They started to build the tatara on Saturday the 12th and finished it by Wednesday the 16th (so you thought you could build that in a single afternoon ).

The original tatara, as you can find them in Japan are 3m long and 1m wide but since they only had 1 week time to build and operate it, they scaled it down to 1.30m long, 1m wide and 1.3m high.

Here you can see the charcoal they gathered to keep the furnace going :

This is how 3700Kg charcoal looks like

16 Big bags with a weight of 200-250kg each. So if we take our calculator, that’s around 3700kg total. At the end , they have been using ‘only’ 3000kg of it. This charcoal was made of pinewood in a traditional way. These are not the same as the charcoal we use to have a barbecue party.

That kind of charcoal is too heavy, can’t reach the high temperatures they need and is glowing too long.

The iron ore that has been used, Sishen (coming from South Africa), is exact the same as the Japanese satetsu when looking at the chemical components within it . The difference here is that the japanese satetsu is black and the Sishen obviously not. They had round 2000kg of ore but ‘only’ 1300 kgs has been used during this process.

Sishen iron ore

And off we go, they digged a pit, 25cm deep and light a fire to make it completely dry.

Making a first fire to get the pit dry

The pit is filled with small pieces of charcoal

pit filled with charcoal

Basic construction : to build the furnace, they used 250 fireproof stones, 500 Kg clay and 700 Kg sand (quarz).

top view

Bottom part of the furnace

Pavel is finishing the bottom part with clay

Done

The finished furnace, ready to go...

Thursday 17th, 9.00h…Katja Lohmaan-Hütte, owner of Lohmaan-Stahl, is activating the furnace.

Let it burn..

Pavel checking the vents

Time for a first check

The First slag is coming out after 17 hours

Slag coming out

During the second night (Friday to Saturday) there was “a sea of magma”

Magma

Saturday 12h, letting the slag out for a last time

Almost there

Saturday 13h, filing the furnace for a last time with ore

Filling the furnace with ore for the last time

Saturday 15.30h, starting to take the tatara apart. At first sight it didn’t look like a lot of steel was produced

Taking the tatara down

Hey…they did find a little piece of steel

The first piece tamahagane

With 1300Kg ore being used, the little piece was only a fraction of what was coming…The next piece they found was a ‘bit’ bigger and too heavy to get it out by hand so they had to use other equipment…

Time to get some help to lift the big chunks

There were 2 big blooms produced, one of 180Kg and another one weighting around 210Kg. Besides that they did found another 25-30kg in the furnace and after cooling down there was 20-25kg cast iron found at the bottom of the tatara.

The biggest blooms were taken to the forge, where a 1500kg (air) hammer was used to make smaller pieces out of the big chunks.

The 1500 kg air hammer

The tamahagane that has been produced was of an excellent quality. No slag, very little wholes and big grains.

After building the furnace (12hours/day) and working 55hours straight to operate the furnace (every 10-15 minutes adding 10Kg charcoal and 7Kg ore) they finally had what they were looking for…real tamahagane..

If you know all of these you will probably know more than your friends   I also need to thank Pierre for revising  all of the images (and correcting me along the way)  to make sure i’m not screwing things  up…

This is the overview, let’s dive into the details…

The kissaski (鋒) is the point of a katana. You can find them in different variations of length but mainly we have :

• Ko kissaski (小鋒) : small  point
• Chu kissaski (中鋒) : medium point
• O kissaski (大鋒) : big point

The kissaki in the picture above is considered  a Chu kissaski, something you will find on most of the production swords.

The Boshi (帽子) is the hamon that is running along the kissaski of the blade

The Yokote (横手) is the line that divides the body of the blade (ji)  with the tip (kissaski). It’s not just a ‘line’ like you can find on many production katana, it’s a change in geometry of the blade towards its tip. On a picture is very hard to see if there is really a change in geometry, it’s something you need to feel to be sure

The Koshinogi (小鎬) is the extension of the shinogi at the tip of the katana

The Fukura (フクラ) refers to the roudness, the curvature of the cutting edge along the kissaski

The Mitsukado (三角) is the point where the Yokote, shinogi and the koshinogi are having a party

The Shinogi (鎬) is the ridgline  that seperates the edge (ha) and the back (mune)

The Shinogi-Ji (鎬地) is the are of the blade between the Shinogi (ridgline) and the mune (back of the sword)

The Habuchi (?) is the line  of the  hamon

The Hamon (刃文) is the temper pattern along the blade it’s edge

The Ha (刃) or Yakiba covers the whole area between the Ha-saki (刃先) or cutting edge  and the habuchi

The Jihada (地肌) is the surface pattern of the hada. It’s the main part where you can properly appreciate the Jigane (地金) which is very hard to point at since the Jigane is the steel that maks the blade. So the Jigane is also present in the ha, shinogi-ji, tang, etc

The Hi (樋) is the groove in the blade. Here same story as with the kissaski, they  do come in various shapes and types. Lot of folks confuse the word Hi with Bo-Hi which is a certain type of Hi. Bo-Hi(?) can be translated as ‘Big groove while a Soe-bi(?) for example is a small, fine groove.

