Custom HAP-40 Bunka Black 190mm (7.5) – SharpEdge

June 17,2024

Custom HAP-40 Bunka Black 190mm (7.5") is a multi-purpose knife which we designed in collaboration with the Yoshida Hamono Smithy. It's forged out of extremely hard HAP-40 steel (68 HRC). It features a custom maple burl Japanese handle in four colors: Kyoto Sunset, Okinawa Reef, Tokyo Night and Tottori Sand..
HAP-40 Bunka Black 190mm (7.5") is a multi-purpose knife from our HAP-40 series, which we designed in collaboration with the Yoshida Hamono smithy.BLADE SHAPE:With its typical functionality, Bunka design is intended for versatile use in Western cuisine. It has a flexible profile that is wide enough at the handle, a gently designed belly of the blade suitable for making either long or short cuts, a flat back side of the blade, and a thin tip for precise work with food.HANDLE:We chose a universal, octagonal shape that comfortably fits the hands of both right- and left-hand users. It offers a firm grip for easy and comfortable use.Handles are made of natural maple wood, which undergoes a special procedure of stabilization with resin. This ensures a long service life of the handle. During this process of stabilization, a color pigment is added which penetrates the wood in different ways, creating unique patterns. This makes every handle one-of-a-kind.Color and patterns of handles may vary from what is seen in the pictures. If you like a particular color hue, please contact us before placing an order.STEEL:The secret of this knife lies in its hard core made of a somewhat exotic Hitachi’s HAP-40 steel, that fits into the category of modern and technologically advanced steels. HAP-40 is fine-grained enough to sharpen very well, and knives made from it keep their sharpness 3-5 times longer than traditional knives. An interesting fact is that, considering it is a powder steel, it has an extremely small content of chromium (around 4%) and can react as a high-carbon steel in specific circumstances.This steel is heat-treated to an incredible 68 HRC, yet it can still be relatively easily sharpened on whetstones. It is extremely tough, and so not as likely to chip along the edge as the steel used in traditional knives.LAMINATION:Osamu-san chose a warikomi (also called “split and insert”) method. A glowing hot piece of iron is split and a piece of steel is inserted. This combination is then forged into one piece composed of a very hard steel core in a jacket of two external layers of softer, stainless steel. This creates a highly durable kitchen knife with a slightly more pliable blade. The main advantage of these knives is that they are thin, sharp and retain their edge very well.GEOMETRY:It has a double bevel (symmetrical) blade.BLADE FINISH:The blade has a dark finish, which is the reason this look is called kuro-uchi - the word “kuro” means black. This look is traditional and robust, with an unprocessed top part of the blade that has already developed a dark patina.ABOUT THE BLACKSMITH:The knife is manufactured at the smithy of Yoshida Hamono in Japan, a family company with an age-long tradition in manufacturing state-of-the-art tools and Japanese swords, i.e., katanas, by hand. Yoshida Hamono has a great deal of experience forging ZDP-189 steel in the traditional manner..

HAP-40 Bunka Black 190mm (7.5) is a multi-purpose knife from our HAP-40 series, which we designed in collaboration with the Yoshida Hamono smithy.

BLADE SHAPE:
With its typical functionality, Bunka design is intended for versatile use in Western cuisine. It has a flexible profile that is wide enough at the handle, a gently designed belly of the blade suitable for making either long or short cuts, a flat back side of the blade, and a thin tip for precise work with food.

HANDLE:
We chose a universal, octagonal shape that comfortably fits the hands of both right- and left-hand users. It offers a firm grip for easy and comfortable use.

Handles are made of natural maple wood, which undergoes a special procedure of stabilization with resin. This ensures a long service life of the handle. During this process of stabilization, a color pigment is added which penetrates the wood in different ways, creating unique patterns. This makes every handle one-of-a-kind.

Color and patterns of handles may vary from what is seen in the pictures. If you like a particular color hue, please contact us before placing an order.

