Edo Period Cast Tsuba

[Larason2]

There have been many posts recently (and also in the past) regarding cast iron tsuba in the Edo period. As Ford Hallam has argued in the past, and then again recently, it is unlikely that any authentic Edo period Japanese tsubas were cast, and there is no actual evidence that they were. However, strangely, there still seem to be a lot of forum members who disagree with him. So this post tries to explain my view of some of the misconceptions about the technology involved, and problems with terminology that I think are contributing to the problem.

For one, I think it is important to remember what cast iron is. It is iron that is melted, that is brought to its liquid phase, then poured into a mold in the liquid phase, then allowed to cool. Below is the phase diagram of iron:

 

https://fractory.com/iron-carbon-phase-diagram/

 

As you see here, on the X axis is the proportion of carbon mixed with the iron, and on the Y axis is the temperature. An important point is that unless the carbon is something pretty close to 4%, you have to heat the iron significantly higher than the melting point at ~4% to get fully liquid iron, otherwise you’ll have liquid iron with some precipitates. 2000F, or 1130C is already very hot, and difficult to get iron to, so having iron with a mixture of different carbon compositions makes it significantly harder to cast iron. I’ve read you actually have to get it quite a bit hotter than the actual melting point, probably because it is just too viscous at the melting point to pour.

 

Therefore, at the temperatures at which it is reasonable to cast iron, it is still quite viscous. As a result, when they pour it into the mold, similar to maple syrup, it actually picks up quite a bit of air. Because of this, it makes cast iron quite porous, that is, filled with air bubbles, and this is what differentiates it from other kinds of iron. Because of that, the only actual way to tell by looking or feeling a cast iron piece that it is actually cast iron is to see the evidence of air bubbles, or to find a defect where the roof of an air bubble broke, and left an air bubble hole. Another obvious sign that something is cast is a sprue mark. That is, an irregular, elevated spot on the side of the piece that marked where two pieces of the mold met.

 

One previous poster said that annealing is a sign of cast iron, but this is not true. Annealing is just heating the metal, and it can be done to both cast or non cast iron. Another said that evidence of rework is a sign of cast iron, but if you work cast iron, you open up bubbles, so by definition cast iron can’t be worked or reworked unless you’re ok with bubbles showing. Others have said that cast iron has a typical surface texture, but again, you can get a similar surface texture with both cast and non cast items, so that isn’t a reliable sign. One other poster showed an image of an extensively rusted tsuba that was broken, and claimed the fact that it was broken is an obvious sign it was cast, however if we recall rusting weakens iron. If rusted iron breaks, why are we assuming it was casted when it could have just broken because it was badly rusted? Another poster said that the definition of the mei is a sign that it was casted or not, but again, this could be carved to have softer lines or not regardless of what it was made out of. Even the brittleness of the material isn’t actually a good sign of what kind of material it was made out of, since there are all kinds of casting that can produce an output of various kinds of brittleness, all kinds of annealing/alloying and other processes that can strengthen cast iron, and cast iron itself can in fact be worked until it is wrought iron, in which case it will cease to be brittle.

 

So what you should do if you actually want to know what cast iron looks like is to go to your local thrift shop and pick up an old cast iron frying pan. Look at its sprue marks, and if you can’t see any obvious bubbles, then just scrape it with a chisel until you do. Then you will know what cast iron looks like, and you will be able to feel what cast iron feels like.

 

Now we have problems with terminology. There are some people that call any kind of iron with a carbon content over ~2% cast iron. The problem with this is that there are many kinds of iron that have a carbon content over 2%, but have never been cast. If it has never been cast, then why are we calling it cast iron? It is also improper to call it castable iron, because technically any iron could be cast if you heat it up enough. The problem there though is that the technology to do so is not always available, and it definitely wasn’t available in Edo period Japan. Next, there are some Japanese terms that are mistranslated. For instance, the term “zuku.” It is sometimes translated as “cast iron,” but in practice, it is any iron that has a relatively high carbon content in it. For instance, after the tatara process, a kera is produced. That kera was never heated up enough to fully melt all of the iron that was smelted, and it ends up producing iron of many different kinds of carbon concentration, including some that have a carbon concentration above 2%. It is not right to call this cast iron, because it has never been cast. The parts of the kera suitable for making a sword, which we call tamahagane, are removed from the kera, then other metal makers take what is left. Sometimes this “zuku” is worked until it becomes malleable (so therefore becomes wrought iron), but sometimes it is fed into the ohkajiba process, which is basically a sort of early puddling furnace. This process also produces malleable, or wrought iron, but again, it has never been cast, so it isn’t right to call it cast iron. 

 

Now during the Edo period in Japan, most of the steel that was used came from the Tatara process, with some modifications. The Japanese government viewed the provision of smelted iron to the population as a matter of public service, and so they supported it. There was a small amount of foreign metals that the Japanese imported, probably even before the Edo period, but they are not of much discussion, because the whole point of the Edo period was isolation from the rest of the world. Also, whatever metals they obtained, they used them in the traditional ways. 

