How the Katana Sword is Made
The Katana is one of the most famous swords in history, not only for its cutting ability but also for its unique ability to be drawn and struck with a single movement. This is due to its semi-curved structure that is able to adapt to the warrior’s body movements. This attribute has influenced several martial arts that focus on the katana and is one of the reasons why the sword is so revered.
The first step in the creation of a katana is to heat the clay coated tamahagane in a furnace to a red-hot state. Once heated the smith will then plunge the blade into a pool of cold quenching liquid such as water or oil. Through this process of differential tempering the hardness of the steel is differentiated between the edge and the spine. This creates a visual wave like pattern known as the Hamon, a sign of a well made sword.
The next step is to remove any slag from the tamahagane and hammer it into a U-shaped channel. Here he will then place the harder, high carbon steel into the channel and forge it together using a technique called Kobuse Kitae. This creates the strong and deadly katana blade that the Samurai admired so much. The hard steel will form the outer shell and deadly blade while the soft lower section will provide a resilient core that can be cut with the wrist by using the technique of shikari (whacking). Once forged, the smith will then grind down any sharp edges on the sword. The smith will also check the nakago (blade throat) for small scratches and do a rough grinding. He will then polish the blade with a series of progressively finer stones. This will bring out the beauty of the hamon and the grain of the folded steel, making the blade both durable and razor sharp. click on this page