1. Select iron steel pieces and squeeze and pile them together in the forging process.
2. A wetted Japanese paper will be used to wrap the steel block. This prevents the steel layers from splitting over, collapsing or falling off. It was coated with rice straw ashes to prevent over heating and to compensate for the loss of carbon which occurred of heating.
3. Clay slurry was poured onto the block. Clay slurry and straw ashes help heat pass evenly from the block to the core.
4. According to the sword smith’s experience, the steel block would be taken out of the forge after it was boiled for a while, and then hammer and compact the block layers.
5. Then the block was put into forge and was hammered again.
6. Repeated several times, the steel block will become a piece of thick and flat steel.
7. The next stage is folding back. The steel was cut from the middle and was folded. After a dozen times of repeated folding, the impurities were squeezed off or scattered by the hammer blows. Each folding is coated with straw ashes and clay slurry. Then this steel was hammered to a U shape. This is the jacket of the blade.
8 . A slightly softer steel was inserted into the jacket to form the core of the blade. The jacket is hard and it is the edge of the blade. The core makes the blade more flexible inside to absorb the shock of the attack stroke. The jacket and core distinguish the blade from blades made elsewhere.
9. During hammering, the swordsmith had to make sure not destroy the balance of the jacket and the core steels. Then the steel was quenched by water and was hammered again. At this time, all impurities were beaten off the blade steel.
10. Next is the making of hamon. The swordsmith made hamon by special clay mixture. He painted the edge with a kind of thin clay mixture and painted the left of the blade with another kind of thick mixture. This helps the blade not be heated up too much and over harden. Then he designed the hamon on blade by clay mixture. When the mixture dried, the blade was fired again. After that the hamon was created.
11. Finally is hardening the edge. In this stage the clay coating was still on the blade and it was put into fire again. The swordsmith made the heat as even as possible. Then the blade was quenched suddenly in water. The edge became particularly hard. And then the blade was fired again and next it was tempered by quenching again. This made the strengths increase in the harden edge and insured the entire blade flexible and strong. After that the curvature of sword has increased slightly.