The Honyaki, An Exceptional Knife
Author: Olivier Caza Berthelet
Reading time: 5 minutes
Japanese knives are famous for their exceptional sharpness and longevity, the result of sophisticated manufacturing techniques. The most common method is to create a "san-mai" knife, with a core of hard steel sandwiched between two layers of softer steel. This process, known as awase, enables the knife to retain an extremely sharp edge while being protected from impact. However, there is an older and rarer manufacturing method, called Honyaki, which embodies the very essence of Japanese craftsmanship.
What is Honyaki?
The term Honyaki (本焼) literally means "true fired" and refers to a traditional Japanese forging technique. Unlike awase knives, which are made by rolling several layers of steel, Honyaki knives are forged from a single piece of high-carbon steel. This process, similar to the manufacture of samurai swords (nihonto), involves applying clay to the blade before tempering to create a contrast between a hard edge and a softer back. The result is a knife of exceptional hardness, with a cutting edge that stays sharper longer.
Manufacturing process: between tradition and precision
Choice of materials and tempering
The manufacture of a Honyaki knife begins with the selection of the steel. Commonly used steels include Shirogami (white steel) and Aogami (blue steel), produced by Hitachi's Yasugi Specialty Steel. These steels are renowned for their ability to achieve high levels of hardness, thanks in particular to water quenching, a rapid cooling method that increases the steel's hardness while creating a visible quench line, the hamon. When honyaki is water-quenched, it's called "mizu honyaki".
Water quenching is particularly effective in achieving the highest possible level of sharpness. This method creates an extremely hard blade, but also makes the process more risky, as the blade can crack under heat stress.
The crucial role of the blacksmith
The manufacture of a Honyaki knife requires exceptional skills that only a limited number of renowned blacksmiths possess. An experienced blacksmith forges each blade with unrivalled precision, applying a special paste of water, charcoal and clay to create the ideal tempering conditions. The recipe and its proportions differ from one blacksmith to another, and often remain a well-kept secret.
Here are a few renowned Japanese blacksmiths who still produce Honyaki blades today: Kenji Togashi, Yoshikazu Tanaka and Satoshi Nakagawa. Visit our rare knives section to discover our selection.
Sharpening and finishing
Once the blade has been tempered, it is left to harden naturally before being sharpened and polished. The sharpening process is a delicate one, as the hardness of the blade makes it more difficult to sharpen than laminated knives.
Why choose a Honyaki knife?
Honyaki knives are not just kitchen tools; they are works of art. Their complex manufacture, combined with the difficulty of water tempering, explains why they are so rare and precious. Because of their exceptional hardness, these knives retain their sharpness longer than most other types of knife, but they require special care when sharpening and using.
What's more, the beauty of Honyaki knives lies in their simplicity and purity. Unlike laminated blades, where soft steel protects the hard core, Honyaki knives rely entirely on the smith's skill to balance hardness and resilience in a single piece of steel.
Conclusion
Honyaki represents the pinnacle of Japanese cutlery craftsmanship. Forged with exceptional expertise and meticulous attention to detail, these knives are both work tools of unrivalled precision and precious collector's items. Whether for a professional chef or a passionate collector, a Honyaki knife is much more than just an instrument: it's a piece of history, forged in the tradition and mastery of Japanese craftsmanship.