The Sakihaba (先幅) is the width of the blade at the Yokote

The Monouchi (物打) is the part of the blade that is most used for cutting

The very idea of working alone, at peace, retired in a workshop set in the countryside, nearby a fire, with steel only for raw material, doing a work that never ceases to bring renewal and wonder, delighted him very much and In December 2005 he decided to chase his dreams and took of to Japan to start his Smith apprenticeship.

Now, anno 2009, he is still living and studying there and his aim is to become a licensed (westerner) swordsmith in Japan.
To quote Pierre :

“I’m at this point where I have touched everything, tried every technique but haven’t mastered anything! It’s very challenging and stimulating at the same time.”

I’m not sure about you but I’m very curious in such a way of living and Pierre is willing to accept questions and doing an interview..so…
Wondering how it is to chase an living your dream, this is your chance !!

Put your questions (regarding Japanese Swords) in the comment box below, or in the box on the right side of  this video and we make sure they got included in the interview. If there’s enough interest, we might plan to do some other things as well

So what would you like to ask to PIERRE ?

War played a major part in Japan’s history and the people were always developing new types of effectively weapons, and protection armor. Their early weapons mainly consisted of bows, arrows, and swords, along with protective helmets and whole body armor and this helped to reduce the amount of injuries and fatalities throughout the wars they endured. Japan’s history spans back to thousands of years. The history of the emergence of the Samurai sword during the war battles for land that was between three tribes such as the Minamoto, Taira and Fujiwara during the 9th and 12th centuries A,D.

The Samurai people were known for their expert fighting skills through being able to fight while riding on horseback and on the ground. It was found that they practiced their battle strategies in an armed and unarmed practice scenarios. They focused on fighting using a bows and arrows with good precision in aiming and meeting the target. Throughout the 12th and 13th century they began to focus more on using swords to fight instead of using the traditional bow and arrow battle equipment such as the the spears and a weapon called the naginata. The use of the swords allowed for the knights to fight in close combat. The creation of the Samurai swords were during the period of 11th to the 13th centuries and in this time and age are priceless collectibles.

The Samurai people carried two types of swords which are the diasho, a shorter kind of sword that is between 12 to 24 inches in length and the other is a daito-katana sword which is a longer sword and measured more in 24 inches in length.

The Samurai people named their weapons as they felt that it embodied a soul of being warrior.
The Samurai sword is designed with an intent to be a sharper and tougher sword and has a curved blade. It is made with a combination of iron and carbon metals. The swordsmith focuses on using hammers, along with fire and water in order to shape the sword into the proper needed shape. The sword’s strength and sharpness is able to cut through all bones of the body. It easily became the most popular sword to use during on foot battle.

The Samurai people were known to be well respected warriors in ancient Japanese culture. The Samurai swords were a part of their wardrobe and in many ways were expected to wear it wherever they went. It was not only considered a weapon but also is related to the symbol of pride, and honor. The swordsmiths or blacksmiths were those that fit of noble standards and high class standing because they crafted these powerful swords that were the essential importance of the Samurai warriors.

Japan’s ancient history of the Samurai sword shows how the warriors were very much spiritually connected to their weapons and became one with their swords while fighting in the war battles.

Although some may argue this fact, it is very likely that he the most famous swordsmen that ever lived. He is famed for his battles, his distinct styles of swordsmanship, and he created a legacy that has out lived him by close to 400 years!

THE LIFE OF MIYAMOTO MUSASHI

Miyamoto Musashi was born Shinmen Takezo in Harima Province around 1584. There is some that argue the date and place where he was born. There are some discrepancies between the facts that we know, but for the purposes of our article that place and date works fine. We do know that he lived for around 60 years, and authored his book near the end of his life.

