Is Saiha Always A Bad Thing?

[paulb]

This might appear proof that Bowman is sinking fast in to senility but bear with me and think about it.

This started with a conversation I had with Darcy a while back. I think we agreed that the key to any sword is the steel. The really top rated smiths work always, without exception start with high quality steel and superb forging. Once these are right all other features (except shape I accept) develop automatically out of the characteristics and composition created in the metal when it is forged.

This is why so many people, me included, believe the very best swords were made in the Kamakura period when iron and steel production was localised. While many Shinto smiths had great skill they did not have the very fine material available to a number of koto schools.

With this background I would like to consider something else. Whenever I have seen “saiha” on a description I immediately turn off my interest. I have always believed that the act of re-hardening a blade removes many of the features seen in the original work; it changes the shape, the texture of the steel the size and look of the nie and more and more.

However let’s take another point of view. The Echizen smith Yasutsugu was a favourite of the shogun of the day. One reason for this is he was tasked with re-hardening masterpieces that had suffered fire damage in various military encounters. He did this very well. The question that came up in conversation was” were his saiha works better than those he forged himself using modern materials” (remember he was one of those who incorporated namban-tetsu in to his own work)?

The key here is how well the saiha is carried out. It would need to be done by someone who understood the original work and how to reproduce it. But the benefit would be that the starting point, the original steel would be of a quality that lent itself to recreating the key features.

So given the choice between a saiha Soshu masterpiece sympathetically re-hardened by a Shinto master and one of his own works using Shinto steel which would be best? Or more importantly which would you choose?

[Gasam]

Heyas,

And if someone was expert in saiha, would they mark the nakago as saiha, or could they perform the rehardening without creating excessive sori, dry flat looking steel, and without the water shadow? If so would we even know thet rehardening had taken place?

[Jean]

3/4 years ago, there were at DTI a saiha Sadamune retempered by Yasutsugu and its utsushi by Yasutsugu, both Tokuju. The Saiha was for sale 180k$ and the utsushi 250k$.

[paulb]

Well the honest answer is I dont know, but the key is how well they do it.

A number of highly regarding koto and shinto blades exhbit Mizukage (water shadow) so it's presence alone should not necessarily be a game changer. My biggest concern would be the effect on ji-nie chickei etc and whether the quality and subtlety were lost. The nakago could be re-patinated and shape adjusted.

As suggested in the OP the key is that it hould be well done by someone knowing what they wre attempting to emulate. If they could produce a good copy using newer material you would guess they could do a pretty good job on the original.

I dont recall ever seeing a high quality example hence the question but I dont think you can take a blanket view "all saiha are bad" if they were why bother doing it on important swords?

[Gasam]

Heyas:

 

I think if say your Sadamune was ruined in a fire, that would be unacceptable. Saiha then would be bad compared to having the original, but far better than having what basically now is a Sadamune blank. You would want the person you thought would best do the original justice to perform the saiha.

 

Interestingly, there is a film on youtube about a sword smith making a sword for a shrine, he performs yaki-ire on the blade without any clay, trying to recreate an old type of (i belive) choji hamon. He fails the first time, only part of the blade is satisfactory after initial polish. He reheats and performs yaki-ire again. This time he succeeds and the blade is polished fully and presented. I would think, technically, that is also saiha, but in this case for a better result, and therefore desireable. But still saiha. Or am I mistaken i calling this saiha?

[CSM101]

This is an example for a very big NAME-saiha.

 

Uwe G.

[Alex A]

.

So given the choice between a saiha Soshu masterpiece sympathetically re-hardened by a Shinto master and one of his own works using Shinto steel which would be best? Or more importantly which would you choose?

 

I would need to see them both in hand

 

Once re-hardened though, its fair to say that the sword by the soshu master is no longer the sword by the soshu master.

 

In that case, I would find it difficult accepting a saiha masterpiece with a big name (not that I can afford it).

 

Same price though and I may be tempted

[SAS]

Once the steel has been heated to forging temperature, it has no memory of what it was before. IMO, the only reason for excessive curvature on a rehardened sword would be that the smith did not straighten the existing curvature prior to yakeire or temperature was excessively high. Mizukage is a function of how the sword was quenched. If competently done, no trace of the saiha would remain.

[ROKUJURO]

I want to underline Steve's comment and add from my own experience that to prevent too much SORI after SAIHA, you have to heat up the blade a first time and straighten it. As heating up to the necessary temperature inevitably produces a material loss by surface oxidation, some smiths might be tempted to quench the blade in its state (without straightening it) which then can end up with more SORI than in the original blade.

