Tamahagane experience

[Carlos Lara]

So, I went ahead and bought 30 kg of tamahagane from Japan. Not that I need it, but I was very curious about how it would feel under the hammer, and how it would forge. It's also nice from a creative perspective to have different steel sources to work with. The plan is to use it to make blades and fittings with it eventually, the first step was to sort it and try some of it under the hammer! There's been other posts about it here, which were helpful. Since smiths don't buy it every day, I thought I would share my experience. 

 

Sales in Japan to western smiths are now taken care of by "Kameya." Here's the link:

 

https://kameya-english.square.site

 

It's a bit complicated. You need to go to the "paperwork" part of the page, then there is a part that says "click here for email inquiries," then you fill out the form on that page. You receive an email from "kogaology (at) gmail.com" (comes up as "remystique biz") to discuss the purchase. If you haven't ordered before, they recommend you get the "random" tamahagane, which has all the different grades of it that are present in the "kera" bloom, and the recommended starting size is their 30 kilo box. This made sense to me, because I want to learn about it and experiment! It's not cheap though, about $300 USD for the 30 kilos, plus expensive shipping. I paid also about $400 USD for the airmail, but you can get it down to ~$100 USD if you take the "general transport" option, which probably involves ship transport, and will probably take months to years. They also had a fairly expensive handling fee of ~135 USD. Still, this is the real deal tamahagane! While I know it's just a form of bloomery iron, it still is very interesting to me because of the history of Japanese blades.

 

Anyway, it all arrived very stoutly packaged in a double cardboard box reinforced with nylon straps, nylon ropes to help carry it, and the goods were packed in the type of plastic bag that steel won't just shred (though it had some holes!). Here's a picture of it laid out:

 

It's actually pretty straight forward to identify at least three different types in person, though it's harder to show in pictures. At least on visual inspection, there's three grades. On the left is the "tamahagane," which looks like bits of metal stuck together, with colourful oxidation visible on some parts. The stuff in the middle looks about half iron, half coal dust, and the stuff on the right looks like more melted coal dust/bits of coal/slag with a small amount of metal in it. Haven't tested it all yet, but I'm guessing the stuff on the right is zuku (high carbon content), possibly the stuff in the middle too. While they said what they would send would be random, really about a third of it was what looked like "tamahagane," and the other two thirds the various high carbon content looking stuff.

 

So today finally put a piece of the "tamahagane" in the forge, and I found what you would expect, that it works a lot like wrought iron (at least the piece I tried, maybe some of the other similar looking pieces will work differently). As it heats up to yellow, you start to see some bubbling, which is presumably carbon and other impurities. It responds to the hammer nicely, though it is definitely slightly stiffer than the wrought ship chain I was also working on. I didn't have time to try a lot of different pieces, since I was more focusing on making some wrought tsuba blanks for now and chisels for chasing, but I will in time and report back. My plan for the tamahagane at first is to make a small blade to cut my teeth. Hopefully I'll get in a few more forging sessions before it gets cold, I don't have the equipment to run my forge in the snow!

[Alan Longmire]

9 hours ago, Carlos Lara said:

you start to see some bubbling,

 

That's the trapped slag, you get that in all bloomery smelted irons/steels.

 

9 hours ago, Carlos Lara said:

definitely slightly stiffer than the wrought ship chain

 

Because it's high carbon steel.  But you knew that, I just threw that in for those who aren't familiar with this stuff.  

 

How far are you going to refine it? What people think of as "number of folds," that is.  The more times you cut, stack, and reweld it, the finer the hada, but also the lower the carbon.    

[Joshua States]

Cool stuff. I'm completely fascinated by the small batch smelting process. I would really like to see what your processing looks like.

 

[Carlos Lara]

Thanks Alan! Yes, it's high carbon (though it's still a mystery for the moment just how high it is!)

 

I'm going to try for folding the 10 times on the first blade! It's not going to be huge, so it shouldn't take too long! 

 

Thanks Joshua, maybe I'll try a video to show a bit of the processing.

[Aiden CC]

Interested to see how this turns out! $10/kg is by far the lowest I have seen for tamahagane, usually its 10-20 times that. It may have to do with receiving different grades. I imagine there isn't as much demand for the lower carbon parts of the bloom and areas with poorer consolidation as these days the blooms are only used for super high-end stuff.

[Emiliano Carrillo]

Shimane made tamahagane is largely too uniform and high carbon to create the visual seen on old swords. I got a box of the mixed grade stuff from the sisters as well as some of the higher grade material, and the higher grade stuff was ornery and cracked often, which is something I've never had happen with my own steel. The lower quality material had more character and a better carbon content when finished. I've successfully hardened my own steel at over 1% carbon before without any trouble, being able to straighten cold from the water, and not had any issues. But as soon as I used the shimane tamahagane it would just not behave properly. So I guess just take that with a grain of salt. Most of the smiths I've seen working it, and famously the Yoshihara, tend to work 50% shimane and 50% self made oroshigane into their pieces, and sometimes less shimane steel. I would imagine that the lower quality material will be more interesting the finished and have a higher chance of survival. I spoke with an old master named Kunio Izuka and we discussed the shimane tamahagane at length, and we agreed that the way steel was made in antiquity, with local small batch bloomery production being the norm, was more inline with the differences seen between schools and smiths of different regions, and that it was largely why the modern swords don't have the same look as very old swords do.