Shingane?

[Ken-Hawaii]

I'm working on a project to figure out just when kobuse began in Japanese blades, & that's turning out to be a very interesting study.

 

But what I'm also trying to find out is just how much shingane/core steel was used during the Nambokucho, Muromachi, Shinto, & Shinshinto periods, not to mention shinsakuto. Obviously, kobuse depends on a flexible core for optimal blade performance, but just how much never seems to be discussed. Anyone have some insight?

 

Ken

 

[Geraint]

Hi Ken.

 

I am sure that you have already come across this link but just in case.....http://www.ksky.ne.jp/~sumie99/shingane.html

 

It might be interesting to correlate schools whose blades are regarded as being "thin skinned" with wazamono rankings.

 

All the best

[Ken-Hawaii]

Yes, I knew about that link, Geraint, but it really doesn't have much useful detail. The Shinsoku & Masatsune blades don't really show what I think of as shingane, & I'm 90% sure that Nobutsugu's & Norifusa's tachi don't show shingane, but rather odd hada. The Kanemitsu tanto is really the first example of the loss of the skin steel that I believe is valid, but think of how late that is in sword history. The Chinese were implementing kobuse around 900 AD, & probably earlier, so why did it take Japan another few hundred years? Have you ever seen a Kamakura blade that wasn't monosteel? I haven't.

 

Ken

[cabowen]

There are several theories out there concerning marugitae and the change to multipiece constructions. Some think that the switch from monosteel to a separate core and kawagane was done to conserve precious high quality steel, others as a method to improve the performance of the blade. It may be the case that it was done to conserve high quality steel originally, but then an improvement in performance was noted which spawned experiments with varied, multipiece construction that culminates with the so-called Soshu construction which uses many separate steels.

 

I don't think you will find much written on this in English though there is quite a bit in Japanese.

[Jussi Ekholm]

I'm on my phone and in bus so I can't write a long reply. Have you read On the Origins of Nihonto by Carlo Tacchini?

 

You can find the PDF here: http://www.google.fi/url?sa=t&source=web&cd=1&ved=0CBoQFjAA&url=http%3A%2F%2Fwww.webalice.it%2Ftsubame1%2FDownloads%2F1%2529%2520On%2520the%2520origins%2520of%2520Nihonto.pdf&ei=JwXeVOrQEuTOygOIpILACw&usg=AFQjCNGodfavw9vUJnC_qaCmlddW691I-Q

[Ken-Hawaii]

Thanks for the feedback, Chris. I wish that my interest had run to Japanese when I was a kid, instead of the romance languages. I'm fluent in Spanish, & can make my way through Portuguese & Italian, but that doesn't help much when it comes to Nihonto.

 

 

Yes, Jussi, I've read it, & it's quite fascinating. In fact, I was one of Carlo's proofreaders. Carlo does state that shingane likely appeared in Nara or early Heian, & says that he disagrees with Dr. Honma Junji statement "that they, unlike later swords, do not have the Shingane (“core steel”) added inside. They were probably made by hammering the Kawagane (“skin steel”) flat and folding it lengthwise, with the edges meeting at the mune (back) for cross sections (sectioned parts) of swords unhearted from proto-historic tombs (Kofun) frequently show such construction." Carlo then goes through a number of iterations to define what he thinks of as interpretations of how early blades were constructed, although many of his reads don't agree with other experts....

 

 

What I HAD forgotten about was the laminated chokuto he shows on page 15 from late Kofun, around 700 AD, that even I have to agree is an early example of kobuse. Okay, so that puts at least a vague starting point on the start of kobuse implementation in Japan. So many thanks for reminding me, Jussi!

 

 

Okay, now on to determining just how much shingane went into blades over the years. As a starting point, although tamahagane was fairly precious during Kamakura, obviously monosteel blades used nothing but that as material. In contrast, during the Sengoku jidai, when smiths were pounding out hundreds of kazu-uchimono blades for battle, I'm sure that they used only a small fraction of tamahagane, with much larger amounts of less-precious shingane; thus, the much poorer appearance of blades from that period, with thinner kawagane that polished down to shingane.

 

 

Thanks to all for your ideas.

 

 

Ken

[cabowen]

tamahagane is the generic term for steel made in the tatara process. Shingane and kawagane are both tamahagane. The difference depends on the carbon content and the quality. When a load of steel is made in a tatara, you get a variety of steel out....

[Ken-Hawaii]

An excellent point, Chris! So, since Kamakura blades are monosteel, what did Kamakura smiths do with the 70-80% of steel that was too soft to use for kawagane?

 

Ken

[cabowen]

They used the oroshigane process in their forge to add/subtract carbon as needed. Or gave it to their buddies in Soshu to mix in with the hard steel....