Tsukuri-komi, kitae, blade construction methods

[Jussi Ekholm]

Well I couldn't find a thread that discussed only of tsukuri-komi, kitae, blade construction methods (I'm not entirely sure which term is the proper one). I got the idea to make a seperate thread from this one: viewtopic.php?f=9&t=12594 , there was a lot of very intresting talk about construction methods and how they were used historically.

 

The main intrest of opening a thread on this subject is the famous Soshu kitae, it is a construction method that everyone seems to know (due to connection to Masamune), yet I have no information of it in any of my resource books? What surprised me most was the fact that even Kajihara's Glossary (it's my go to book on terms) has no mention of it. I know that Soshu kitae is used when talking about the 7 layer construction but doesn't the name only mean Soshu forging method? In the same way as Kyoden is referred as method of forging used in Kyoto?

 

On the subject of complex lamination methods from the book The Craft of the Japanese Sword: "More complicated composites might use four or more different pieces of steel for the core, the edge, the sides and the back of the blade - each of which must be attached in seperate welding operation. Sometimes these involve intricate layerings of high-, medium-, and low-carbon steels. The effects of these various combinations have never been fully analyzed. Presumably there are indeed differences in the amount of toughness, brittleness, hardness, and so on, but it is unlikely that the smiths who first forged these blades could have been fully aware of them. The great variety of forging methods is no doubt a reflection of the way schools developed in isolation from each other over the centuries. In some cases, complex welding schemes were misguided attempts of smiths in the late Edo period to re-create the "lost secrets" of Koto masters."

 

From The Connoisseur's Book of Japanese Swords "There is no question that steel manufacturing processes were much better developed in shinto times than previously, and that Shinto smiths were able to obtain steel of far better quality. During the late Muromachi period, older methods of sword production were abandoned amid the increasing reliance on mass production of low-quality swords. At the same time,new methods of sword production were invented, such as kobuse and makuri, which have been handed down to the present day."

 

Based on these two above quotes one might easily think that Koto blades were made by complex methods until the late Muromachi.

 

However Chris Bowen made excellent post about maru-gitae: viewtopic.php?f=9&t=12594&p=108453#p108453

 

I hope that this opening might stir some good conversation on the subject.

[Jussi Ekholm]

Not sure if this intrests anyone, but I thought I'd post this here.

 

There was a collaboration of Couple universties in Finland, Finnish knifemakers guild and Universities of Kyoto & Tokyo Arts labeled as International seminar on Art and Technology of Pre-modern Ironmaking and Blacksmithing in Japan and Finland. Unfortunately I was not able to attend this event, as it would most likely have been awesome. Hearing the lectures and seeing the tatara.

 

However I was able to find lecture dias from the Universitys website. And I'll share one of them here as it will be great for discussing the various construction methods. Feels funny as I think myself being quite far from being an engineer, yet I do have great intrest in stuff like this.

 

 

Here are my translations of them, please make corrections if I made mistakes.

 

Upper row

1. Hachimai awase

2. Sanmai awase

3. Wariha Tetsu

4. Muku

 

Middle row

5. Hizen Tadayoshi

6. Bizen Sukenaga

7. Nobukuni

8. Shihozume awase

9. Kyumai awase

10. Gomai awase

11. Makuri

 

Lower row

12. Kongobyoe Moritaka

13. Bizen Kagemitsu

14. Bizen Harumitsu

15. Seki Kanemitsu

16. Hon sanmai

17. Shichimai awase

18. Kobuse

 

Unfortunately I missed the lecture, would have been great to hear more about this dia. I've seen the construction for Nobukuni earlier and it puzzled me a bit, but Kongobyoe construction was something new for me, and very intresting, as I have developed a small liking for that school. Also Kagemitsu and Harumitsu cross-sections are intresting.

[Jacques D.]

Hi,

 

is the famous Soshu kitae,

 

 

Soshu kitae (as it is usually described) never existed.

[runagmc]

Hi Jussi, Any idea who made the chart. I would have to know who made it, and how they came to these conclusions before I would take the chart at face value. Like the "Soshu-gitae", as far as I have heard no one knows were the idea originated, and I haven't seen anything to verify it, so...

[cabowen]

 

 

Soshu kitae (as it is usually described) never existed.

 

Seems a rather absolute statement with little chance of having the data to back it up.

[b.hennick]

I recently bought a tang on Ebay. I had the end polished to see the construction. It was not all that expensive to do. Ted Tenold a few years ago displayed about a dozen sectioned blades. He wrote an article on the blades. He is a member here. I hope that he responds. Like me he is now in Japan and so may have limited time and access.

[JDinMT]

The photographs on Ted Tenold's site are at

http://legacyswords.com/nihontoCS/crosssections.htm

Very interesting I think seeing actual examples in comparison to drawn diagrams.

 

 

John D.

[Jussi Ekholm]

Very nice to get some discussion about this.

 

Here you can see the crossections as whole on Ted's site: http://www.legacyswords.com/fs_misc10.htm I sent him an email some months ago asking if he'd still have a lecture handouts leftover from the event.

 

There is a 4 page article about these cross sections on Bushido magazine Vol 2 No 3. (The main reason why I bought the magazines ). I believe Jacques D. has provided few pics of the article some time ago, and that peaked my intrest on it. Ted's cross section number 17-18 is to my understaning Bizen Kiyomitsu which has complex variation of makuri lamination, it's discussed in Bushido magazine article along with other examples.

 

Unfortunately I do not have information about the origins of the chart I posted earlier. I have seen it on couple Japanese blogs if I remember correctly. If I understood correctly professor Eiji Yamasue from Kyoto University was speaking about the properties and uses for tatara steel, so I believe he was the one who had chosen this chart for his lecture.

 

But many of the more basic types are found on many books on Japanese swords. For Mino blades in particular Malcolm E Cox - Mino-to discusses the construction of Mino swords briefly. There is a lot of information about various methods in The Sword and The Same, including one method which ends with the phrase "This method was favored by Masamune and his followers of the Soshu school". Also continued "Needless to say such process was extremely slow and costly. Moreover it was necessary to exercise the greatest care in keeping the surfaces free from grease, dirt, slag or other foreign materials which might prevent the integral welding of the layers and produce flaws in the finished blade."

 

But if I understand the book correctly, Masamune and Soshu followers made mukugitae blades from steel only without added iron. But the steel plates they welded together had different carbon percentages. Piece folded in 2 is first done up to fifteen times, then 4 similarly folded pieces are welded together and the whole piece is further folded up to 5 times. So in book it's calculated that there would be 4,194,304 layers.

 

I do not have read descriptions about construction used by Masamune anywhere else. I don't know if the method described in the book is totally made up or real, but there is a star * with description the above has been adapted from Masahide's book.

 

On the Origins of Nihonto by Carlo Tacchini has excellent part about construction. Also Ohmura's site has so much information: http://ohmura-study.net/243.html

 

Also just found this intresting picture when searching with Google.

[Brian]

A big job..I know. But is there anyone who would be willing to tackle the translations of the images above? I think there is some excellent info contained in these studies.

 

Brian