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 ?

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

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.