In an effort to produce an UTSUSHI blade with similar HATARAKI one has to know precisely how the smith in question had been working with his clay (TSUCHI-OKI). You need to know the temperature of the cooling water which was a big secret in former times. The quenching temperature of the steel is not so much a mystery as this has to be around 800°C, otherwise it would not work.

So straightening a blade plus re-hardening plus a good polish is only an option if you have a really beefy blade without any KIZU like hidden FUKURE, SHINAE or so. 

In any case, SAIHA will always result in a blade that is reduced in thickness.and width (and possibly altered in the SUGATA as well) and thus not be perfectly like the original.

[flemming]

Hi There all

I find hada to never appear fully as original in terms of chikei thickness, intensity and "realism". The pattern is the same, however unless every detail of the original yakiire is known, bake time, bake temp, quench temp etc, the hada will be altered from its original appearance. Here is another yaki-naoshi (saiha) by another big name, but since it is common in Hizen swords many of you will have seen this hada in hand, or reasonable photos. This was konuka hada of Omi-dai-jo Tadahiro ca 1640 or thereabouts. This is not the same quality of the konuka usually seen in the Hizen swords, the saiha is apparent, at least in my opinion. You can also see a ghost of the original hamon, this blade was originally suguha. The mizukage was moved behind the habaki with a machi-okuri operation, then nakago repatinated to hide it, something probably reserved for expensive swords. It would be interesting to know who did this work to the Tadahiro, it is not a terrible job by any means.

 

Lloyd Flemming

[ROKUJURO]

Lloyd,

in principle, the HADA cannot be changed except when excessive polishing removes the KAWA-GANE. This can be the case especially in blades that have a respective KITAE with very thin 'skin-metal'. 

[Darcy]

Late to the thread. Some clarifications:

 

1. The Yasutsugu utsushi is one of several he made of Sadamune in general. The target of this utsushi is the meibutsu Shishi Sadamune. The Yasutsugu in question is Tokuju but there are 5 others that he copied of this exact same blade that are Juyo. There were surely other copies made. So he seems to have applied himself strenuously to the task of replicating this sword. This one apparently has been singled out as the best of all the efforts. The Meibutsu Shishi Sadamune is Juyo Token in spite of being saiha. It's possible that Yasutsugu made all of the copies before attempting to work on the hamon of the Sadamune. The copies show some variety in approaches to the hamon like they are models, and he would probably look at them afterward and decide which one was the one to go with. One of them is an "after the fact" inspirational work that derives from the Shishi Sadamune. The one that went Tokuju does not have the hamon that he settled on when he made the hamon for the Shishi Sadamune. There are fine nie from the yakiba to the ha that are not present on Yasutsugu's work in general.

 

2. Hada patterns won't change but the steel composition in them will. Chikei are formed from ji nie merging and these are martensitic steel formations following higher carbon steel layers. Every time you heat and quench you will have a different variation in the appearance of ji nie and chikei though the steel itself will have the same pattern. If you took a Norishige and say had me retemper it by watching youtube videos on how it's done I am quite sure I would not see the same chikei (if any) or any of the other vibrant hada effects seen in his work. The jihada instead would become grey and lifeless but still have the same basic forging pattern. If you give it to Yasutsugu though with experience and who seems to on really serious work plan it out with various models and test the results, then it may get a lot closer to how it was in the beginning. Swordsmith skill is needed to get anything at all, but what he is doing is reverse engineering a result. If he does what he normally does with his talent on the steel of a Sadamune, a Yoshimitsu, or whatever, his results tends to be better than how it looks on his own swords because he's using a much higher quality base product as his starting point. But without knowing the exact method of the smith who came before him, the best he can do is try to guess and estimate and maybe make fully finished sword models to explore theories on what to do before he makes a try on the famous burned blade. 

 

I like Yasutsugu a lot. I think his work shows Sai-jo skill. Fujishiro holds him down one notch from top level and Yamanaka swipes him at some point too.

 

He though was working for customers who were highly dictating what the results should be. And they may not always agree with the aesthetic that someone coming 400 years later would have liked to see. But he is very clearly the early Edo swordsmith who has not one but two powerful sponsors that he needs to please and he can't even live in one place anymore. That they both wanted him and engaged in this tug of war over his work indicates that he was highly respected at this time. And I think he just had to make stuff to spec more often than make stuff to please himself, the things that Kunihiro and Tadayoshi could do after exploring all kinds of different approaches.

