1) The steel is smelted in the traditional Tatara furnace creating a 'Kera' or bloom of raw steel. This bloom is broken into pieces by hammering and the pieces are separated visually by an accomplished smith, who can determine carbon content of each piece by its appearance.
2) Pieces of high carbon steel are selected for forming a billet of skin (outer layer) steel while pieces of lower carbon steel are selected for forming a core (inner layer) steel billet. The high carbon skin steel, when differentially quenched, will form a very hard edge while the lower carbon core steel will be softer, providing resilience to the blade and supporting the hard edge.
3) The pieces of high- and low-carbon steel are flattened and formed into separate stacks, ready for forming into billets.
4) Each stack is then covered in burnt straw; which aids in the forging process, and then forged into individual high- and lower- carbon billets.
5) The outer skin steel is folded multiple times to remove slag inclusions and voids. The repeated folding produces a fine Hada (grain pattern) when the blade is finally polished.
6) The folded skin steel is then wrapped around the softer core steel billet and forged into a blade. The blade is then ready to be differentially quenched, using the traditional clay method, polished, and mounted.
Today Paul Chen’s son Ron is following in his father’s footsteps and becoming very much a part of the Hanwei story. Ron, who has studied under Japanese legend Yoshindo Yoshihara, is the driving force behind Hanwei’s Tamahagane and Bainite blade development. Ron’s own blades illustrate his deep appreciation for the art of the Japanese sword and are sure to become collector pieces.