How he forges
He forges six to eight hours a day, and a sword takes him about four weeks. He works with tatara tamahagane (玉鋼, tamahagane). The longest and hardest stage, he says, is the folding, the 折り返し鍛錬 (orikaeshi tanren), and he has a method of his own, an 奥義 (ōgi, “secret of the craft”), that he cannot teach; there are so many forging methods that a lifetime will not be enough for him.
The replica of the Hotarumaru
Without the original, he and Fukudome worked from documents and from an oshigata (押形, oshigata) kept at a crafts centre in Kumamoto. The hard part was erasing their own habits as swordsmiths and not knowing the thickness, the kasane (重ね, kasane), of the blade.
Other work
He also forges kitchen knives with the techniques of the sword, signed.
Gallery
Forging under the power hammer: the cover of the 2021 report. Oita Katete (オオイタカテテ, Ōita katete), web magazine of Ōita Prefecture · © Ōita Prefecture · source 
With one of the ōdachi of the replica of the Hotarumaru (蛍丸, Hotarumaru). Oita Katete (オオイタカテテ, Ōita katete), web magazine of Ōita Prefecture · © Ōita Prefecture · source 
Tamahagane (玉鋼, tamahagane), tatara steel. Oita Katete (オオイタカテテ, Ōita katete), web magazine of Ōita Prefecture · © Ōita Prefecture · source 
The stages of the forging, from raw steel to the blade. Oita Katete (オオイタカテテ, Ōita katete), web magazine of Ōita Prefecture · © Ōita Prefecture · source 
Under the power hammer. Oita Katete (オオイタカテテ, Ōita katete), web magazine of Ōita Prefecture · © Ōita Prefecture · source 
The folding of the steel. Oita Katete (オオイタカテテ, Ōita katete), web magazine of Ōita Prefecture · © Ōita Prefecture · source 
A ritual forging at night, before the public. Oita Katete (オオイタカテテ, Ōita katete), web magazine of Ōita Prefecture · © Ōita Prefecture · source 
Three kitchen knives forged with the techniques of the sword. Oita Katete (オオイタカテテ, Ōita katete), web magazine of Ōita Prefecture · © Ōita Prefecture · source 
The entrance of his forge, with the shimenawa (注連縄, shimenawa). Photo: dealer in Japan 
Forging in ceremonial dress, and two blades of his. Photo: dealer in Japan