 

Now, we know that the Japanese also did some iron casting, and that this took place before the Edo period. An important and very culturally relevant example is the casting of tetsubin (or iron kettles), which took place significantly before the Edo period. Here is an interesting video that is quite relevant:

https://www.youtube.com/watch?v=pqrJC8D3eEs

 

As you can see, the point of casting here isn’t to make a cheap and fast product. The first step is going around to garbage cans, back alleys, and thrift shops to find as much “old iron” as possible, since the tetsubin makers know this is the best iron for their process (presumably because it is the product of the ohkajiba process, and the carbon content is more compatible with a full melt). Then, they laboriously hand carve a sand mold, then use it to make no more than a handful of tetsubin, because if they make any more, the quality of the product will suffer, and as the tetsubin maker said themselves in the video, they don’t sell anything unless it meets their standards of quality. So obviously, this isn’t a cheap and fast way to make throw away products. Also, it doesn’t make sense to heat up the metal to over 2000F to cast it, if they can just carve a tsuba from the base metal much more easily anyway. 

 

Another point is to discuss Chinese casting. Many forum members have made the point of saying that nanban tsuba were cast. However, in my opinion there isn’t actually any evidence on the pieces that have been presented proving definitively that they were cast, as I discussed above. The fact that they were extensively carved actually argues against the casting hypothesis, as I’ve mentioned before that this would open up air bubbles in the iron. The Chinese also had a puddling process since the third century similar to the ohkajiba process called “chǎo” (炒), that was quite effective, so if they wanted to make the tsuba out of wrought iron, there is no reason why they wouldn’t have. It’s also clear to me from the quality in general of the nanban tsuba that they were actually also hand made, and produced by Chinese artisans that cared about the quality of the product, and not an attempt to flood the Japanese market with cheap knock-offs. If we consider them inferior today, it’s only because their workmanship isn’t quite as good as the beautiful Japanese models we’re used to seeing on NMB, not because their workmanship isn’t actually good. The Chinese used cast iron extensively, for instance for tea kettles or decorative statues, but they didn’t use it on products that isn’t compatible with cast iron, and I would think a tsuba, or anything else that is subsequently going to be worked or carved, is a good example of a product that isn’t very compatible with cast iron. Because of problems with translation, we may have even eminent Chinese scholars saying nanban tsuba were cast iron, when what they really mean was that they were made from high carbon iron, and may have well been wrought iron. It’s not enough to say it was casted from that translation alone, since neither Japanese nor Mandarin Chinese have enough subtlety in the language to differentiate whether smelted ore was actually cast or not. 

 

To illustrate some of the challenges with translation, I’m going to look at the Japanese and Chinese words for iron. In Japanese, iron is referred to as “tetsu” (鉄). The word for cast iron is “chutetsu” (鋳鉄), with “chu” meaning “cast.” Wrought iron is “rentetsu,” (錬鉄) with ren meaning “wrought,” but that not being a word that is otherwise used in Japanese. The character “zuku” 銑, is translated by google translate as “pig iron,” however, this doesn’t make sense, as the Japanese didn’t use blast furnaces, nor cast iron as pigs for further processing, because iron sand would just be blown out by a blast furnace. 

 

In Chinese, the word for iron is “tiě” 铁 (in traditional, 鐵). However, a word for both pig iron and cast iron is zhùtiě 铸铁, with zhù being the word for “cast.” There is another word for pig iron though, which is Shēngtiě 生铁, which literally means “raw iron.” You could see how this could be used to refer to any other raw form of iron though, such as malleable iron produced by a puddling furnace. The word for wrought iron is “duàntiě” 锻铁, which literally means “forging iron.”

 

Given all these words and their varying meaning, it’s easy to see how even for Japanese and Chinese speakers, the subtleties of what technological processes produces what kind of product and what it can be used for can easily be lost. There is obviously no different word to differentiate iron produced by the puddling process from cast iron except wrought iron, and it wouldn’t be surprising if someone just used cast iron for both, as they do in English. While there are words for cast iron and wrought iron, there isn’t really the subtlety to say something like high carbon iron that hasn’t been cast. 

 

Finally, I think we have to remember what a privilege it is to have someone like Ford Hallam actually take an interest and post messages in a forum like this. As many of you know, but clearly not all, Ford is a master tsuba artisan. He has won 8 gold medals in the national Japanese tsuba competitions from his original work, and is probably one of the world’s foremost tsuba experts. While this does not mean he can never be wrong, we should perhaps emulate the Japanese a bit more when it comes to showing respect for a master who is commenting on a matter in which he is an expert. Having tsuba books, having owned and looked at tsuba under a microscope and listened to the uniformed opinion of other tsuba owners on a forum for a while is not equivalent to Ford’s hands-on experience, the depth of his knowledge, and his obvious skill. If the Japanese government were to execute a tsuba assessment service similar to the NBTHK, it is someone like Ford who would sign the papers.

 

All this being said, if we can see a single authentic Edo period iron Japanese tsuba with a sprue mark or an obvious air bubble, then it will definitively prove Ford and myself wrong. That’s how science works. Until then, I think we should respect his authority on a matter in which he is an expert.

[Dan tsuba]

Hello Carlos!

 

What an amazing post!  Thank you!  

 

I may not agree with everyting you stated, but your research and in-depth knowledge is much appreciated.

 

Again, just a wonderful and fascinating post full of great information.

 

With respect,

Dan

[Brian]

[Dan tsuba]

Hello all!

 

As Carlos stated in his (wonderfully done) post.

 

“There have been many posts recently (and also in the past) regarding cast iron tsuba in the Edo period. As Ford Hallam has argued in the past, and then again recently, it is unlikely that any authentic Edo period Japanese tsubas were cast, and there is no actual evidence that they were. However, strangely, there still seem to be a lot of forum members who disagree with him.”

 

That is correct Carlos, and (as many members know) I am one who disagrees with him.  Now, I am not going to argue with members (that doesn’t get anybody anywhere!).

