Question in regards to Hada patterning

[JHrisoulas]

Hello: (I hope this is in the right section).....

 

While I am doing research for my 4th book I am delving rather deeply into how to visually re-produce the various Hada that is seen..While I am working all this out I was wondering...Are there any swords that show a twist in the Hada?

 

From my research I can pretty much duplicate the visual appearence of Hada like Mokume and Ayasugihada by surface manipulation of the laminate but as I was working I realized that I have never seen a blade that had the material twisted in its forging.

 

So my question is: Does anyone know of any blades that exhibit evidence of having the material twisted during the forging sequences??

 

Thank you for your time

 

JPH

[cabowen]

Noda Hankei is a famous smith who started his career as a gunsmith. His hada is unique and some think that he may have used some of the twist forging more commonly seen in gun barrel making.

[watsonmil]

Dear JPH,

In trying to visualize what would happen by putting a twist rather than a fold, ... I should think that this would actually weaken the metal structure, as the smith is going to have to hammer each of the cross-sections many more times than the flats in order to come back to a flat billet surface. To answer your question more simply, .... No, ... I have never seen evidence nor read where a Japanese smith has ever used such a technique.

... Ron Watson

[JHrisoulas]

Hello:

 

In reply:

 

cabowen: Thank you..this is a starting point. I will see what I can dig up in regards to this gentleman. Having made a considerable number of pattern welded gun barrels I can see where this fellow would be "coming from"...More for me to research. THANK YOU...

 

watsonmil: If the welds are solid and the material is properly worked there should be no problems at all as far as strength goes, in fact it should actully, to a point,m help to strengthen the whole assembly as the weld lines will not be parallel, rather they would be more like strands in a rope...Now if the welds were NOT as good as they should be..then other problems can arise, some which can cause a catastrophic failure...

 

What I am asking is (maybe I wasn't clear as I should be in my original post) after the last welding course, before the bar was incorporated into the construction of the sunobe, are there any pieces that show evidence of having been twisted in order to manipulate the Hada into a different pattern? The result would look something like the European/Asia Minor "Maiden's Hair" or "Waterfall" pattern, with the weld lines running down the blade like the stripes on a barber pole...

 

This is to satisfy my own curiosity more than anything else as I am about to start my "Sword of 100 Abominations" just for grins and giggles...

 

JPH

[Bazza]

Dear JPH,

 

This contribution probably comes under the heading of "useless information", but I submit it "just in case"...

 

There is a style of forging called tanzaku kitae, described in one online dictionary as "Forging together various pieces of different kinds of steel and iron to get the required qualities for sword steels." A more comprehensive description is found on David Pepin's website about a RAI NORIMICHI katana:

--------------------------------------

"RAI NORIMICHI" WAS ONE OF THE FOREMOST STUDENTS OF "RAI KINMICHI" IN KAN-EI (1624 AD). HE FURTHERED HIS STUDIES WITH THE "HORIKAWA MON" UNDER THE TUDOR SHIP OF "UMETADA MYOJU", AND WORKED IN OSAKA (SETTSU PROVINCE). HE WAS TRULY A MASTER AT "TANZAKU KITAE", THE COMPLEX COMBINING OF "HADA STEELS", I.E.: MASAME, AND ITAME (EXTREMELY DIFFICULT TO PROPERLY ACHIEVE). THIS BLADE IS A SUPERB EXAMPLE OF HIS GREAT SKILL!

--------------------------------------

http://www.samuraisword.com/nihontodisp ... /index.htm

 

Regrettably my Rai Norimichi katana is out of polish so I cannot comment on whether any "twisting" is evident in this forging technique.

 

Regards,

BaZZa.

[JHrisoulas]

Bazza:

 

Thank you and there is (at least to me) no such thing as useless information. What you are describing is what I (and many other smiths) call "composite construction", I.e. taking two or more seperate pieces and incorporating them into a blade.. Kobuse construction would be a composite blade, as would San Mai (in its variations) and the same with Wariha Tetsu. Now a "homogenous" blade ( Maru?) would not be, in my opinion a composite blade even though it is more or less a "laminate" of sorts due to the refining of the Tahamagane and the inclusion of various grades of raw materials, due to the fact by the time the forging/welding courses are completed the content within the piece is pretty much homogenous.

 

Now having made quite a bit of my own "Jim-agane" and playing about with that I can say by the time one is on about the 10th weld/forge cycle things are pretty much well on their way to being more or less homogenous and by the 12th to 15th cycle they are pretty well refined.. Now proper thermal cycling also plays a very important factor if forging a sword (especially) and that seems to be a "forgotten step" in the making of a solid blade, one that is very often not mentioned in texts and other sources...

 

 

The photo below shows two pieces of Jim-agane that I am refining for research purposes. Both pieces are on their 12th weld/forging course.. Looks like I will have enough for two decent size sunobe..or one real MONSTER of a sword if I weld them together. Spark tests show approx 80 pts of C or so..a little high but still use-able for a water quench.

 

Thank you once again for the information..

 

JPH

 

Oh..if anyone is interested..once I get this section wrapped up..I may be able to send out a "peek" at it to interested individuals once I get it all out of my head. This will be another two months or so as I am just now really getting into the guts of the thing now that I covered the differences between using laminate vs modern homogenous materials in composite construction...

[IanB]

JPH, Although this information will be of little use, I once did see (probably 20 - 25 years ago) a small tanto in which the blade showed exactly the same structure as what is known in the UK gun trade as 'Rose twist damascus'. I came to the conclusion at the time that it may have been made from a piece of gun barrel brought to Japan in the 19th century.

Ian Bottomley

[Carlo Giuseppe Tacchini]

I came to the conclusion at the time that it may have been made from a piece of gun barrel brought to Japan in the 19th century.

Ian Bottomley

 

More than possible. Sometimes you find on the Nakago inscriptions describing the use of

steel from gun barrels.

[Nihonto Chicken]

FWIW, I have a modest mumei yoroi doshi that apparently has a different metal wrapped about it in barber pole style, resulting in a striped yubashiri effect. These misty diagonal bands, about a quarter to half an inch wide, three to a side, are harder than the surrounding metal, as evidenced by the fact that they project slightly from the surface (were not ground down as much during (re-)polishing). The hada within the stripes seems to flow in the direction of the stripes, whereas to either side of each stripe are big, round itame pools. The quality of the blade is not very high, but I just thought I'd mention it since it does appear to have been made from a billet with a harder metal twisted around it, for whatever reason.