What is the best oil for quenching a blade?

What is the best oil for quenching a blade?

You can check the answer of the people under the question at Quora “oil for knife blades

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  2. In the early day of the industrial revolution, whale oil was used, not a good idea these days. Almost any oil will do the job. The idea of using oil is to give a slower cooling rate than water in order to avoid cracking due to uneven stresses in hard materials. Several posters describe using used engine oil. You will likely get away with this, but it is possible to run onto trouble due to the fact that used engine oil can sometimes contain water. The same problem occurs if any oil is used too long for quenching. This doesn’t mean fresh oil for every quench, but it is not a good idea to use it for too many quenches.
    Temperature control of the oil bath can be used to further modify the cooling rate. If cold oil cracks the blade, then a warmed bath is called for. In industrial use, even the likes of molten salt baths are used, for really gentle quenches, or for holding a chosen temperature too allow transformation to a desired microstructure, but most people are unlikely to have the metallurgical knowledge to make use of such techniques. I have used this technique to study such transformations, but using molten salt baths is quite hazardous and is not recommended for hobbyists, or even professional smiths. There is no such thing as a minor burn from a molten salt bath.

    Chicago Cutlery Belden 15 Piece Premium Kitchen Knife

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  3. Motor Oils

    What is the best oil for quenching a blade?

    Image: Knifegeeky
    Motor oil is a common oil used in the hobby knife making industry. Both used and new motor oil is used in this process. It has some advantages and disadvantages.
    One advantage is new motor oil is cheaper than commercial quenchants. Used oil is obviously free. Also new and used motor oils are available everywhere. Chances are you have some in your shop or garage right now.
    Disadvantages include motor oils contain additives and potential toxins. Another disadvantage to motor oil is that it stinks during the quenching process. This can be a problem if you are doing this in an enclosed area or in your basement. I suggest not inhaling this either.
    These smells can also persist during the tempering process. That’s not a good thing if you are using your wife’s oven for this!
    Used motor oil can also leave a black film on your project that is very hard. It can be a pain to remove this later.
    Mineral Oil & ATF
    Some other common oils include mineral oil and automatic transmission fluid (ATF). These can be alternatives to using motor oil. In the case of mineral oil, it doesn’t have the additives that can be found in motor oil.
    Both can be found fairly easily but if you can’t find mineral oil, baby oil will work. It’s basically the same thing but with a tiny bit of perfume added. It will work fine.
    Commercial Quenching Oils
    There are several commercially available quenching oils on the market. These oils are specifically design for this and have special properties that make them faster or slower quench ants.
    Ideally this is what you want to use. However, they can be hard to find and aren’t available at your local Walmart. Also they can be very expensive especially if you have to ship them. They can run around $150 for 5 gallons of oil.
    Parks is a common brand that is used as a commercial quench oil. The chart below shows two of their more common oils.

    Wanbasion Black Stainless Steel Knife Set, Sharp Kitchen Knife

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