 

But I would just like to bring up the following as an area of interesting information (well, at least I find it of some interest!) and something that may be considered by some. -

 

I referred to the Suzuki Morihisa cast iron studios in one of my threads.  I purchased a beautiful cast iron bottle opener from them and showed close up photos to compare the surface texture to some tsuba (and “no” I haven’t used it to open any beer bottles – It is just too beautiful to use if for that!).

 

That post can be found here-

https://www.militaria.co.za/nmb/topic/38416-tsuba-casting-molds/page/8/

 

 

This is information for the cast iron studio-

“SUZUKI MORIHISA 鈴木盛久

Established in 1625, Suzuki Morihisa is one of the oldest Nanbu Tekki foundries in Iwate. Together with four other master casters, the first generation Suzuki was invited to settle in Morioka by the ruling Nanbu clan and played an important role in the foundation of Japanese cast ironware. The family business is now in its 16th generation and is the holder of two notable firsts in the history of Nanbu Tekki: the 13th generation being appointed an Intangible Cultural Property of Japan, and the 15th generation as the first female caster in Iwate. Suzuki Morihisa continue to preserve traditional techniques through their robust ironwork that can be used today and across many generations to come.” (from below weblink)

 

https://www.sunday.de/en/nanbu-tekki-suzuki-morihisa-square-trivet.html

 

 

Now, if you check out their catalog of cast iron items (in the below link) there are some very nice cast iron artworks in it.  To me (at least) some of the cast iron items could look similar to tsuba.  Picture from part of the catalog included at the end of this post.

 

https://morihisa.stores.jp/?page=2

 

 

Some of these cast iron items are so beautiful (at least to me) I think I need to purchase a couple of more different items (after I get my next Social Security check!  Ha, ha, ha, ha, etc!)

 

The adventure continues!

 

With respect,

Dan

[b.hennick]

I appreciate the work/effort that has occurred in making this thread.

As I read each post, most lead to thinking about the main points made.

Threads of this level should be elevated in some way so that the thread can easily be found by new and current members. 

Perhaps we need a section of threads of outstanding merit where these threads can be accessed easily. 

Would it be possible for members to vote for such threads? There could be a minimum number of votes necessary to elevate the thread. 

[Spartancrest]

1 hour ago, b.hennick said:

threads of outstanding merit

Simple -  vote ten 'hearts'  =  gets a post upgraded? My vote is in!

[1kinko]

I’ve melted a lot of copper but not iron. The melting point of copper is 1981F (1083C) and the melting point of iron is not 2000F, but 2802F (1539C). However, it takes a little higher temperature to actually pour molten metals, in my experience.

[Larason2]

1kinko, yes you are right in a way. The point on the phase diagram at 2000F is the point at which cooling iron solidifies for a different carbon composition, which is different than the melting point. However, they are related in that melting point is also affected by carbon composition, just as the solidification point is.

[1kinko]

Agreed. My point was more related to the proposition that Edo period tatara reached temperatures that produced molten iron/steel or “cast iron”.

[Dan tsuba]

Hello all,

 

So, it seems that (once again) a discussion on the possibility of cast iron tsuba in the Edo period has strayed into the subject of the temperatures needed to melt cast iron.

 

And, once again, it seems that the tatara could not reach the necessary temperature.

 

But we know that the Japanese craftsman had the technology (as early as the 1600’s) to melt iron into the making of tea kettles.

 

Now, what type of furnace they used for this melting process (whether a modified tatara, blast furnace, or some other type of furnace) is interesting but maybe suited for another thread dedicated to that subject?

 

I know that this subject of furnaces and temperature has already been discussed on that “Tsuba casting molds?” thread, but I am not going to research all 10 pages of that thread to find the answer!

 

I just consider it a foregone conclusion that the craftsman during the Edo period had the technology to reach the desired temperature for melting the cast iron and then pouring it into molds (as evidenced by the making of cast iron tea kettles).

 

I don’t know, maybe I am “missing” an important point somewhere?

 

The adventure continues!

 

With respect,

Dan

[Larason2]

As I mentioned before, 2000F is the melting point of iron that is about 4% carbon. That is the point where you start getting some liquid iron in the mix of different types of iron. It will still overall be solid though. The bits of iron that melt are the smal pieces and atoms that are not molecularly bonded. However, you still have to overcome the intra molecular bonds of many kinds of iron, so iron at 2000F will not flow, and is not castable. As you see in the phase diagram, the melting point of iron varies depending on the carbon concentration. If the carbon concentration is 2%, there are different kinds of intramolecular bonds present, which will inhibit a full melt more. Even if you manage to get the iron warm enough to run and pour, that doesn't mean there aren't still some solid iron molecules left in the mixture. In Japanese cast pieces, these grains of iron, carbon, and other materials that have not yet melted are desirable, and are thought to contribute to the artistry of the piece. So they just heat it up until it flows enough to cast, the exact temperature is irrelevant to them, but you can count on that it isn't hot enough to fully melt everything that is present. 

 

The same occurs in the tatara process. Iron sand isn't just pure iron present in rock. It's mostly iron molecularly bonded to other substances with strong ionic bonds. Some of that iron, say iron oxide, is relatively easy to overcome the bond strength with heat, others, say iron silicates, have a very strong bond, and you have to get the iron really hot for it to melt. I don't even think that 2802F is hot enough for some of the compounds, such as silicated iron, especially if the carbon concentration bonded to it or nearby is really low or really high. If it's a small enough component, it won't matter, the iron will still flow. Such iron is "castable," but it's not fully melted. You need to get iron insanely hot for it to fully melt, at which point it will start to boil off the carbon, and then it will cast as steel. That's why it's a bit pointless to talk about the "melting point" of cast iron. It's a huge range that depends on  a very wide range of variables. 

