Forging the Blade
The raw material for this blade spent most of the last century on a former homestead.
A large portion of the steel was used for another blade, this was the piece cut from half of the left side.
Slowly drying the clay for yaki-ire over the embers in the charcoal forge.
After yaki-ire, an #80 grit Sun Tiger stone reveals the approximate hamon as the geometry is set.
Habaki forged to shape in preparation for silver soldering in the charcoal forge.
The habaki is textured with files and patinated using a blend of copper salts similar to rokusho.
A two part black buffalo horn (ura) and blond cow horn (omote) lock keeps the two halves aligned when joined.
The omote half contains the edge entirely and has an oil collecting reservoir at the tip.
The ura half does not contain the edge, keeping it entirely in the omote half.
Kataki Tsuka & Saya
The hardwood block is split and carved out to fit the ireko saya and the tang and then rejoined using sokui (rice paste glue). This wood is very hard on tools and they require frequent sharpening.
Nori-urushi, a mixture of natural urushi lacquer and sokui is used to reinforce certain areas, particularly the koiguchi where the wood is thinner.
Mixing the urushi and sokui along with a bit of extra water to help it cure inside the joint.
It can take at least a month to fully cure nori-urushi inside a wood joint, more time is better for strength.
After the nori-urushi is fully cured the tsuka and saya are shaped with kanna and smoothed with fine rasps and the horn mekugi peg is fitted.
An antler crown and tip are used to form a very organic kurikata (栗形, a cord loop) and obidome (帯留, “belt stop”), usually called kaerizuno (返角, “turn-back horn”).
The antler kurikata is fit to the saya using a carved sliding dovetail, with no room to spare!
The kurikata slides in from one side and then tightens as it reaches the final position.
The obidome has a tenon that fits into a mortise carved in the saya, again carved right to the ireko saya.
The obidome/kaerizuno will be attached with sokui after the saya is lacquered.
In preparation for lacquering, the open grain is cleared of dust using a stiff brush.
Ready for fukiurushi, the thin layer of wiped on urushi will preserve the interesting surface texture of the wood.
After the lacquer has cured the surface has become a rich, glossy dark chocolate colour.
Once all the parts are made and fitted the blade can be taken through the final polishing stages using Japanese waterstones. The natural #700 used to remove the last of the arato/kongo-do stone scratches.
Several stones later, hazuya and jizuya fingerstones made from flakes of uchigumori-do and narutaki-do koppa attached to washi paper with natural urushi are used to even the surface and add depth. This stage is very time consuming as is the uchigumori-do before it.
The fine surface grain of the steel brought out by the uchigumori stone throws multiple colours in sunlight.
A look at all the koshirae parts before assembly
Antler kurikata and obidome attached using sokui and tapped into place with a small mallet.
Inserting the ireko saya into the koshirae.
Completed aikuchi koshirae.
Furusato tanto forged from reclaimed antique steel.
View of the spine with peaked iori mune.
Macro detail of the interesting texture of the Tshikalakala wood pores.