Once the habaki is made, it is time to consider the handle mounting furniture to complement the blade. Depending on the final vision, this may include several metal parts such as tsuba (hand guard), fuchi (ferrule), kashira (pommel), and one or more seppa (washers or spacers). In addition, the wood core of the tsuka (handle) may be wrapped in layers of rawhide and leather or silk cord. While the main purpose is functionality, the style of each of these components may range from austere to decorative and each should harmonize with the overall work.
Fittings may be made from steel, iron, silver, copper, or one of its alloys. A combination of forging, chiseling, soldering, filing, and polishing or hammer planishing is used for each component and then patina is applied to the final surface. Antique fittings may also be carefully restored, modified, and reused. Once the fittings are prepared, the blade is ready for a Tsuka (handle) and Saya (scabbard).
Seppa are used as spacers or washers between components of the koshirae. Most often next to the habaki, but also on the other side of the tsuba. The basic construction is simply a flat sheet of copper, silver, or an alloy, an opening slightly larger than the tang, and is shaped to match the finished fuchi and saya outline. They may be thin or thick, and can have fileworked or chiseled rims. The final fit to the tang is achieved by using a punch to push out four lobes of metal in the four corners and then filing to adjust slightly.
Tsuba for tanto are usually either non-existant or are relatively small. This leaves little room for embellishment so the focus is often on the rim, the profile, or the material itself. They can be made from either ferrous or non-ferrous metals, but generally have seki-gane (non-ferrous spacers) to keep them from contact with the tang if they are made from iron or steel.
The blank is forged to shape roughly and then the nakago-ana opened with a punch of appropriate profile, then filed and finished using traditional fire-texturing, patinating, and stabilizing techniques.
The fuchi is an important part of the strength and integrity of the tsuka. Encircling the front of the handle where the stress from the tang is greatest, it helps prevent the wood core from splitting. The most common method of fabricating the sleeve is a soldered loop with a small reinforcement over the joint at the mune. Another method, usually in iron, is to forge a solid loop by punching or forge welding. The tenjo-gane is most often copper and is usually fit in snugly and soldered from the inside or, in the case of iron Higo style fittings, a copper tenjo gane is forged in physically rather than soldered to the sleeve.
The kashira contributes somewhat to balance and protects the end of the handle from damage. In larger swords it also serves to contain the wood core of the tsuka against splitting from the back. It is often made of iron or a non-ferrous alloy and may be tied into the handle wrapping or attached with nikawa (膠, にかわ, natural hide glue) alone. Tanto and wakizashi often have kashira made of horn, they should be attached with nikawa and either tied with the ito or reinforced by a horn tenon into the tsuka.
Restoring Antique Fittings
Working with antique fittings is both a responsibility and a joy. There are a limited number of antiques in the world and they should be used with respect to the craftsmen and tradition they represent. At the same time there are many lost and orphaned parts that can be made beautiful again by restoration and use in appropriate projects.
Restoration should be undertaken very carefully and gently, preserving as much of the original patina as possible and avoiding use of any harsh chemicals. Traditional tools and techniques include antler tips to remove loose rust without damaging patina, a clay mixture for inducing patina, boiling in tea for stabilization, cotton cloth for polishing, and ibota wax for protection.
Although tanto have more variations than most other swords, there are generally two components to wrapping a handle, the first being the shikagawa (rawhide) or samegawa (ray skin) layer which adds incredible stiffness and resilience to the tsuka, and the second an optional leather or cord wrapping to add padding, grip, and compression to the tsuka. When possible, the shikagawa or samegawa may even fit part way under the fuchi for extra strength and integrity, but in most cases stops at the edge of the fuchi. Samegawa may be left raw or lacquered for water resistance. The ito wrapping is often silk cord or leather.
As the parts are finished, they are polished, cleaned, given a patina, and coated with ibota wax or tung oil to stabilize and protect their surfaces. The blade is given its final polish and then the tanto is ready for final assembly.