Itten Forest Tanto

Itten (一転, “eat..ten”) means a turning point or turn of events, as in a story or set of circumstances. It carries the idea of a sudden or unexpected shift, return, or change, and often means a complete turn around, in skateboard terminology this is known as a one-eighty (180°). This is the first hammer-finished full sized forest tanto and the first satoyama tanto mounted in kura style.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

The core of this project is a charcoal-forged blade, water quenched with clay and sharpened with waterstones, an outdoor knife that has the foundation of the Japanese sword. The chisagatana mounting is in the rustic kura (蔵, storehouse) style and includes antique fittings from swords carried centuries ago.

Satoyama are the managed forest areas that border the cultivated fields and the mountain wilds in Japan. Historically they provided soil nutrients, firewood, edible plants, mushrooms, fish, and game, and supported many local industries and crafts such as farming, timber construction, and charcoal making. The interaction of forest, arable land, wetlands, and streams are an important component of the satoyama landscape.

The subtle appearance of hammer marks on the blade, the rustic carved and lacquered wooden mountings, paired with antique sword fittings—treasures from the kura storehouse. A hand crafted tool for adventure that would be very much at home in the field, forest, or mountain landscape.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Forged from an antique chisel that was forged from an older file decades ago, the blade profile of the forest style tanto is based on a classical yoroidoshi tanto and has a tapering shape with slight drop point. The temper of this high carbon steel blade has been left relatively hard, a particular combination of steel and heat treatment that is well suited to users who require a good edge and are willing to take care of it.

The tang is constructed in a similar manner to a Japanese sword requiring only a single bamboo peg to hold the knife assembly together. In addition to the sense of beautiful simplicity, this design allows the knife to be taken apart for cleaning, polishing, detailed cutting tasks, or major resharpening work.

Five antique Edo period sword fittings are incorporated into the mounting of this knife—the shakudo fuchi (ferrule, of copper and gold alloy) with carved brush-style horse, inlaid iron tsuba (hand guard), copper seppa (blade washers), and fine nanako-textured shakudo koiguchi (scabbard mouth). Additionally, the iron kashira (pommel) appears to have been a WWII field-repair and the brass habaki (blade collar) may have come from an iaido practitioner’s sword.

The kataki hardwood handle is carved from Sapele and finished with traditional fukiurushi lacquer built up in multiple coats to darken and deepen the look of the wood without losing the texture of the grain. The mekugi (removable peg) and kurikata (cord loop) are carved from buffalo horn. The scabbard is carved from Japanese hounoki (magnolia), left with subtle planed facets, and lacquered in a dark chocolate colour made from natural urushi, black urushi, and ground red crimson lake stone pigment.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

One of the crowning details of this tanto is the traditionally hand crafted shikagawa leather sageo made in Kumamoto Japan by Hans Koga in the classical Higo method used by craftsmen in the Edo period, beginning with thin buckskin, cutting, stretching, rolling, wet folding, onion dying, and hand stitching with fine silk thread along the back.

The blade is just under 10″ long with an overall length of just over 15″ and 17.25″ when sheathed. The spine at the munemachi is just over 6mm thick.

Specifications

長さ/刃長 Nagasa (blade length): 257mm
重ね/元重 Motokasane (spine thickness): 6mm
元幅 Motohaba (blade width): 30mm
反り Sori (spine curve): uchizori (slight reverse curve)
中心/茎 Nakago (tang length): 95mm
柄長 Tsuka (handle length): 115mm
拵全長 Koshirae (overall): 540mm

形 Katachi (geometry): hira-zukuri, mitsu-mune, with ubuha
刃文 Hamon (edge pattern): suguha
帽子/鋩子 Boshi (tip pattern): ko-maru
中心/茎 Nakago (tang): futsu, kuri-jiri, one mekugi-ana
銘 Mei (signature): mumei (unsigned)
拵 Koshirae (mounting): satoyama kura style chisagatana, issaku (sole authorship) plus 7 antique parts

Materials: antique file steel, Sapele, Hounoki, buffalo horn, antique fittings, natural urushi lacquer, crimson lake

This piece is in a private collection in Alabama.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.


Process

This blade was forged and yaki-ire performed at the museum forge. It began as an old chisel that was hand forged from an even older file decades or perhaps generations ago.

Island Blacksmith: Charcoal forged knives from reclaimed steel.
A chisel that was forged from an old file at an unknown date in history.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
Using the large two-handed mukozuchi sledge as a one-handed bench hammer for initial drawing out.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
The sunobe (blade pre-form) allocates the correct amount of steel to each area of the blade and establishes the tapers, note that the edge is facing upwards.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
The bevels forged in, note the light across the anvil to highlight any deep hammer marks while working.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
Only hammer work up to this point, the forged profile and bevels before filing in the final details.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
After filing the notches and profile the steel is normalized by thermal cycling to relieve stresses.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
The final profile, note the slight reverse curve on the spine to compensate for yaki-ire.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
Draw filing along the edge to prepare a smooth area for sharpening after hardening.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
Applying the clay for yaki-ire, it will delay the cooling effect and produce a hardened edge with a tough spine.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
After successfully surviving the stress of yaki-ire the steel has now become a blade.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
With some cleaning and a soak in hot vinegar water the hamon and hardened area can be seen in certain light.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
In direct light the tones of crimson lake can be seen in the layers of urushi on the faceted scabbard.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
All parts of the koshirae carefully fit and finished, prepared for final assembly.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
The kashira, koiguchi, and kurikata are attached using nikawa (膠, にかわ, natural hide glue).

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.
Fully assembled for the first time.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
Special delivery from Japan.
Island Blacksmith: Charcoal forged knives from reclaimed steel.
Hand crafted leather sageo made in Kumamoto, Japan by Hans Koga.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.

Island Blacksmith: Charcoal forged knives from reclaimed steel.