 

As mentioned before, the tatara process is not hot enough to fully melt all of the compounds in the ore. But it is hot enough to melt some. That's why the tamahagane and zuku looks like it does. I've seen temperatures given for the process, but giving a fixed temperature doesn't make sense. There are temperatures for whatever brief period that can melt low carbon iron, so that must be pretty hot. The heat is not evenly distributed though, so it doesn't fully melt the iron. The proof of this is when you look at a piece of split kera. It has all kinds of obvious impurities in it. It doesn't look like cast steel. Remember that silicon and titanium are some of the desirable impurities in tamahagane. 

 

Here's the chemical information for iron carbide:

 

https://www.americanelements.com/iron-carbide-12011-67-5

 

You'll see, it's melting point is about 5684F!

 

[Larason2]

Here's titanium carbide: 5740F

Here's silicon carbide: 5130F

 

 

 

[Dan tsuba]

Thanks, Carlos, for your scientific and detailed explanation.  You make me feel as though I need to return to the university, and this time acquire a degree in metallurgy!

 

However, I have a question.  My question is “during the Edo period (or even maybe before that period in Japanese history) did the Japanese craftsman make tea kettles from cast iron that they poured into a sand or clay mold?”

 

I believe the answer is probably “yes”, since I can find some very nice cast iron Japanese Edo period (at least that is what the description states!) tea kettles on the internet.

 

It seems to me that the metal must have been heated enough to make it pour easily.  In the video referred to in your fist post to this thread (link below) the heated metal looks like it is easy to pour into the mold!

 

https://www.youtube.com/watch?v=pqrJC8D3eEs

 

Now, in the video above they probably use a different furnace than what was available to the Edo period craftsman.  But the artistic results and craftsmanship of the finished products still appear quite similar!

 

So, again they evidently had the technology to do this.  They also seemed to do this on a regular basis.

 

Thoughts or insights?

 

With respect,

Dan

[Peter Bleed]

This discussion truly is interesting. And I certainly don't wish to argue with true experts. But, there is no question that a wide variety of cast iron objects were made and use in Japan in late Edo times, various vessels, roof tiles, agricultural gear.... Making these things involved hand finishing and removal of sprues etc. This is work that peasants in Iwate-ken did to avoid starvation.

There were as well, guys who needed to wear a sword from time to time, but who could only  afford mass-produced cheapos like the cast iron tsuba we see today.

Peter

[Toryu2020]

History of Tetsubins (calacademy.org)

 

The adventure continues...

 

-t

[Toryu2020]

Japanese cast iron: history, benefits, products, and brands (booniehicks.com)

 

800 years of history?

 

-t

[Toryu2020]

900 years...

 

The Genuine ‘Nanbu Tekki’ Kettle - Morioka, Iwate - Japan Travel

 

-t

[ROKUJURO]

Thank you Thomas,

for the links.

While the wrong non-Japanese plural "TETSUBINS" conveys some lack of competence in my eyes, the text names the kettles correctly as "water kettles". You cannot make tea in iron kettles. This seems to be unclear to some.

[Dan tsuba]

Thank you my friend Jean for joining this thread!  

 

And as you have stated before in some previous threads, the correct usage of cast iron kettles is "water kettles".  I just can't seem to get it through my "thick head" that they are not "tea kettles"!  I don't know what is up with that!  I will try to use the correct terminolgy in the future.  Thank you!

 

The adventure continues!

 

With respect,

Dan

[ROKUJURO]

On 4/15/2023 at 9:29 PM, Larason2 said:

.....it is unlikely that any authentic Edo period Japanese tsubas were cast....

For one, I think it is important to remember what cast iron is......

 

Therefore, at the temperatures at which it is reasonable to cast iron, it is still quite viscous.....

....As a result, when they pour it into the mold, similar to maple syrup, it actually picks up quite a bit of air. Because of this, it makes cast iron quite porous, that is, filled with air bubbles, and this is what differentiates it from other kinds of iron...... 

 

....One other poster showed an image of an extensively rusted tsuba that was broken, and claimed the fact that it was broken is an obvious sign it was cast, however if we recall rusting weakens iron. If rusted iron breaks, why are we assuming it was cast(ed) when it could have just broken because it was badly rusted?....

....cast iron itself can in fact be worked until it is wrought iron, in which case it will cease to be brittle.....

 

....The character “zuku” 銑, is translated by google translate as “pig iron,” however, this doesn’t make sense, as the Japanese didn’t use blast furnaces, nor cast iron as pigs for further processing, because iron sand would just be blown out by a blast furnace. 

 

All this being said, if we can see a single authentic Edo period iron Japanese tsuba with a sprue mark or an obvious air bubble, then it will definitively prove Ford and myself wrong. That’s how science works. Until then, I think we should respect his authority on a matter in which he is an expert.

Hi Carlos,

while I consent with many valuable information that you gathered in your long post of last Saturday, I would like to make a few remarks on it.

Firstly, it may be important to note that it was not denied that casting an iron TSUBA was possible in EDO JIDAI. When water kettles were cast, there is not much doubt that casting a TSUBA would  have been technically possible. The question was if it was really done in numbers "for the masses of buyers" (who were they?) at that time, as is believed by some.

