dirty particles in the oil and there effect. So if you strain it well, it should work well for you. Flash point on fryer is very high as well and is ment for heavy use. And depending on what was cooked in it you also have a neat smell of fries, fish & Chips.(grin)
Hope this helps
TIM

[oakwoodforge]

I was in "wally world' just the other day and happened to notice they are clearing out the summer time BBQ items. They had a 5 gallon turkey fryer Pot & lid with a thermometer, 4 gallons of peanut oil, a propane burner with regulator & hose as well as a anti-tip stand all for under $50.00 Come to think of it I should go buy one if they still have any left. That would be just the perfect thing for bigger blades.

Hope this helps

Jens

[Tyler Murch]

Burnt motor oil is a very slow quench. Too slow for most oil hardening steels.

[HWooldridge]

Motor oil often can have gasoline mixed in, which can be scary at best and deadly at worst. ATF (automatic transmission fluid) works reasonably well as does most any vegetable oil. The used fryer oil route is a good one and environmentally friendly but I simply bought 10 gallons of Texaco Quench-Tex about 20 years ago and keep it in a galvanized milk can. Was about $3 a gallon then - don't know if the cost is higher now. With the milk can, moisture is kept out and the lid can be flipped back on in case of a fire. I'm quite sure this supply will last me the rest of my smithing career since very little is consumed or spilled during use.

[Dodge]

I haven't done that much oil quenching, but I concer with cheftjcook on the veggie oil source. Fast food restaraunts will probably give it away. At least thats what the articles have been saying as a source for bio-diesel base.

[nc_cooter]

I use canola oil from wally world to quench my 1095 blades. It has a high flash point and is cheap. Preheat to about 130F and it works great.

[TarAlderion]

Cost and avaliability was the main issue I faced. I think I might go hit up one of the fast food places about here and see what I can do. That sounds like the best route. I thought of checking with an automotive repair/oil change place to see about that, but I really didnt want to mess with automotive oil, as the various reasons stated by Tyler and Nolonao. Should have though of the fast food places myself, but didnt think of it. Anyway, thanks for the ideas I should be able to make something work now.

Tar Alderion

[Nolano]

Tyler, Ive never found automotive oil to be a "too slow quench", I've made plenty of tools with it. At my local Costco(Huge warehouse store that sells in bulk) I remember you could be an extremely large bottle of soybean oil(I'd guess 2-4 gallons, it only measured it in pounds, strangely) for $13.