quenching oil | Heat Treating | Forum

ide start with the vegtable oil smells better than tranny fluid...

Good Morning,

When I was looking for quenching oil, it was available in 45 gal drums or by the rail car load. I wanted to purchase a few gallons from a user in Vancouver, when I was almost on my way over, I found out he determined that it was hazardous material and wouldn't sell me any. I had to purchase 2 drums of different grades of quenching oil. I used quenching oil for a few years and then figured out that for what I was working with I got a better hardness with water. Magic, simple water. I can't remember which oil company I purchased them from, but I have the Material data sheets in my file. I know quenching oil, ISN'T HAZARDOUS GOODS. It is very benign actually. Using proper quenching oil is more consistent than using automotive oils, with a higher flash point.

I still have part barrels of Quenching Oils. No I won't mail it. If anyone is serious about using some I can bring some with me to a NWBA Conference.

Ciao fur now,
Neil

Thought I'd add my 2 bits to this one.  Quenching carbon steels for hardening is a pretty complex issue in it's most technical aspects.  This can be too much info. for a beginning smith to assimilate when he/she just wants to make a couple of knives, or harden a punch.  For some basic info. that doesn't get too awfully technical, but gives enough info. to get started with some confidence of a good outcome, I recommend Wayne Goddard's The $50.00 Knife Shop revised" , and/or his "The Wonder Of Knifemaking 2nd Edition".  They can be purchased on-line, or directly from Wayne.  Both have great sections on heat treatment from a home shop perspective that doesn't require an expensive heat treatment kiln and controller.  It can be done with your forge or torch, and tempering with your forge, torch, or home oven.  They cover when and why of different Quenchants.  I'm fond of Wayne's Goop Quench for many carbon steels, but not all of them.  It is handy for basic shop use as it hardens up to boot grease consistency when not in use, so it minimizes spillage, and can be hauled about for demos. without big spill problems.  It isn't fast enough for some carbon steels, so I use a combination of warm water for 1-3 seconds, then into a fast quench oil for those.  For any steel below 1040, or below .40 points carbon, I use Super Quench, which is a screaming fast quenchant developed at Lawrence Livermore Laboratories.  The formula to make it is available on-line.  It stratifies during storage, so stir it up before use.  It is a very severe quench so follow the rules re: below .40 points carbon use or be prepared for several pieces to come out of the quench.  It is my go to quench for HC marked railroad spike knives, or if you want to make mild steel into a spring.  It will get maximum hardness out of low carbon steels.  Anything above low carbon steel it will destroy as it is WAY too fast.  You've been warned.  It is just water, detergents, and salt, so it isn't a hazardous material.  Always have a metal lid for your oil or grease quenchants available to smother a fire started by your hot tools/blades/tongs etc.  This can be minimized by using cold tongs to remove blade from forge so you don't have hot metal heating the surface of your quenchant and causing the oil to flame.  Sometimes this cannot be avoided, so expect this when quenching the end of a big tool, or edge quenching a blade.  Keep flammable mtls. away from your quench area, and clutter away from your quench tank so you can smother the fire quickly and easily with the lid without panic, or knocking things and possibly the flaming oil over.  Ensure plenty of ventilation for you so you don't breath a lot of quench smoke.  Use a larger quench tank if possible so that your tools/blades do not over heat your whole tank past the flash point of your oil/oils/grease which is usually around 400-500 degrees F.  For my goop quench I use a hot plate to warm it to 130-150 F. before use, then shut off the hot plate.  It is liquid at this point and now is an oil.  This allows me to adjust my quench plate to the depth I want for regulating the depth of edge quenched blades.  My quench plate is a 1/4" aluminum plate that is tapped at the corners for short all thread legs to adjust the plate to different depths to edge quench a blade to a given depth, and leave the back soft.  The plate is drilled with large and small holes until it is more holes than plate.  This allows  convection currents to move hot quenchant up and away from the blade, and cooler oil from below to flow up and speed the quenching process.  I also use this in other quenching oils, but with the semisolid goop, you have to liquefy it to see, and adjust the plate.  Small tools or blades can be quenched into solid goop, or into a groove melted by a piece of hot scrap steel if you don't need to use the quench table/plate.  A word of caution here:  Don't make the mistake of leaving the legs of your quench plate/table sticking out above the top of your quench tank, as this will prevent you from being able to use the tank lid to smother a flaming quench tank fire.  Just sayin....Murphy's always lokking for a chance to pop up his ugly head in your shop, so always be thinking ahead for the what could happens when using flames and tools.  Be safe out there.