You are correct in that 'cast iron' is the term for melted iron that was poured into a mold. But how would you call the iron just prior to casting? It has the properties of cast iron, so I think it is not completely wrong from the chemical side to call it so.

In your description - as well as in most other related posts - there is no mention of important details of the casting process. There was iron heated in the TATARA and then poured into molds?  No, you need to have refractory containers to store and move the liquid iron, and you had to have means to get the molten iron out of the furnace (which had to be very different in construction in comparison to TATARA) into these transport containers! It is a completely different technology compared to a forge!

As was already mentioned, the temperature ranges were different, as melting iron was much too demanding. I have mentioned before that a part of the TATARA output was low-carbon iron, a big part was steel with differing carbon content, and one portion was carbon-rich iron with the properties of cast iron. That means it could not be used in a forge with traditional methods. I also reported that this material was used by swordsmiths in OROSHIGANE furnaces together with scrap iron to make suitable steel for blades.

This 'cast iron' was a material source for casters as its melting temperature could be as low as 1.200°C. A thin-walled water-kettle could only be cast with low-viscosity molten iron, so you can be sure it was well heated and liquid!  

In later times it was absolutely possible to cast iron with almost no bubbles, and when you look at many cast TSUBA, you will find that they are quite well made, looking at only the surface. In my opinion, this points to the well developed casting technology of a later time than EDO.  

Surface rust on an item will not necessarily provoke failure. This will only happen on very thin items that have almost rusted through.

There is no mention of how you want to "work" cast iron until it becomes wrought iron. Do you mean puddling or drip decarburization? Really "working" cast iron on the anvil does not result in usable metal.

When you wrote that the 'iron sand will be blown out if used in a blast furnace', you possibly forgot that the gas/air pressure is used in the molten metal. It makes no sense to pump air into the iron sand!

 
 

[Larason2]

Thanks Jean for adding your insight.

 

As I mentioned in my first post, the Edo period Japanese had iron casting technology, and were able to get iron hot enough to flow smoothly. The furnaces a modern tetsubin uses, if they are doing the work traditionally, are the same as they were in the Edo period.

 

Therefore, it's true that Edo period Japanese could have cast a tsuba, particulary the tetsubin makers, but that doesn't mean they did. As Grey mentioned once in another post, tradition is very important in the nihonto business, and it is also very important to the Japanese (though it was more important in the Edo period!). Tsuba are traditionally made from malleable iron and carved, and tetsubin are cast. The craftsmen kept up the tradition for hundreds of years, and did it much the same way as their ancestors did. Their market only really bought traditional goods until the end of the Edo period. This may not make sense to a western person, who always wants to buy the newest and greatest, but it made sense to the Japanese. This sense of the importance (maybe even sacredness) of traditional objects is part of what brought us the nihonto. I think we have to try to understand Japanese culture if we want to understand how and why they did things like preserve so many 600 year old swords when in Europe they just kept making new and different ones. At the beginning of the Edo was the advent of many technologies and social movements such as Christianity that most Edo Japanese felt destabilized the country. This influenced what they produced and what they bought. 

 

One part of this is trying to understand the culture. One interesting tidbit is that practically no one in asian cultures like Japan is left handed. If a child expresses a preference for using the left hand, they are taught to use the right, and not allowed to use the left. There's a sense that a certain way is "right," and there really isn't tolerance for deviation. It's actually possible to make a kettle out of wrought iron, but it's harder to prevent it from leaking. If that way is inferior, then why would anyone do it? In Japan, I think this argument makes more sense to people than it does here. 

 

A similar sense occurs in China. When a medication was withdrawn from the market not long ago, it was withdrawn at the same time by every manufacturer. The reason is hypothesized to be because in reality, one company in China makes all of it, and it is then just packaged differently for the different drug companies. For us this doesn't make sense, but for the Chinese it doesn't make sense to produce the same drug twice when they can just make enough once. 

 

Dan, the pictures you linked are nice, but lets say you went to a table at a market, and you saw three traditional hand carved tsuba on one side, and three obviously cast iron tsuba on the other, and they would all be the same price. Which would you buy? Now, the likelihood you'd pick one or the other is also culturally determined. In Japan, they put a strong value on conspicuous consumption and highly value tradition. It's like a wagyu restaurant in Japan. My brother looked at one when he was there, but he found the prices were very expensive, whereas you can also just get wagyu from a street vendor! So they went to a street vendor, and they said it was amazing. The restaurants also have nice beef, but the patrons are also going there to be seen. The items sold by Morihisa are all items that are compatible with cast iron. They do not try to make a shovel or a rake, for instance. The use directs what is made, and how it is made. 

 

We used to have craftsmen in Western culture, but they have all but dissappeared. A friend of mine is restoring a 1890's house in Edmonton. The wiring was all before code, and there were some nasty bits like live wires with wall current sticking out of the roof! She had something like 10 electricians come to look at it, but none of them wanted to do it. Finally she found one close to retirement who these days only does interesting projects like hers. Those who are craftsmen are hard to find, but they have a vision about how things are supposed to be. It would be a cold day in hell the day Ford Hallam decides to make a cast iron tsuba! So the tsuba makers of the Edo period, who ate and drank and slept and breathed tsuba, and who had as their holy grail the great tsuba makers of the past and their present didn't really make cast iron tsuba. There was a pride and an honour to that. Now they're dead, but people like Ford Hallam keep their work alive. And we have a special respect for that, including their choice of materials. By the way, in Japanese tsuba means "collar."

