Following the iron brush

Hi ,

Becouse i'm learning, I have some issues that may seem simple ,
but I would like to hear from more experienced views?

I manufacture swords for practitioners of martial arts, which often use their piece for training, cutting, etc. ....

How to fix the sword is given only for the "sandwich" of habaki, seppa, tsuba, seppa, fuchi /kashira and locks of mekugi,in the impact of cutting it suffers a considerable pressure .Mainly in habaki in the area hamachi and munemachi.

Most ancient swords that i can see have slackness ,mainly in habaki ( hamachi an munemachi bash ) and tsuka ( by the wood shrivel).

I thought that the more close the adjust , less the chance of future slackness.

Is some post's Ford taught that the tsuba is not necessary to nakago ana fit close the nakago shape ,and it is very close can damage the "mei" and "togi".
To adjust it the pieces of copper : sekigane fit in the blade, ok ."I did not know this " thanks Ford.

What about the habaki, seppa and fuchi holes???? is larger than the nakago shape.

There should be a diference in the assembly of a blade to traditional collection or to cut ?????


Many thanks
,

remo

No difference between collection or pratical intentions; everything passed trough centuries keeping a simple sandwich sistem.

As you pointed out, is it true that the habaki is important; in fact it is the most important part of all the koshirae.

Yet, it is not completely true that habaki is a stressed part during cut.

When you cut with the blade, the impact point stress reaction in fact is your hand. your hand gives and recieve force trough the contact between nakago and the inside of the wooden (honoki) tsuka.

The tsukamaki keeps everything togheter. In fact, if you mount a sword inside a not glued tsuka, and you try to push down the sword tip area into a wood block, you will notice that the tsuka will open. Apply the force of glue and tsukamaki and you will keep it closed. Is important to build everything in the most accurate way as possible, so that the stress will be very well distribute in all the parts of the mounting. Leave a weak point, and it will probably become a break point.


PS: This is a very complicate question, including stress study, force dynamics and so on. Please, everybody, feel free to reply if you think i wrote some stupid point; of course i can be completely wrong

Thanks Lorenzo,

What about the habaki, seppa and fuchi holes???? is larger than the nakago shape.??


remo

The habaki must be formed directly on the nakago that will fit it. It is close to the nakago shape, just that little bigger that allow the habaki to be extracted from the blade.

The fuchi hole is always larger; also seppa, even if you can do seppa holes a little bit closer to the blade. Nothing shall touch the blade except the habaki, tsuba sekigane tsuka wood and the mekugi.

This picture is far more clear than my words:

Ok Lorenzo,

Thank´s for the information,


Remo

Great post Lorenzo!

I went to reply, but i really cannot state it any better then what you have already said, and pictures speak a thousand words (as "they" say).

A side note. I read a post by an American togishi about a pet peive he has when polishing swords and fitting habaki. From time to time he ends up having to totally reshape the nakago of some swords so that the habaki can actually slide onto it, which can be a problem if the maker has already signed it. One of those things that a person might not think about when making/finishing a blade. Just something to think about for those that are taking up sword smithing.

-Donovan

That is a very annoying problem for anyone that has to make Habaki. I work primarily with western made blades and each smith goes through this phase where there nakago are badly shaped early on. It takes time for them to get enough feedback to correct the problems since most work in relative isolation. The Nakago is the last thing to receive focused attention on the priority list.
The Nakago problems primarily are thick swells forcing one to make the habaki large enough to get over these swells. When they finally slide in place they are quite loose as a result. This should not happen on a new blade. Even when the Nakago is fine the signature's are often done in such away that burs have been raised quite tall. I have seen some sigs that increase the measured thickness of the nakago by a full millimeter! Another annoying issue is the departure angle of the Mune. Sometimes the nakago mune takes off at a steeper angle from the Machi. This gives the blade an awkward kinked appearance. This can be so pronounced that the back of the Habaki ends up too thin or poorly shaped to accommodate the issues.
It seems that almost every time I work with a new smith's blade I end up fighting the shaping issues or replacing a poorly shaped smith made Habaki. That is the nature of the beast here in the modern western sword world. It is annoying and some smiths do not welcome feedback unless it happens to be praise.
patrick

no! ...I can't believe that

I know, I know, I was shocked too!
Those smiths won't be posting here much
patrick

Good points Patrick,

realy a bad shape nakago is a problem, sometimes a thin/sharp hamachi cut the habaki in use .

thank's,

remo

One more pratical questions,

The copper is a soft metal , a good shape habaki realy don't shrink in the use?
If positive, are some notice of other more hard metal used in atique pieces.


thank's

remo

some very old examples of iron habaki exist. kamakura period.

I had to rise to this bait. The tanto below is from a while ago and despite not being entirely happy with it, I still plan to finish it, starting with making a habaki.



For that, I use 1/8in thick copper sheet. After tapering the copper and wrapping it around the nakago, I was working on fitting the habaki when it suddenly decided it no longer wanted to come off. I had missed a slight swell and now get to repeat several hours of foundation polishing. I did that inspite reading about the virtues of a properly shaped nakago from you

As time permits, I hope to be posting here more.

Thank you,
Niels.