Here are some of the more notable events throughout the life of Musashi:

1. 1596 – At the age of 13 Miyamoto Musashi won his battle against Arima Kihei
2. 1600 – It is believed that Musashi fought in the battle of Sekigahara, on the losing side.
3. 1604 – Musashi wins Musashi has 3 matches with the Yoshioka clan in Kyoto. He also battled a Buddhist priest trained in the style of Hozoin-ryu.
4. 1612 – After a time of travel, and various duels, Musashi has his most famous battle with Sasaki Kojiro.
5. 1615 to 1621 It is believe that Miyamoto served at Osaku castle, and worked as a construction supervisor that this time.
6. 1630 – Begins to further his knowledge of the arts
7. 1637 – Plays an important role in the Shimabara rebellion
8. 1645 – Finishes his book Go Rin No Sho (The Book of Five Rings).

Obviously this is a brief overview of Musashi’s life. Along with being a famed swordsman in his time, Miyamoto was also an accomplished artist, calligrapher, and sculptor. Through most of his life he lived as a hermit, and spent his time studying Buddhism and the martial arts.

A LEGACY THAT LASTS THROUGH TO TODAY

Musashi was responsible for the Hyōhō Niten Ichi-ryū or Niten-ryū styles of swordsmanship. Near the end of his life Miyamoto also the authored the Go Rin No Sho which literally translates to “A Book of Five Rings”. The book was considered to be a swordsman’s guide to strategy. A complete English translation of the book can be found here.

Whether you believe Musashi to be the world’s most famous swordsman or not, one thing does stand. His influence on the Japanese arts has had a legacy that lasts right through to today!

In the tatara, it is the burning charcoal that supplies the carbon. These typical Japanese smelter is made of clay, about 5 feet wide, 48 inches tall and 15 feet long, where it’s walls are 10 inches thick.

One operating cycle of the tatara takes 5 days. One day to build the walls (clay and sand), 3 day’s to smelt and 1 day to remove the iron out of the tatara. In this 5 days process , they need about 13 tons of charcoal and 8 tons of satetsu (black sand) to produce 2 tons of iron and steel, which is called Kera.

About half of this Kera is composed of steel ranging from 0.6 to 1.5% carbon and it is this portion that is called tamahagane. Only Two thirds of the tamahagane is of a good quality. The rest of the Kera can be used for forging swords if another separated forging operation is done, this process is called Oroshigane, where carbon is added or reduced.

Every time Tamahagane need to be made, the tatra needs to be rebuild. Its walls must be build out of clay bricks. The mixture that is used to make the bricks does contain a large amount of sand (silicon oxide) which makes the tatra resistant to fire and melting.

Since the forging process of a sword produces a continues loss of carbon, most of the smiths like to start with tamahagane that has an carbon content of 1.0 to 1.5% to forge the kawagane (jacket steel).

A billet of tamahagane t from the tatara furnace is very big (as you can see in the video) and includes various qualities of steel. The big ‘rock’ of Tamahagane is broken into many small pieces to check the quality.

From here on the smith can choose the right pieces and start the forging process of this katana.

This very nice video is showing the process of making Tamahagane

Later on, in the beginning of the Momoyama period (1568-1603), there was the evolution of the Uchigatana into a pair of blades that could be worn at the waist. The large sword was called a katana and the shorter one a wakizashi. The blades of these swords had a wider hamon and appeared in a more flashy way than was known on the tachi swords. The steel was more brighter and shiny and the texture of the steel was different of that of the Koto (old school) blades. The were no longer recognizable as having come from one of the five main schools and are sometimes considered as the 6e, the Shinto school.

Blades that date back from the Meiji times are called Gendaito or modern swords. Many of these blades were mass produced for officers in the imperial army. A lot of these swords had no hamon and were of a poor quality. The had the shape and the look of the traditional swords but didn’t had any hallmark when compared to the traditional hand forged tamahagane blades. The were not differentionally hardened and didn’t show any interesting grain pattern or texture in the blade. When any kind of these swords are found these days, the government requires that they need to be destroyed.

To prevent the production of ‘cheap’ Japanese swords with no aesthetic value on a large scale, the Japanese government decided to regulate the making of real swords. Following rules are still in effect today:

1. Only a licensed smith can make a Japanese sword. The definitions of a katana : any cutting instrument with a blade over 15 cm (6 inches) with a hamon and a rivet hole in the tang.
2. A licensed smith can produce a maximum of two long swords (over 61cm or 2 feet) or 3 short swords per month
3. All swords must be registered with the police

Many smiths today can easily produce double and if they could register them, they could be making more money so this law is a burden on the younger smiths and in a lot of cases a barrier to attract new people to this craft.

