Posts Tagged ‘Watanabe Blade’

180mm Kuro-uchi Gyuto by Shinichi Watanabe

Published: October 27th, 2011 by The Edge Observer 6

Watanabe Blade is located in Sanjo City in the Niigata Prefecture of Japan.  The operator, Shinichi Watanabe is a sixth generation Japanese blade smith who hand forges a large range of kitchen, gardening and utility blades using traditional techniques. The 180mm Kuro-uchi Gyuto is one of Watanabe Blade’s biggest exports to the West due to it’s familiar profile, similar to that of typical Western kitchen knives.

180mm Watanabe Kurouchi Gyuto

The beginning of the name, Kuro-uchi, refers to the knife’s finish which is considered rustic. These knives have the bulk of the blade unpolished, still bearing the hammer marks and coloration from forging and tempering.  The “unfinished”  surface compliments the finished edge.  Kuro-uchi blades emphasize the ridge-line, or in Japanese terms Shinogi, creating a beautiful contrast that references both process and refinement.  Gyuto is a utility knife, the name roughly translating to cow knife.

The blade of the Gyuto is constructed using the Warikomi technique.  A type of cladding where a softer stainless outer layer is wrapped around 3 sides of a hard, high carbon steel core (sides and spine, with the edge exposed). The blade grind reveals the forge welded lamination which is visible through the typical wavy line of the hamon (the Japanese term for the line delineating two steels and/or a difference in temper).  The hamon is also obvious through the steel’s respective finish. The carbon steel has a finer grain and high polish in comparison to the toothier stainless, matte cladding.  The hamon on hand forged knives appears as an organic, unsymmetrical line and is considered an indicator of both the hand forging process and the blade’s quality.

Watanabe Gyuto forge tapered spine

The knife is forge tapered toward a very thin tip (kissaki).  Forge tapering adds considerable strength and flexibility while allowing the blade to be worked razor thin.  The repeated hammering of the steel densely packs the molecular structure which translates into a much finer edge than those found on machine automated products.  This differs from stamped or rolled blades because their process causes uneven compression of the metal and or tearing in the structure.

The Kuro-uchi Gyuto core is made from Yasuki blue steel which is a machine made Tamahagane by Hitachi metals.  Tamahagane are superior grade steels with a high carbon content.  Made from black iron sands, they are considered the only legitimate steel for traditional edges. The Yasuki Blue is treated to a high hardness of HRc 63-65.  This is much harder than typical western knives which normally have a HRc in the high fifties.  The outer layer is SUS410 stainless and finished with the maker’s signature.  Although the knife has a very high hardness, the composition of the steel allows the blade to be easily maintained without sacrificing edge retention.

Kurouchi Gyuto

The knife has a hidden tang with a rat tail profile and is set into chestnut wood that is burnt to create a dark patina.  The Kakumaki (ferulle or the collar around the handle where it meets the blade) is plastic.  For an additional charge this can be made from Buffalo horn.  The over all shape of the handle is very traditional.  It  flares slightly toward the pommel and is oblong in profile.  A slight ridge down the finger-side adds extra grip.  The result is very comfortable and easy to maintain.  Handles on Japanese cooking knives are made to be easily changed.  This allows for greater longevity.  Smaller handles can also be attached as the blade gets shrinks in profile from years of sharpening.  This is a practice that is not uncommon as the hand forged blades will often last a lifetime.

Burnt chesnut wood handle

As a result of the quality materials, Warikomi technique and hand forged process the Watanabe Kuro-uchi Gyuto will be able to achieve a flexibility, thinness and fine edge unmatched by kitchen knives produced in a typical manufacturing scenario.  From personal experience I have never handled a kitchen knife (any knife) this sharp.  The craftsmanship is not only beautiful, it retains a rich history and time proven design that is only available as a result of the knowledge passed from master blade-smith to apprentice.

Shinichi Watanabe forging a GyutoinspectiongrindingsigningA Finished Gyuto

Pros

Hand Forged (Forge Tapered, dense grain structure)
Warikomi technique makes it strong and easy to maintain
Easily replaceable handles
Very reasonably priced

Cons

You don’t own one yet.

Specs

Total Dimensions and weight:

Length 12″ (305mm)
weight 3.5 Oz (100g)

Blade

Blade Length 7.09″ 180 mm
Blade thickness varies approx .067″ average (1.7 mm)
Warikomi cladding
SUS410 shell
Yakuki blue steel core
Kuro-uchi finish

Handle

Burnt chesnut wood
Plastic kakumaki

Hand made in Japan

Find other Watanabe products at Watanabe Blade