 

The guy was constantly being told to copy this and copy that, retemper this and retemper that, make this for the Shogun, make this for the daimyo. I just don't think he had the freedom due to the people who were asking him to do these things, that other smiths had.

[Darcy]

"Too much sori after saiha." I have seen this talked about before in books and here and so on but nobody has offered the mechanism for how this happens I think.

 

We can see in video that the martensite formation in the ha and pearlite in the rest of it causes the sword to curve. Martensite takes up a bit more volume. When you heat the blade though and turn it all back into uniform steel of some sort this volume change is negated. Carbon migrates out and you don't get martensite after you heat it up and let it cool down slowly. This should reverse the curvature induced by the first creation of the hamon. 

 

I don't think if you keep retempering the sword forever it's going to turn into a circle. I don't buy the forever bending blade because I don't see how the steel in the hamon can continue to grow in volume, which would be necessary to further curve the blade.

 

What CAN cause the blade to curve more though is say if you took a blade that is old and polished and has something like a very narrow suguba hamon. As this blade polishes out it will start to stoop forward. Losing its curve. This is one of the reasons that is claimed for uchisori appearing in Kamakura tanto that were made straight after finishing. We are told they are made a little uchizori going in, because the creation of the hamon will push back and straighten the blade. So, this is just the blade reverting as the hamon is polished away, to the shape it had before tempering.

 

So now you see this blade not with the original curvature it once had. If you replace this ito suguba with a chu-suguba then yes this blade will curve more than it was when you just saw it 10 minutes before the retempering. But if you put it in again and temper on a thinner suguba it shouldn't cause the blade to curve again, even more, it should straighten somewhat after the process. 

 

But if you keep doing this eventually you run the risk of the blade failing and a hagire developing.

 

I just want someone to pose a mechanism where if you temper a sword 10 times it will keep bending and becoming more steep. So, I don't buy that a deep curve is a sign of saiha. 

[SAS]

If you reheat a sword with existing sori without straightening, it will retain its curvature, but the martensite will be converted to austenite or some other softer structure. If you then heat it to the critical temperature and water quench, the steel will be converted back to martensite or other harder structure along the edge, which will induce curvature. interestingly, quenching in oil causes reverse curvature.

[paulb]

 

Darcy wrote:

Hada patterns won't change but the steel composition in them will

 

I think this is one of the points I wanted to confirm and explore. I think there are two basic apsects to consider:

 

1. Although the structure remains the same the composition will change. Although activity in the jihada is facilitated by the original steel composition and welding, the size, shape brightness of such activity as ji-nie chickei etc is created when the blade is heated and quenched. If this is done by another hand then the end result is likely to be different. I would guess that those with experience, knowledge and skill can get closer to the original if that is what they are trying to achieve. I would also assume that in the case of re-quenching a famous blade that would be the intention.

 

2. The other question which I accept is subjective is would a re-quenched high quality koto blade be a better sword than one made by the same smith using later steel?

As suggested I dont know how one could go about proving it but if old steel was measurably better than later material one might assume that the requenched blade would also be better.

In support of the old steel theory there are many examples of later smiths going to great length to use old metal (old nails, tools swords etc) and reworking them in to new blades. I assume they did not do this for fun, although it may not be based on more than fad or marketing rather than practical benefit.

[ROKUJURO]

......In support of the old steel theory there are many examples of later smiths going to great length to use old metal (old nails, tools swords etc) and reworking them in to new blades. I assume they did not do this for fun, although it may not be based on more than fad or marketing rather than practical benefit.

Paul,

 

this has to do with the fact that steel, made from iron sand and coming out of a traditional TATARA, is usually very pure and has no other alloy partners than carbon (except some trace elements like titanium). Any addition of elements may (and will) change the properties of the steel and will require different heat treatment procedures.

 

In former times, there was no other method in Japan but the TATARA, so there is a kind of 'purity' guarantee if you use 'old' steel/iron. In nEurope, modern type blast furnaces started to produce large amounts of iron already at the end of the Middle ages, so this could be exported. But it was not the same quality as the TATARA steel, although these early blast furnaces were still charcoal-operated. I am convinced that the Japanese KAJI did not use a high percentage of NAMBAN TETSU in their blades, and it was mainly for the exotic effect (or marketing, as you mention) and for easier or cheaper purchase that they did so. 

 

I am working with pre-industrial steel in my workshop, and this material is considerably different from modern steel and requires different techniques.

 

 

[paulb]

thank you Jean

I think you are confirming what I had been told previously and I agree about the amount of foreign steel used for effect rather than function although availability may also have been a key factor.

 

thanks

Paul