Oil Quenched Swords Question

[Jim Rogers]

I got some translation assistance from the crew here with great appreciation on my part. One comment from Brian, who I respect for his knowledge, regarded his gut instinct that the sword in question might have been oil quenched rather than water (traditionally) quenched. How can one tell? The swordmaker is noted on the sword guide as 'undocumented' as a WWII era swordmaker. That sounds like he was relatively unknown. So what to I look for to determine oil quenched or water quenched.

 

Again, I respect Brian's best guess but it would be nice to know. The makers name was Minamoto Yoshiharu.

 

Thanks, Jim

[Jim Rogers]

Oh, and what would that do to the value? Thanks.

[nagamaki - Franco]

Hello,

 

It becomes quite easy to tell once you learn how nioi and nie due to water quenching looks, bright, reflective, white, well defined. When from oil these characteristics will not be present, the hamon will look shadowy, not well defined, not reflecting the light back in a bright manner, and in some cases you'll even see different colors reflected back when you play with the light/angles. 

One of the best pieces of advice as a beginning collector looking back was being told to purchase Yamanaka's Newsletters revised sold by the NCJSC. In them you will find all these types of questions answered and much more.

 

Value? Not highly sought after.

[SwordGuyJoe]

In addition, most hada for showato blades are muji

[Prewar70]

So it's a traditionally forged blade but oil was used vs. water during quenching?  There must be more to it than that and why use a scarce resource like oil during wartime when water is free?  I haven't googled it, thought I'd ask quick.

[kissakai]

Hi

I understood oil quench was more forgiving than water which is so much more abrupt during the quenching process but I'm not a sword guy

 

 

Grev UK

[Stephen]

Grev has your answer

[nagamaki - Franco]

So it's a traditionally forged blade but oil was used vs. water during quenching?  There must be more to it than that and why use a scarce resource like oil during wartime when water is free?  I haven't googled it, thought I'd ask quick.

 

 

Not traditionally forged/made. Oil is slow cooling avoids hagire. 

[SwordGuyJoe]

Non-traditional can refer to the steel used (western mill steel vs. tamahagane), forging techniques (man made vs. machine made and man finished), and/or the quenching method (water vs. oil). Put a check in any of these boxes and you have a non-traditional blade.

[ROKUJURO]

Gentlemen,

there is a whole world between steels that can be water quenched and those that have to be oil quenched.

Hand-forged blades from traditional TAMAHAGANE steel require a rapid cooling process (water) while the same procedure will cause a blade made of modern industrial steel to crack. This has to do with different content of alloy metals in the latter such as manganese, chromium, nickel, silica, molybdenum, vanadium, and many others. TAMAHAGANE on the other hand is an almost pure alloy of iron and carbon. 
 
Without going deeper into metallurgy, we can say that different steels require different heat treatments and show different results.

[Jim Rogers]

Thanks everyone for your input.

[Dave R]

Bear in mind that the Militaria Guys are for the most part perfectly happy with oil quenched blades, It's the Nihonto collectors for whom it is an anathema. 

[Jean]

Take for example a hammer. In the past, it was water quenched thus it could brittle and send splinters in the eyes of the handler. Nowadays, for example, Stanley manufactures oil quenched hammers which don't brittle anymore thus avoiding any injury and above all consumers mass action lol: