The resulting blade is supposed to have the natural beauty of a waterfall (clear and pure) and the pattern along its edge (hamon) is likened to the mist or fog hanging in a remote valley.

History of the Japanese sword

 

The Japanese sword history is very mystical.  One of the most sacred treasures in Japan is a sword called Kusanagi-no-Tsurugi which was believed to be found inside a dragon’s tail. Together with a jewel and a mirror, this sword is considered a gift from the gods.

 

What is a Japanese sword?

 

Nihonto is usually the general term for the different types of Japanese swords and they may be classified according to length:

 

1. Japanese long sword (daito) – is more than 2 shaku (1 shaku = 11.93 inches) in length. Examples of this are the ancient long sword (tachi) and the Samurai katana. The long sword katana is also used in martial arts that teach Japanese sword fighting techniques and Japanese sword cutting technique. Beginners are trained using practice swords made of wood (bokken) and aluminum called Japanese Iaido swords (iaito).

 

2. medium sword (shoto) – has a length shorter than a katana but longer than a knife.  Examples of a medium sword are wakizashi and a kodachi.  A wakizashi is usually paired with the katana to comprise a daisho (short and long sword) of a Samurai warrior.  A kodachi had a greater curvature than a wakizashi and was traditionally worn by merchants.

 

3. tanto – is a Japanese dagger with a length less than 12 inches.  It would serve as an auxiliary weapon for a Samurai and would be used in ritual suicide (seppuku).  Women and tradesmen would also use this as protective weapon. 

 

Making the Japanese sword: A Spiritual Endeavor

 

Japanese sword making is regarded as a supreme form of artistic expression.  It is more of a spiritual undertaking than being merely a craft. It is believed that though the sword is made by man from natural resources, its completion is to be decided by the gods. Before starting the process of making a sword, the Japanese sword maker would start fasting and would have to undergo other purification rites.  He would wear white robes of a Shinto (native Japanese religion) priest and purifies his mind.  He then channels his spiritual, mental, and physical strength into forging the sword.

 

• The steel

The best quality of sword comes from the right kind of steel.  Traditional Japanese swords are made from black sand carbon steel (tamahagane) which gives the unique qualities of hardness and malleability to a Japanese sword.  This is produced through a smelting process using a traditional Japanese furnace (tatara).

 

Tons of charcoal and black sand are heated to make tamahagane and the whole process would usually take five days to be completed.

 

• Sorting the Steel

 
When the actual steel for the blade is formed, it will be hammered and broken into small pieces.  The pieces then are sorted according to their hardness. The harder pieces of steel are those with higher carbon while the softer ones contain lower carbon.

 

These pieces of steel will be heated separately but before that, they would be wrapped with dampened paper and a light covering of clay.  This is to regulate the amount of heat so the steel does not completely melt.  The wrapped pieces are placed inside a forge and heated up to 1300°C. 

 

• Folding

The steel are taken out from the forge.  They will be hammered into flat sheets and are folded (Orikaeshi tanren).  The process eliminates any remaining impurities that weaken the steel. Such impurities fly off as sparks when hammered. The harder steel is folded in no more than fifteen times while the softer steel is folded up to ten times.  At the end of the folding stage, a small block of steel is formed.

 

• Combining the steel

The pieces of steel with varying carbon content and hardness are then combined so that the blade will have a balanced quality of strength and flexibility.  Combination of steel may be done in various ways, three examples are:
o Placing a layer of soft metal between two layers of hard metal
o Forming the hard steel into a U-shape and inserting the softer metal in the hallow space of the “U”
o Placing a layer of soft steel on top of a layer of hard steel, then they are folded and hammered together

 

The harder metal will act as a jacket steel and becomes the cutting edge section of the blade.  The softer, more flexible metal will be the core steel which will serve as the back edge of the blade that will be resistant to shock when hit by another sword or metal.

 

• Forming the Japanese sword blade

The combined steel is now pounded with a large hammer to form the approximate shape of a blade. It is forged and shaped further using a small hammer to form the correct structure of the blade – shaping the spine or back edge, the sharp cutting edge, and the tip (kissaki).

 

• Clay coating, Heat-Tempering, and Quenching

Heat tempering is a process of heating the blade and quenching it in cold water immediately.  The rapid change in the temperature (from hot to cold) gives an extreme hardness and strength to the cutting edge of the blade.

 

Before putting the blade to the forge, it is coated with a mixture of clay and ash. Thicker coating will be applied on the back edge while a thinner coating is applied on the cutting edge.  This is to protect the back edge from the fast changing temperature that could harden the blade.

 

In the old times, the right amount of heat is determined when the blade’s color is likened to the color of the early morning sun.  When that is reached, the blade is taken out from the forge and quenched in cold water immediately.

 

Later in the process, a wavy pattern will appear on the sword.  This pattern is called hamon and is one of the factors that comprise an authentic Japanese sword.

 

• Japanese sword sharpening

Once the tempering process is finished, an expert sword smith does a preliminary Japanese sword sharpening to shape the basic details of the blade. It is also in this stage that Japanese sword markings like signatures and file markings are etched on the tang.

 

• Polishing

The Japanese sword blade is then sent to a master in polishing swords. The perfection of the blade in terms of artistic, aesthetic, and spiritual value relies on his skill. When the blade is finally done, it will be sent to another craftsman to assemble the entire sword and install the other Japanese sword parts including the handle, hand guard, fittings, and the scabbard.

 

Now you know how complex is the process of making a sword to achieve superb quality and beauty.  That is why nowadays, it can be hard to find real Japanese sword that went through traditional forging and such a sword is expensive.  Nevertheless, if you are a serious collector, you know it is all worth it.