Smelting wootz

32t

Active Member
No Victor, crucible smelts can be done in portions of hours depending on the system. For wootz dendrite formation, it takes a slow cooling overnight to room temperature.

Tamahagane in the large legendary furnace runs upward of 72 hours. The master smelter stays awake the whole time likening it to helping birth a baby. Everyone helping gets to run in shifts if they have enough people.
I do not understand the ego that a "master" would have that they can stay awake for 72 hours and make reasonable decisions without mistakes.
 

Bruno

Administrator
Staff member
I do not understand the ego that a "master" would have that they can stay awake for 72 hours and make reasonable decisions without mistakes.
I've seen the process on film. It's not so much ego, but more the fact that he is the one responsible for the result and if he would take a break and things go wrong... It's not so much that he needs to make continuous decisions. He needs the be 'there' at least partly for the sake of being there. Like the national flag.

When it comes to Japanese people, a number of things are done just for the sake of it. My teacher says that the head of the company she works for is Japanese, and a large number of people working directly under him are Japanese. The head guy makes it a point to work no later than 6. Of course he continues work from home in the evening, but he doesn't stay late because it would make it impossible for the people under him to go home. Because you get to work before your boss, and leave after him. Even if you're not doing anything useful.
 

Mike Blue

Member
I do not understand the ego that a "master" would have that they can stay awake for 72 hours and make reasonable decisions without mistakes.
Quite literally, he's "the guy." The traditions dictate his participation. I've worked with him and he's quite modest about his position. He is a well educated metallurgist who readily admits that traditional smelting is making the point the hard way. His day job is working for Hitachi Metals. I've operated a couple short stack smelters with him watching over a couple weeks when he came to the US for demos at the Univ of MN. For the big smelt in January, all the sword smiths in Japan depend on him for their base materials. A lot rides on his shoulders.

Hmm, I really don't know how to tell the story, but more than anything his spirit infuses the place. The art students were almost paralyzed with him overseeing the process. But they were in awe of the special person and unsure of their own abilities. They kind of stalled and he had to jump in to show them what to do a lot. I just got to work. He never really moved into my space, but clearly had everything I was doing under observation. He asked me a lot of questions but never told me to do anything differently. The Japanese (of his kind) are all about the spirit of the human being as able to influence a physical non living object. I had a great feeling about him, he felt good about me, it was all going to work out.

If he wasn't prepared or willing or was in a bad mood, it would affect the outcome of the steel. His spirit affects the people on the team. You don't see stuff like that in modern industrial processes. They would never let someone like me (gaijin) near the big smelt as I would "stink up the steel." He knows well that I'd find a peephole to watch through and that nothing about me would really mess things up. It's more for the other superstitious types who really worry about such things. Any other days of the year, I could do whatever I chose to in his shop.

He's as worried as most teachers are in Japan. The traditional crafts simply cannot attract new apprentices. It's a big chunk of time to work on subsistence wages doing all the drudge work for a master-crafter. Heck, they can't afford to pay an apprentice much less house you and all you bring with you. When he dies, the knowledge goes with him. I'm a cup he poured some things into so they wouldn't get lost.

One element still impresses me. The professor hosting everyone had this big blackboard and they wrote down the time of every charge, the weight of iron and charcoal, when they added a little chicken grit to juice up the slags, etc. I kept a little notebook for about an hour and then went native. He'd come over to check on my burn and asked why I wasn't taking notes any more. How did I keep time? Well, I breath about six times a minute so 60 breaths or so, it's time to add material, but if I'm watching I had this level just inside the stack that was low enough to add materials. How did I know how much iron to put in and how much charcoal? I had to interrupt him to unplug the taphole and got a nice flow of liquid slag and plugged it up again. How did I know that was the time, he asked?

I said that I was listening to the fire. It was burbling a little and needed to clear its throat. So, how do you balance the air flow? I listen and adjust the air until it sounds smooth like a flute, get rid of the off-harmonics and correct the tone to be on-key. That earned a big smile from him. As to the charges of iron and charcoal, after an hour I have a pretty good idea of how much is right by seeing the stuff in the shovel we were using rather than measuring every little gram. Later he grabbed me and had me follow him over to another of the student stacks. That one sounded like it was gargling. He made a big show of coming over to my stack and holding a hand behind his ear for all to see him listening and to compare the two fires. A couple of gestures by the man, and I got to explain all the rest in English. I had the students tap the slag hole and adjust the air and they starting running a lot better.