 

In the west, they've been making cast bronze and brass hand guards for hundreds of years. They are recognized to be inferior to steel and non cast guards, but no one cares. If you're a western military blade collector, you're lucky if a blade has ever been oiled. The Japanese, however, put a very high importance on the maintenance of their possessions. A good example of this is the fact that a lot of Japanese still use carbon steel knives. If you've ever had a carbon steel kitchen knife, you'll know that if you cut a grapefruit and leave it on the board, it will rust with red rust in something like a minute. The Japanese always have a towel or cloth at hand to dry it so it doesn't rust. The Japanese also wash their bathtubs after every bath, and they bath daily. Overall their culture of maintenance is much more developed than it is in western culture, and it is linked to buying the best of a given item, rather than just what is cheapest, or what works. 

 

If Ford Hallam was to accidently misidentify a cast tsuba for a non cast one and vice versa, it would ruin the replica tsuba if he tried to make it. One does not earn 8 gold medals in the national Japanese tsuba competition and be unaware of this detail. When he sets out to replicate a tsuba, it's not enough that it look identical, he also has to, to the extent possible, also use the traditional methods. When he has taught us how to make tsuba, he says that before you do anything, it is important to meditate on what you're doing, to more get into the mind of the tsuba's previous creator than anything. Then, when you're certain that what you're going to do will result in the exact results of the tsuba you're copying, then you can proceed. It's more channelling the original maker than making it yourself. Ford is working on a copy of one of kaneie's masterpieces, and it is amazing both how gorgeous it is, and how faithful it is to the original so far. This is a result primarily of the philosophy, which Ford lived and breathed for many years. You should see how well he speaks Japanese!

 

The same goes for togishi. After ten years of apprenticeship, living and breathing nothing but polishing, there are things that just don't make sense. If you brought them a koto and told them to polish it Edo period style, they would probably decline the commission. Even in the Edo period, they knew how koto swords should be polished, and they only polished them that way. This artistic continuity is integral to all the Japanese arts, and its strict observance was more important in the Edo period, when Japan was closed off to the world.

 

Now Peter says that in the Edo period (and probably before), there were cast iron items that were used and modified by peasants. I would think it is unlikely that they trimmed off sprue, but it is possible. Indeed, a tetsubin maker also trims sprue and finishes a tetsubin (which Jean correctly identified is only for water). But again, only certain classes of items were suitable for cast iron. Maybe they "worked" them, but as I said above, if they worked them too much or the wrong way they would break. If you look at the lovely items Dan posted above, you can see none of them have any obvious signs of work. To some extent, it is a sign of a deficiency of a cast iron item that you have to modify it to make it functional. By attempting to modify it, you take a risk. Sometimes you try it and it doesn't break, but sometimes you try it and it does. Just try to cut a tsuba out of a cast iron frying pan, and you will see what I mean! As I mentioned, extensive work is evidence against casting, because of this risk, but it doesn't make it impossible.

 

So what we have here is that an item such as a tsuba is a product of a distinct culture, and the beliefs, practices, and philosophies of the people affect the outcome, and also affect how the item is produced, and how they become available. In addition, the details of the technologies available and the science of the materials also affect the forms in which an item can be found. To work within a tradition, it’s not enough to just find out how to make something, you also have to live and breathe and understand intimately that tradition. Those modern businesses who make cast tsuba don’t really get that. They want to make money, and they know that people will buy certain tsuba, so they cast them. Some of the cast replicas actually look quite nice. However, they don’t function as tsubas, and those people are unable to make tsubas that have a new or different design that fit within the tradition, because they don’t understand it, but Ford Hallam can. In the Edo period, they had different technology, different beliefs about tsuba, it was a different time and they had different philosophies. As a result, the goods they produced had a particular form. That doesn’t mean it’s impossible for there to be cast tsuba, but Ford Hallam and I think it’s unlikely, and this is both because there isn’t any evidence of it (based on Ford’s assessment of a very large number of authentic tsuba), and because it doesn’t make sense with Japanese culture and the history of the Edo period.

[Larason2]

Thanks for your long post Jean!

 

In terms of what to call molten iron just prior to casting, you are right that it is a matter of terminology. In fact, people can and do call things whatever they want. However, sometimes this leads to confusion, and that’s why I propose we only call “cast” materials that were actually cast. As has been shown in my above posts, the same product of smelting can be used or subjected to other processes, and the materials properties may be different (for example, wrought iron vs. cast iron). Calling wrought iron cast iron in this context doesn’t make sense, since they are different materially and chemically. There is probably some other wrinkle in the translation from English to German and vice versa, though I'm not very well versed in German!

 

You are right that cast iron has different technology than other kinds of iron. For the Tetsubin process, they have a special refractory container as you mentioned to heat and hold the liquid iron, which they then poured in the mold. The actually getting the iron hot enough to make a tetsubin is one of the most time consuming and difficult parts of their work, and it doesn’t always go as expected (it seems to depend a lot on the iron they melt). The Chinese also had similar processes, as well as possessing larger refractory containers that could be tipped onto a sort of casting bed with channels to move the liquid iron to different areas to be cast. As mentioned by yourself and I, the tatara process is incompatible with casting. However, parts of the kera produced by the tatara process could be fed into the ohkajiba or chǎo process to make malleable iron. They probably wouldn’t have been able to just add zuku to the casting container though, since the carbon concentration would be so variable.