The technology that led to the development of the Japanese sword originated in China and was brought to Japan in the 4e-5e century A.D. At that time these swords were known as chokuto and did have a straight blade. There are scholars that do believe that a lot of these swords were made in China. By the Heian period (794-1185), the Japanese smiths made great process in improving their forging techniques and the straight swords changed to curved blades.

The main reason for this (changing from straight to curved) was the fact that the warriors that fought from horseback were in need of a ‘slashing’, and not a ‘trusting’ sword. The sword also had to be slightly longer and light enough in order to use it with one hand. So the Tachi was born. A nicely curved blade (with more sori than the katana we all know now) tapered strongly from the base of the blade to a very small point. These swords are also worn with the edge down, where the katana are worn with the edge up.

The hamonline that was developed during this period was more broad and Ashi started to appear. Ashi are almost invisible stripes of soft steel in the area of the hamon (hardened adge) that help limit the extend of damage should the blade begin to chip.

During the Kamakura period (1185-1333), when Japan was under the rule of a warrior class, smiths learned to insert a soft core of low carbon steel (more flexible) into the blade. This process is know as lamination and had several different techniques were the kobuse lamination is the most popular.

In the Nanbokucho period (1333-1392), many swordmaking methods were practiced throughout Japan and could be divided into 5 main schools :
1. Soshu – located at Kamakura , known for itame hada and midareba hamon in nie deki.
2. Bizen – located at Okayama, known for mokume hada and midareba hamon in nioi deki
3. Yamashiro – located at Kyoto , known for mokume hada and suguha hamon in nei deki
4. Yamato – located near Nara, known for masame hada and suguha hamon in nie deki
5. Mino – Located at Gifu, known for hard mokume hada and midareba mixed with togari-ba

These schools are called the Gokaden or the five traditions. Bizen was the most active and most popular school during these times.

Sources:
The Connoisseur’s Book of Japanese Swords
The craft of the Japanese Sword
Wikipedia

Once the blade reached the 750-800°C, the structure of steel changes to austenite. Now, when the blade is quickly cooled by quenching (in water), austenite changes to martensite, the hardest type of steel. However, because of the clay application, the blade will cool more slowly where the clay is thick (on the back of the blade), turning not into martensite but instead forming ferrite and pearlite, which are softer and more flexible. So as result, you will get martensite on the edge and ferrite & pearlite on the back which gives the sword a ‘flexible construction’.

This hardening process also creates a visible change in the surface of the metal. It mainly depends on how the clay mixture was applied, but variety of effects can be produced and seen without looking ‘inside’ the blade. This pattern is called the hamon, and is one of the most important aspects in the aesthetic appearance of the Japanese sword. Like the jihada ( the surface pattern of the blade ), each of these hamon patterns has a specific name. Sugu, for example, is a very straight hamon, Gunome a zigzag pattern, Notare a wave pattern,etc.

Once the blade is successfully hardenend ( and in most cases, 50% or more of the blades are failing and does show cracks along the blade ) it’s not totally done. In most of the info your read, they talk about the forging, the hardening and that they continue with the polishing, mounting, etc but they all forget 1 important step, the tempering of the blade.

During the tempering process, the blade is heated again but this time to a much lower temperature and re-quenched. Since the temperature is far below the critical temperature (that is needed to harden the blade and change the structure of the steel), it won’t change the molecular structure of the steel anymore . Instead, it will simply help to relieve any internal stresses which the hardening process have built up.

The hardening process of the blade is in one of the most important and perhaps the most difficult part of the  sword making process. It is the correct hardening of the Japanese sword that gives the blade its ability to take and retain an amazing sharpness.

After the blade is forged and finished to it’s final (raw) shape, the differential hardening process can begin. To start with, the blade is being coated in a mixture (also know as yakibatsuch in Japanese ) of water, clay, ash, and other ingredients. Every smith has his own and in most cases, a ‘secret’ special recipe. The clay mixture is applied over the surface, thicker along the ‘mune’ (or spine) and thinner at the ‘ha’ (edge). In other words, the clay mixture will act as an insulating “blanket” during the quenching process. Allowing those areas that are covered by a thicker layer of clay to cool much more slowly.

Once this is done, “ashi” is applied to the clay coat. Ashi are the thin strips of clay you can see over the whole surface of the blade on this picture. These stripes are providing some insulating action in the quench as well, and will form little sections of softer material in the hardened edge. The Ashi are giving the blade the ability to prevent ‘cracks’ in the blade under hard use and lot of pressure. They also contribute to the formation of crystalline features within and around the hamon itself.