Utsuri on Oil Quenched Blade?

[Mark S.]

Was looking closely at my WW2 Unjosai Katsunaga (undocumented smith) which has the appearance of an oil quenched blade and noticed a feature I never saw before. I’m not sure if it would be considered utsuri or another feature? Is utsuri even obtainable with oil quenching? Attached pics show light and dark striping perpendicular to the hamon that is very faint and I just happened to see them in the right light today. Does anyone have any thoughts?

Thank you in advance,

Mark S.

[16k]

I don’t think it is oil quenched.

[Lance]

To me it looks like the ji  (space between shinogi and hamon) wasn't darkened fully when it was polished,  usually done with  Nugui, an oil with (I believe) iron oxides in it.   Wartime polishers, especially for Showa-to didn't spend the same amount of time with the finishing work,  and/or weren't as skilled as traditionally trained togi so you sometimes end up with stuff that  looks a little different polish wise.   

 

Regards,

Lance

[16k]

Lance, do you even think they used nugui? It’s something I’ve always wondered.

[Lance]

I can't prove it, but I think they had to of used nugui or something similar to get such a contrast between the body of the sword and the white of the hamon, without doing all the extra work that would otherwise remove the scratches from previous steps.

Regards,

Lance

[PNSSHOGUN]

Agree with Lance, product of polishing process.

[george trotter]

Lance, do you even think they used nugui? It’s something I’ve always wondered.

Jean-Pierre,

Yes, they did use nugui in WWII polishing.

 

Article 1, rule 6 of the Rikugun Jumei Tosho rules mentions that the blade must be wiped with nugui.

 

You can read the document in the "Interesting Articles" section at the bottom of the menu page. Go down to WWII RJT document article.

 

Regards,

[16k]

Thanks you George, for the answer and for pointing me toward the article!
 

EDIT: extremely interesting read George, thank you though one question about interpretation. It seems to me that this article pertains to Gendaito since they speak of tamahagane and hocho tetsu. So do we know or just suppose that these rules also applied to Showato?

[Mark S.]

Thank you guys. The polishing answer seems like the logical answer. I just never noticed it before until I really looked and it hit the light just right... but once I saw it, it stood out and I couldn’t miss it. The more we stare at our blades, the more we see...

[george trotter]

Thanks you George, for the answer and for pointing me toward the article!

 

EDIT: extremely interesting read George, thank you though one question about interpretation. It seems to me that this article pertains to Gendaito since they speak of tamahagane and hocho tetsu. So do we know or just suppose that these rules also applied to Showato?

 

Sorry for my slow response.. those RJT rules on nugui refer specifically to traditional made blades (RJT gendaito) of WWII manufacture. I gave that rule because the question  was basically: did they use nugui in WWII?

The answer to the using of nugui on showato is unanswered, but I think first that blade needs to be properly identified as gendaito or showato and then whether nugui has been used on it.

Maybe some of our showato collectors can check their blades for nugui use and show some examples to the board. If none show up we have "basic evidence" that showato did not get nugui polish.

Good project for someone (Bruce?)...ha ha (sorry).

Regards,

 

EDIT: hope this matter is not detracting from the original post about Utsuri...

[Mark S.]

 

 

EDIT: hope this matter is not detracting from the original post about Utsuri...

 

Of course it's not detracting!  It's very interesting.  Thank you for your input and help.