 

As you mention, the melting temperature for some “cast iron” can be as low as 1200 degrees C (~2000F). As I mentioned though, this is only true for relatively pure iron with a carbon concentration of ~4%, and a low level of impurities with a high melting point. So trying to cast with Zuku from the tatara process would have probably been impossible. 

You are also right that in modern times it’s possible to cast iron/steel with no bubbles, but I also agree with you that this technology probably didn’t exist in the Edo period. 

It is true that rust does not always lead to failure, it has to rust through. Rusting does structurally compromise iron though, so it is easier to break if it is extensively rusted. My point though was that rusting through is a process that can lead to failure, so a broken item that shows a lot of rust could in fact be made from something other than cast iron. It’s also possible to break wrought or malleable iron without rust! So we can’t use that as a criteria from which to declare something to have been cast. 

 

I believe it is true that you can “work” cast iron until it is malleable. However, it is not something that pretty much anybody will do today, because it is incredibly frustrating and time consuming. As you know, when you heat up cast iron and try to work it on an anvil, it will break into small pieces and crumble all over the floor. However, if you diligently keep picking up those pieces, and keep heating them up and hammering them, they will, after a very long period of time, become wrought iron. This is because the only difference between what you start with and what you end up with is the length and structure of the particles of iron. It’s not surprising though that there were technologies developed to produce wrought iron more easily! We know there was wrought iron since the bronze age. The technology used then was bloomery iron, and the bloom that you get out of a clay bloomery furnace has a lot of impurities, is very brittle, and crumbles a lot when you hammer it. Keep at it, and you’ll get wrought iron though, and the process is the same (with a lot more frustration!) with cast iron.

 

When I was talking about iron sand and a blast furnace, I’m just talking about the incompatibility of a blast furnace with iron sand. All smelting that uses charcoal requires oxygen to work, and in the tatara furnace, it is provided by clay tubes coming into the side. In a blast furnace, the air is forced into the furnace by bellows. Blast furnaces are incompatible with iron sand because when you add the sand, it will get blown out when the bellows force air into the smelting chamber before it smelts. This is why the tatara process was necessary in Japan, where they could have just adopted the blast furnace technology of the Chinese.

[ROKUJURO]

Hi Carlos,

another - not much shorter - reply!

.....As you know, when you heat up cast iron and try to work it on an anvil, it will break into small pieces and crumble all over the floor. However, if you diligently keep picking up those pieces, and keep heating them up and hammering them, they will, after a very long period of time, become wrought iron. This is because the only difference between what you start with and what you end up with is the length and structure of the particles of iron....

I tried to process cast iron pieces packed in an iron container. It was a long process of trying to forge and reheating. In the end, the involved labour was in no good relation to the result. Hammering cast iron and picking up the crumbs is possible, but not heating up. The crumbs will either fall through the coal and end with the slag, or they will simply melt and get lost, because the temperature interval of cast iron between "softening" and melting is quite small.  

.....the bloom that you get out of a clay bloomery furnace has a lot of impurities, is very brittle, and crumbles a lot when you hammer it. Keep at it, and you’ll get wrought iron though, and the process is the same (with a lot more frustration!) with cast iron....

No, that is not my experience. Bloomery iron is quite ductile unless you have those pieces that were exposed to more heat (near the vent tubes), have taken up a considerable amount of carbon and have turned into a kind of 'cast iron'. They are not malleable. Bloomery iron is rather pure as it does not contain alloying elements and only small amounts of impurities (silicates from the slag, possibly sulphur and phosphorus which can be eliminated in the refinig process). I have run a number of Celtic style bloomery kilns and always have some of the iron in my forge for demonstration purposes. With the spark test, I can show the inhomogeneity of the material.

....When I was talking about iron sand and a blast furnace, I’m just talking about the incompatibility of a blast furnace with iron sand. All smelting that uses charcoal requires oxygen to work, and in the tatara furnace, it is provided by clay tubes coming into the side. In a blast furnace, the air is forced into the furnace by bellows. Blast furnaces are incompatible with iron sand because when you add the sand, it will get blown out when the bellows force air into the smelting chamber before it smelts.....

The air forced into the contents of a blast furnace with bellows (charcoal or mineral coal) is used to oxidize the carbon of the pig iron. This is a chemical process that only works with the molten metal, not with the dry SATETSU. So it will of course be possible to add iron sand to the molten metal without the risk of it being blown out. The air pressure would never be as high as to 'lift' the iron up! Bellows were used in all types of furnaces in pre-industrial times, but in some places the Celts used bloomery kilns with 'auto-draft air supply'. This works with especially designed kilns and if the surrounding conditions were favourable; i.e. building the kiln on a slope and having constant strong wind from one direction.

It may be of interest that modern iron making processes use a different technology in that the molten iron is transferred into a converter where it is treated with high-pressure oxygen to oxidize impurities and unwanted elements. Temperatures up to 3.000°C are attained.

[Dan tsuba]

Hello all!

 

Some very interesting information!  Thanks to all for some great posts!  And also, thank you Rokujuro (Jean) for separating known facts from opinions on some metallurgical processes.  You made a difficult subject (at least for me!) somewhat easier to understand.

 

So, what I get out of all this is that the technology was in place during the Edo period to make cast iron tsuba in sand or clay molds. 

 

Now, whether this was ever done is still an area of debate.  As has been referred to on this thread and that “Tsuba casting molds?” thread there is no “hard” evidence of a cast iron tsuba being made in the Edo period.  Although on that “Tsuba casting molds” thread there were pictures shown of “papered” tsuba from the Edo period where specific areas were pointed out as perhaps having gone through a casting process.

