# Which Quenching Oil is Best for Knives?



## Larrin (Jul 19, 2021)

I did a big study on different quenching oils (six of them) in addition to water for 9 different steels to see in what conditions the different steels will fully harden. If you have been worried you are using the wrong oil this study is for you. In addition to this fun study, I have made my first YouTube video to present my findings. However, for those that prefer reading or want the version with more discussion and details I still have a written article.

Which Quenching Oil is Best for Knives? - Knife Steel Nerds


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## MarcelNL (Jul 19, 2021)

interesting stuff, not being anywhere near a steel nerd....is there a link between specific capacity for the various oils/water and steel hardness ?


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## Larrin (Jul 19, 2021)

MarcelNL said:


> interesting stuff, not being anywhere near a steel nerd....is there a link between specific capacity for the various oils/water and steel hardness ?


When I google specific capacity all I'm finding is a term referring to well pumps. Do you mean heat capacity?


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## MarcelNL (Jul 19, 2021)

sure...the word heat got mangled somehow between my typing and pressing enter...sorry

specific heat capacity!


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## Larrin (Jul 19, 2021)

MarcelNL said:


> sure...the word heat got mangled somehow between my typing and pressing enter...sorry
> 
> specific heat capacity!


The papers I looked at on canola oil and other oils did reference specific heat capacity measurements so that does seem to be an important measurement.


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## MarcelNL (Jul 19, 2021)

thanks! I'm guessing that both viscosity and specific heat capacity are important, is agitation used/a factor too?

forget it, just watched some of the footage! interesting stuff!


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## pennman (Jul 20, 2021)

Where did you get the W2 you used for this? Also, your quench technique on video shows you highly agitating the steel immediately upon quenching. What does that agitation do to the formation/disruption of the vapor jacket? If the vapor jacket is disrupted, what does that do to the hardness curves?


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## gregfisk (Jul 20, 2021)

This was very interesting Larrin. I’m a fairly new knife maker and only a hobbyist. I have only used the canola oil that you used in your testing so far. The one difference being that I’m using 1/16” 1095 and 15n20. It appears that if I’m going to use thicker steel in the future I’m going to need to invest in some commercial oil. Both of the steels seem to harden for me, so I’m guessing that’s because of the thinness of the steel. Thanks for posting this information, I learned a lot.


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## Larrin (Jul 20, 2021)

pennman said:


> Where did you get the W2 you used for this? Also, your quench technique on video shows you highly agitating the steel immediately upon quenching. What does that agitation do to the formation/disruption of the vapor jacket? If the vapor jacket is disrupted, what does that do to the hardness curves?


The W2 came from NJSB. The suppliers/manufacturers are listed in the written article. Agitation helps break up the vapor jacket and would therefore be expected to potentially increase hardness.


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## VICTOR J CREAZZI (Jul 20, 2021)

gregfisk said:


> This was very interesting Larrin. I’m a fairly new knife maker and only a hobbyist. I have only used the canola oil that you used in your testing so far. The one difference being that I’m using 1/16” 1095 and 15n20. It appears that if I’m going to use thicker steel in the future I’m going to need to invest in some commercial oil. Both of the steels seem to harden for me, so I’m guessing that’s because of the thinness of the steel. Thanks for posting this information, I learned a lot.


I also have had good results with heated Canola oil and thin sections of 1095.


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## rocketman (Jul 21, 2021)

It appears to me that there is a lot of opinion about hardening steel, without any direct evidence. In my shop, I have a rockwell tester,a controlled heat oven, and before I would venture an opinion as to the results of hardening in various media, I would do a rockwell test on the resultant steel.. Of course there are other factors, such as temperature of the quenchant, but I also control for that... Even with all of that science, there is still variability, not a lot but still some. Otherwise, we are all just doing a subjective guess.


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## gregfisk (Jul 21, 2021)

rocketman said:


> It appears to me that there is a lot of opinion about hardening steel, without any direct evidence. In my shop, I have a rockwell tester,a controlled heat oven, and before I would venture an opinion as to the results of hardening in various media, I would do a rockwell test on the resultant steel.. Of course there are other factors, such as temperature of the quenchant, but I also control for that... Even with all of that science, there is still variability, not a lot but still some. Otherwise, we are all just doing a subjective guess.



Of course you are correct. However, you can get an idea of whether the steel got hard. There are several tell tale signs that tell you if the steel is hardened. Grinding on it with your belt grinder, sharpening it with a stone or watching it shatter when you drop it on the floor does let you know something about how hard the steel got. You don’t know how hard the steel is from a measurement standpoint but you do know if it got hard all the way through.


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## TB_London (Jul 21, 2021)

Interesting and wish I could get parks 50 over here.

Guessing the best way to test oil speed at home is just to quench some samples and see which works? Is there a more scientific way available without needing large investment?


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## Larrin (Jul 21, 2021)

TB_London said:


> Interesting and wish I could get parks 50 over here.
> 
> Guessing the best way to test oil speed at home is just to quench some samples and see which works? Is there a more scientific way available without needing large investment?







__





Heat Treatment | GFS Knife Supplies


Quenching oil for the heat treatment of steels such as 1095 or Silver Steel



www.gfsknifesupplies.com


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## TB_London (Jul 21, 2021)

Larrin said:


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Cheers- claimed to be a substitute but someone I know that brings in a personal supply of parks tried that side by side and it wasn’t as fast as hoped sadly. 

I’m currently trying this - hoping will work with some 3mm 26c3 and sc125



https://www.exol-lubricants.com/assets/data-docs/tds-new/Excelquench-L603Z-Q016.pdf




I see kinematic velocity referred to often with quench oils - do you know how they should be interpreted?

Cheers! Tom


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