STEEL:
The secret of this knife lies in its hard core made of a somewhat exotic Hitachi’s HAP-40 steel, that fits into the category of modern and technologically advanced steels. HAP-40 is fine-grained enough to sharpen very well, and knives made from it keep their sharpness 3-5 times longer than traditional knives. An interesting fact is that, considering it is a powder steel, it has an extremely small content of chromium (around 4%) and can react as a high-carbon steel in specific circumstances.

This steel is heat-treated to an incredible 68 HRC, yet it can still be relatively easily sharpened on whetstones. It is extremely tough, and so not as likely to chip along the edge as the steel used in traditional knives.

LAMINATION:
Osamu-san chose a warikomi (also called “split and insert”) method. A glowing hot piece of iron is split and a piece of steel is inserted. This combination is then forged into one piece composed of a very hard steel core in a jacket of two external layers of softer, stainless steel. This creates a highly durable kitchen knife with a slightly more pliable blade. The main advantage of these knives is that they are thin, sharp and retain their edge very well.

GEOMETRY:
It has a double bevel (symmetrical) blade.

BLADE FINISH:
The blade has a dark finish, which is the reason this look is called kuro-uchi - the word “kuro” means black. This look is traditional and robust, with an unprocessed top part of the blade that has already developed a dark patina.

ABOUT THE BLACKSMITH:
The knife is manufactured at the smithy of Yoshida Hamono in Japan, a family company with an age-long tradition in manufacturing state-of-the-art tools and Japanese swords, i.e., katanas, by hand. Yoshida Hamono has a great deal of experience forging ZDP-189 steel in the traditional manner.

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HAP-40 Bunka Black 190mm (7.5) is a multi-purpose knife from our HAP-40 series, which we designed in collaboration with the Yoshida Hamono smithy. BLADE SHAPE:With its typical functionality, Bunka design is intended for versatile use in Western cuisine. It has a flexible profile that is wide enough at the handle, a gently designed belly of the blade suitable for making either long or short cuts, a flat back side of the blade, and a thin tip for precise work with food. HANDLE:We chose a universal, octagonal shape that comfortably fits the hands of both right- and left-hand users. It offers a firm grip for easy and comfortable use. Handles are made of natural maple wood, which undergoes a special procedure of stabilization with resin. This ensures a long service life of the handle. During this process of stabilization, a color pigment is added which penetrates the wood in different ways, creating unique patterns. This makes every handle one-of-a-kind. Color and patterns of handles may vary from what is seen in the pictures. If you like a particular color hue, please contact us before placing an order. STEEL:The secret of this knife lies in its hard core made of a somewhat exotic Hitachi’s HAP-40 steel, that fits into the category of modern and technologically advanced steels. HAP-40 is fine-grained enough to sharpen very well, and knives made from it keep their sharpness 3-5 times longer than traditional knives. An interesting fact is that, considering it is a powder steel, it has an extremely small content of chromium (around 4%) and can react as a high-carbon steel in specific circumstances. This steel is heat-treated to an incredible 68 HRC, yet it can still be relatively easily sharpened on whetstones. It is extremely tough, and so not as likely to chip along the edge as the steel used in traditional knives. LAMINATION:Osamu-san chose a warikomi (also called “split and insert”) method. A glowing hot piece of iron is split and a piece of steel is inserted. This combination is then forged into one piece composed of a very hard steel core in a jacket of two external layers of softer, stainless steel. This creates a highly durable kitchen knife with a slightly more pliable blade. The main advantage of these knives is that they are thin, sharp and retain their edge very well. GEOMETRY:It has a double bevel (symmetrical) blade. BLADE FINISH:The blade has a dark finish, which is the reason this look is called kuro-uchi - the word “kuro” means black. This look is traditional and robust, with an unprocessed top part of the blade that has already developed a dark patina. ABOUT THE BLACKSMITH:The knife is manufactured at the smithy of Yoshida Hamono in Japan, a family company with an age-long tradition in manufacturing state-of-the-art tools and Japanese swords, i.e., katanas, by hand. Yoshida Hamono has a great deal of experience forging ZDP-189 steel in the traditional manner.