 

It was also stated in a previous post to this thread-

" It would be a cold day in hell the day Ford Hallam decides to make a cast iron tsuba! So the tsuba makers of the Edo period, who ate and drank and slept and breathed tsuba, and who had as their holy grail the great tsuba makers of the past and their present didn't really make cast iron tsuba. There was a pride and an honour to that. Now they're dead, but people like Ford Hallam keep their work alive.”

 

Well, the statement “So the tsuba makers of the Edo period, who ate and drank and slept and breathed tsuba, and who had as their holy grail the great tsuba makers of the past and their present didn't really make cast iron tsuba.”

 

Personally, I find that a very well written and stated opinion.  And that is all it is, because it is not a proven fact!

 

Also, “‘It would be a cold day in hell the day Ford Hallam decides to make a cast iron tsuba!”

 

Why?  I think that it would be a valuable experiment to conduct, and many questions could probably be answered regarding the making of cast iron tsuba.

 

In the end, it is as I have stated on many threads regarding cast iron and forged iron pieces.  I will reiterate something like it here.  “The only way to ascertain for certain if it is made from cast iron or forged iron is to subject the piece in question to non-invasive (or even invasive) scientific metallurgical analysis.  Otherwise, everything else is just an individual’s “best guess”. 

 

Until they make a “cheap” way to do the above-mentioned analysis, I figure I for one will just keep guessing!

 

Oh well, all this makes for a very interesting thread!

 

The adventure continues!

 

With respect,

Dan

[OceanoNox]

16 hours ago, Larason2 said:

They are recognized to be inferior to steel and non cast guards, but no one cares. If you're a western military blade collector, you're lucky if a blade has ever been oiled.

Quite untrue, that. It is documented, at least for British soldiers, that many officers changed the blades and guards to suit their needs, i.e. switch brass guards for steel ones (as opposed to their issued swords), and there are enough well preserved blades to show that clearly they maintained them well.

 

16 hours ago, Larason2 said:

Overall their culture of maintenance is much more developed than it is in western culture, and it is linked to buying the best of a given item, rather than just what is cheapest, or what works.

Also a humid environment that will quickly lead to rot, mold, and rust if proper maintenance is not done.

 

16 hours ago, Larason2 said:

By the way, in Japanese tsuba means "collar."

Sorry, can you expand on that? I have found it written "止め刃", and "都美波", or "刀盤", but none of them seem to mean "collar".

[Spartancrest]

 ツバ (Tsuba)
saliva noun    鍔, 鐔
Kana Reading つば

guard on sword, polearms, etc.; flange   [Flange could also mean metal collar?]
Parts of speech meaning: brim; visor (e.g. of a hat) 唾液, 唾

 

https://www.wordhippo.com/what-is/the-meaning-of/Japanese-word-b533119613a3eded5d358c3ebdbbc8a8a182d91f.html

https://www.nihongomaster.com/Japanese/dictionary/word/41651/tsuba-鍔-鐔-つば

[Bugyotsuji]

Dale, some of those lines above are out of synch and actually confusing.

 

The sound 'Tsuba' can and does usually mean 'spit' 'saliva' or 'drool' to most people for example, but written 唾 ( as right at the end of your quote above). 

[Bugyotsuji]

1. spit, noun    つば　唾　saliva 唾液 (daeki)

 

2. 鍔, 鐔 Kana Reading つば

guard on sword, polearms, etc.; flange   [Flange could also mean metal collar?]
Parts of speech meaning: brim; visor (e.g. of a hat)

 

Like that perhaps?

[OceanoNox]

1 hour ago, Bugyotsuji said:

2. 鍔, 鐔 Kana Reading つば

guard on sword, polearms, etc.; flange   [Flange could also mean metal collar?]
Parts of speech meaning: brim; visor (e.g. of a hat)

The different writings I gave all come from Mr. Sasano's book on the origin of tosogu (刀装具の起源 · 著者 笹野大行, 1979). I have personally never seen them written other than つば, 鍔, 鐔. I still feel that collar is the wrong translation, and that fuchi actually means collar.

 

If I may add my own opinion on the topic, we are back to what Dan has written above: unless we can actually perform some measurements, density, hardness, chemical composition, etc., or find clear records of those times, we will continue arguing about the possibility of them having been produced. At the moment, it seems there are none in existence, except perhaps some of the namban tsuba, according to Lissenden's work in 2002 (http://etheses.dur.ac.uk/4129/1/4129_1648.pdf). There is little else, and destructive analysis might be the only way to prove anything.

As has been said about oroshigane, there was (still is, industrially, stainless steels in particular are mostly made from scraps) a culture of recycling of iron items. This itself is also an issue when discussing tsuba or other historical artifacts: are the existing antiques representative or exceptions? There is a record of farming tools being repurposed to make tsuba in the Edo period. Iron items without further use were processed by oroshi to make "new" material.

 

P.S.: I try to follow expert opinion. If there is data that makes it fact, all the better.

[Bugyotsuji]

Arnaud, I was not answering your post, but Dale's, and I was not talking about possible definitions in English.

 

If we confine ourselves to the Japanese written Kanji for a sword Tsuba, then yes, you are correct.

 

If however, we approach more broadly from the sound of the word 'tsuba', as Dale did, then it has other meanings including 唾 with a mouth radical, unrelated to sword guards. 

 

As to possible meanings of 鐔, 鍔, notice they both have the metal radical on the left.