Making the Icho Hime Kotanto
Hand forged harrow tooth steel, copper habaki, Nootka Cypress and Ebony tsuka with ray skin wrap, Purpleheart saya, brush-finished silver fuchi by Nina of
This long, sleek piece is a collaboration and is named for the ginko leaf design on the custom silver fuchi made by Nina. The ginko leaf opening was cut by hand with a jeweler’s saw and layered over a background of patinated silver. The ray skin handle wrap is attached with kusune (薬練, くすね, natural pine resin glue made from matsuyani).
The clay tempered blade blade construction is muku with a hira-zukuri shape. This blade has an interesting hamon with a mizukage, a lot of surface activity, and visible particles. The habaki is hand forged from a scrap copper bar and the handle is carved from Nootka Cypress and wrapped with black ray skin. The Purpleheart scabbard has been coated with pure tung oil. The final work may be seen here:
The hand forged and clay tempered blade is left in rough polish during the mounting process to protect the final finish from scratches while working.
A strip of copper is cut with a chisel, softened by annealing, and cold forged into a tapered profile along the short axis.
The copper strip is forged around the blade and carefully fit to the taper of the tang.
A notch has been cut to rest against the the mune machi and the excess copper is trimmed off the sides and bottom.
The tiny compound wedge called machigane is made to fill the gap between the lower edge, the hamachi, and the nakago no ha (bottom edge of the tang). The habaki will be made just slightly under size and hammered out to fit in place.
Steel wire provides pressure while the machigane is soldered into place with silver solder. The excess is cut off, and then the habaki is cold hammer fit, filed to shape, and given a rough polish.
A piece of copper water pipe is annealed, split, and hammered flat, then chiseled and filed to precisely fit over the tang behind the habaki.
The newly formed copper sheet will be cut into an oval shape to match the fuchi, it will serve as a spacer or washer against the habaki.
Meanwhile, Nina has been hard at work creating a silver fuchi in her signature style, hand sawn and formed.
The copper tenjo-gane is soldered into the silver band.
The ginko leaf is heat patinated and the upper surface is given a brushed finish.
A piece of Nootka Cypress is sawn in two and carved to receive the tang. Once the fit is right, it is glued with sokui (rice paste glue) and bound tightly to dry.
When Nina’s piece arrives, the front of the handle is carved to fit inside the silver fuchi.
A hole is drilled for the mekugi and the rest of the handle is shaped to match the inside profile of the fuchi.
The pommel end of the handle is keyed to hold a kashira carved from a scrap of Ebony and locked in with kusune (Pine resin glue).
An exact pattern of the tapered handle surface is fashioned from paper and then transferred with soapstone to the ray skin.
Hot kusune (Pine resin glue) is spread over the surface of the Nootka Cypress handle, then reheated a small section at a time.
Carefully heating and gluing a small strip at a time, the samegawa is wrapped and fastened smoothly to the handle.
I have had this scrap of Purpleheart for almost twenty years. Hand sawn in two in preparation for carving.
Pink sawdust! The halves are sanded flat on a stone quarried on Shiraishijima.
It ain’t pretty it just looks that way. Purpleheart: awesome colour, hard to work with.
Some judicious reduction, a bit of heat and some tung oil to bring out the natural colour.
A final polish for the blade and this kotanto will be ready for final assembly and a naming ceremony.
The habaki is given its final polish.
The assembled tsuka showing how the dark materials contrast with the silver.
A small but important part, the mekugi (peg) holds the whole knife together. In this case carved from a scrap of a scrap of Ebony.
The assembled tsuka koshirae (furniture) ready for assembly.
Time to review, here are the raw materials, check out the finished work below.
View the finished work