It's a science versus art thing. The old timers used to sing songs as a way to keep the pace. The retired prostitutes who operated the smelter's bellows would sing to regulate the air flow. There's a classic tamahagane song somewhere on the net and I can't find it.
 

Bruno

Administrator
Staff member
There is a big problem for the smiths as well.
The Japanese government only allows them to make 2 swords per month, and those need to be traditionally made.
At the same time, the people in Japan are only allowed traditional swords, because those are cultural artefacts, while a modern made katana is a weapon.

This hits the smiths coming and going. They are cut off from the international market for affordable swords, while the domestic market is kept small because of high prices. Starting out as a new smith in Japan is choosing a beggar's life. Only the ones who get recognized and gain a following can raise their prices. The number of suicides among smiths is skyrocketing, I have been told.

Japan is trying very hard to preserve the old ways. But it is doing it in such a way that those old ways are at risk of dying out, or at least of losing valuable master to apprentice transmissions.
 

Bruno

Administrator
Staff member
It seems I was wrong. Almost all spots on the list have been filled i, in a short amount of time.
 

Bruno

Administrator
Staff member
The class is still cancelled but I've been communicating with the guy who was to teach it. He uses a mix of pig iron and chemically pure iron like Alfred pendray. Only he needs to buy it by the multiple metric ton.

I bought 5 pounds of this mix to smelt myself with his advice. And he smelted a 5 pound ingot for me from the same mix. This way i have a reference to compare with.

He's also told me how to forge it down in order to maximise cementite activity

1621


1622
 

Bruno

Administrator
Staff member
This is still not happening. However i acquainted the guy who was coming over and was going to teach. He sold me the raw material and one of his own ingots from the same material for comparison.

He also gave me lots of good information on working it. On Tuesday it was an auspicious day so i started forging to his instructions.

That's a 5lbs ingot. Ideally i would have used a powerhammer but i couldn't go to my friend for that because the ingot also needed a soak for 4 hours so i used my press. Thankfully I had the foresight to have the hydraulics built with a bypass valve for the 2nd stage to get the speed out of it.

This is where i stopped for the day. Next I'll cut it in 2 and draw a piece out into a useable bar. And then forge some slices for testing the ht and etching

1773


1774


1775
 

Victor Creazzi

King of Bondo
It's my understanding that the ingot has to be rimmed (creating a layer of low carbon steel on the skin) to act as a ductile shield to keep oxygen from entering any cracks that develop during the early forging of the ingot, as the large grain structure as smelted leaves the steel vulnerable to developing cracks. It's talked about in that Pendray / Verhoeven video.
 

Bruno

Administrator
Staff member
I have been told by several people who knew him personally, that Pendray's own methodologies changed significantly over the course of the years, and that his SOP had changed a lot since that video. It is correct that as-smelted, the grains are coarse. After smelting and cooling down, we roast the ingot in a kiln. Niko told me to stay below 1000 degrees, for several hours. This has the effect of normalizing the ingot and removing some of the coarseness. Plus it guarantees that you start forging with the entire ingot at proper temperature.

From there I start forging and indeed, the first cycles have to be done very gently. I was told to forge at lower heat than normally. Which was relatively easy because coming out of the kiln at a known temperature, I had a color reference. Every forging cycle, the temperature goes up and down around austenizing temperature.

Even so, it's a slower process than forging damascus and I really need to make my press go slow. First time I tried this using a press, the ingot got squashed open like a grape. Thankfully it was only part of an ingot, and not an expensive one but it taught me the virtue of patience when forging wootz. Howard once told me he had the same issue with his hammer when trying to go too fast on a wootz ingot (way back when he got one to play with).
 

32t

Active Member
My thoughts when reading this is that maybe going old school with an apprentice or two with hammers would be the way to go.:p
 

Bruno

Administrator
Staff member
Ah no it is not folded. That's just a bit of frown, caused by the fact that the top was wider than the bottom. That frownish thing you see is is a slight fold. It's about 1 mm deep I just need to forge it smooth.
 
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