Since ancient times, iron forging
has prospered in Western Honshū thanks to the high-quality iron-sand available
there. Today, in a region formerly known as Inaba,
there are still blacksmiths using long-established traditional techniques.
The mountains of Chizu
indispensable for forging iron, is abundantly available in the mountains of
Tottori Prefecture. Forestry in this region also utilized iron tools, so the blacksmiths’ work was
closely entwined with local people’s daily lives.
Ōtsuka knife forging
Ōtsuka knife forgingThe Ōtsuka Knife Workshop is located
in a residential area. Here third-generation blacksmith, Yoshifumi Ōtsuka,
continues to make knives.
In the past many smithies could be seen around
Tottori Prefecture but now only two, including Mr. Ōtsuka’s, remain.
The forging process
The construction of a knife
blade is made from two materials: steel and ferrite. Sandwiching hard steel
between soft ferrite ensures a knife that is tough yet soft.
The steel and ferrite are softened
by heating on a coal fire, and then beaten flat using a mechanical electric
hammer to make them easily workable.
is used to cut a deep groove in a piece of ferrite; a pre-shaped piece of steel
is slotted into this groove. Iron sand is used to adhere the two metals.
The combined piece is heated and lengthened
into a knife form by beating with a hammer. The welding process hones the cutting edge
and the spine to a degree invisible to the eye. Beating the metal reduces the size of the
particles, which enhances the toughness of the knife.
The beaten metal is cut to the
desired knife shape using a template. Then the handle is made.
In order to harden the steel, the knife is
placed into water after it has been heated to 800℃ to rapidly cool it down to 250℃. This vital heat
treatment will determine how well the knife can cut.
Straightening and tempering
Immediately after the quenching is
complete, the knife is left in 100℃ water, before it
then gets pounded to straighten the surface using a hammer.
Next, the straightened knife in its hard
and brittle state is left in oil heated to 180℃. After that it is slightly heated once more to give the steel
the sharpening process. Various grinders are used to gradually finish the
Introducing Ōtsuka knives
Ōtsuka’s knives are made with
meticulous attention to detail so they are easy to hold, make the right sound
when cutting food, and even produce a nice texture of cut.
These knives can be enjoyed using
all five senses.
The all-purpose knife
Knives are made according to the
type of ingredients they are intended for – meat, fish or vegetables. The
all-purpose knife is made to incorporate the advantages of various different
knives to suit a wide range of purposes. It is frequently used in the home.
The vegetable knife
This knife, featuring a rectangular,
straight-edged blade, is most common in the Kantō region. It is ideal for fine cutting
or chopping of food, so ideal for preparing vegetables.
The Yamame knife
This small knife with a sharp point
is designed for cutting and trimming small river fish. The handle is made from a
cherry branch, which gives it durability and a rustic beauty. Users enjoy
seeing the knife change over the years.
The Yamagoya knife
This knife can be used to cut wild
boar meat or venison. It is popular with outdoor enthusiasts.
This type of knife has a very sharp tip and is used
to kill fish to preserve it fresh. Being made from steel sandwiched between two
stainless steel sides, this type of knife is resistant to rust.
The Fisherman’s knife
This is a multi-purpose knife made
for fishermen to use onboard a boat. Also known as a ‘sea knife’ it can be used
to cut and trim fish, for example to prepare sashimi.
Mr. Ōtsuka has a high reputation for
his outstanding skills and adherence to traditional techniques. He continues to
preserve these traditions, whilst also experimenting with new products and
recently it was difficult to get hold of Mr. Ōtsuka’s knives, but in the last
few years he started selling them at the local deluxe-shop COCOROSTORE, increasing
awareness and interest.