Japanese sword mountings

Japanese sword mountings are the various housings and associated fittings (tosogu) that hold the blade of a Japanese sword when it is being worn or stored. Koshirae (拵え) refers to the ornate mountings of a Japanese sword (e.g. katana), koshirae are used when the sword blade is being worn by its owner, whereas the shirasaya is a plain undecorated wooden mounting composed of a saya and tsuka that the sword blade is stored in when not being used.

Components

 * Fuchi (縁):The fuchi is a hilt collar between the tsuka and the tsuba.
 * Habaki (鎺):The habaki is a wedge shaped metal collar used to keep the sword from falling out of the saya and to support the fittings below; fitted at the ha-machi and mune-machi which precede the nakago.
 * Kaeshizuno (返し角) - a hook shaped fitting used to lock the saya to the obi while drawing.
 * Kashira (頭):The kashira is a butt cap (or pommel) on the end of the tsuka.
 * Kōgai (笄):The kōgai is a spike for hair arranging carried sometimes as part of Katana-Koshirae in another pocket.
 * Koiguchi (鯉口):The koiguchi is the mouth of the saya or its fitting; traditionally made of buffalo horn.
 * Kojiri (鐺):The kojiri is the end of the saya or the protective fitting at the end of the saya; also traditionally made of buffalo horn.
 * Kozuka (小柄):The kozuka is a decorative handle fitting for the kogatana; a small utility knife fit into a pocket on the saya.
 * Kuri-kata (栗形):The kuri-kata is a knob on the side of the saya for attaching the sageo.
 * Mekugi (目釘):The mekugi is a small peg for securing the tsuka to the nakago.
 * Menuki (目貫):The menuki are ornaments on the tsuka (generally under the tsuka-ito); to fit into the palm for grip and originally meant to hide the mekugi.
 * Mekugi-ana (茎穴):The mekugi-ana are the holes in the tsuka and nakago for the mekugi.
 * Sageo (下げ緒):The sageo is the cord used to tie saya to the belt/obi when worn.
 * Same-hada (鮫肌) - literally the pattern of the ray skin.
 * Same-kawa (samegawa) (鮫皮):same-kawa is the ray or shark skin wrapping of the tsuka  (handle/hilt).
 * Saya (鞘):The saya is a wooden scabbard for the blade; traditionally done in lacquered wood.
 * Seppa (切羽):The seppa are washers above and below the tsuba to tighten the fittings.
 * Shitodome (鵐目) - an accent on the kurikata for aesthetic purposes; often done in gold-ish metal in modern reproductions.
 * Tsuba (鍔 or 鐔):The tsuba is a hand guard.
 * Tsuka (柄):The tsuka is the hilt or handle; made of wood and wrapped in samegawa.
 * Tsuka-maki (柄巻) - the art of wrapping the tsuka, including the most common hineri maki and katate maki (battle wrap).
 * Tsuka-ito (柄糸):Tsuka-ito the wrap of the tsuka, traditionally silk but today most often in cotton and sometimes leather.
 * Wari-bashi (割箸) - metal chop-sticks fit in a pocket on the saya.

Shirasaya
A shirasaya (白鞘), literally "white scabbard", is a plain wooden Japanese blade mount consisting of a saya (scabbard) and tsuka (hilt), traditional made of nurizaya wood and used when a blade was not expected to see use for some time and needed to be stored. They were externally featureless save for the needed mekugi-ana to secure the nakago (tang), though sometimes sayagaki (blade information) was also present. The need for specialized storage is because prolonged koshirae mounting harmed the blade, owing to factors such as the lacquered wood retaining moisture and encouraging corrosion.

Such mountings are not intended for actual combat, as the lack of a tsuba (guard) and proper handle wrappings were deleterious; as such they would likely never make their way onto a battlefield. However, there have been loosely similar "hidden" mountings, such as the shikomizue. Also, many blades dating back to earlier Japanese history are today sold in such a format, along with modern-day reproductions; while most are purely decorative replicas, a few have functional blades.

Koshirae
The word koshirae is derived from the verb koshiraeru (拵える), which is no longer used in current speech. More commonly "tsukuru" is used in its place with both words meaning to "make, create, manufacture." A more accurate word is tōsō (刀装), meaning sword-furniture, where tōsōgu (刀装具) are the parts of the mounting in general, and "kanagu" stands for those made of metal. Gaisō (外装) are the "outer" mountings, as opposed to tōshin (刀身), the "body" of the sword.

A koshirae should be presented with the tsuka (hilt) to the left, particularly in times of peace with the reason being that you cannot unsheathe the sword easily this way. During the Edo period, many formalized rules were put into place: in times of war the tsuka should be presented to the right allowing the sword to be readily unsheathed.

Koshirae were meant not only for functional but also for aesthetic purposes, often using a family mon (crest) for identification.

Types of koshirae
The tachi style koshirae is the primary style of mounting used for the tachi, where the sword is suspended edge-down from two hangers (ashi) attached to the obi. The hilt (tsuka) often had a slightly stronger curvature than the blade, continuing the classic tachi increase in curvature as you go from the tip to the hilt. The hilt was usually secured with two pegs (mekugi), as compared to one peg for shorter blades including uchigatana and katana. The tachi style koshirae preceded the uchigatana (katana) style koshirae. The uchigatana style koshirae is the most commonly known koshirae and it is what most people associate with a samurai sword. Swords mounted in this style of koshirae are worn with the cutting edge up as opposed to the tachi style koshirae were the sword is worn with the cutting edge down. The han-dachi koshirae was worn katana style but included some tachi related fittings such as a kabuto-gane instead of a kashira. The aikuchi (匕首) (literally "fitting mouth") is a form of mounting for small Japanese swords in which the handle and the scabbard meet without a guard (tsuba) in between. Originally used on the koshigatana (a precursor to the wakizashi) to facilitate close wearing with armor, it became a fashionable upper-class mounting style for tantō (daggers) from the Kamakura period onwards.
 * Tachi
 * Uchigatana (katana)
 * Han-dachi (half tachi)
 * Aikuchi

According to S. Alexander Takeuchi from University of North Alabama, Department of Sociology, aikuchi, is a form of koshirae (mounting style) which commonly was used in tantō creation. The nomenclature of the word "aikuchi" is the following: the ai is a gerund which means meeting and kuchi is a noun that means mouth. The same formula is used in koi-guchi. So, aikuchi initially was a style of mounting in which the fuchi meets with the koi-guchi. The shikomizue (仕込み杖) or 'jotō' (杖刀 literally "staff sword") is a Japanese swordstick. It is most famous for its use by the fictional swordmaster Zatoichi. The name shikomi-zue is actually the name of a type of mounting; the sword blade was placed in a cane-like mounting (tsue), to conceal the fact that it was a sword. These mountings are not to be confused with the Shirasaya mountings, which were just plain wooden mountings with no decorations.
 * Shikomizue

Some shikomi-zue also concealed metsubushi, chains, hooks, and many other things. The shikomi-zue could be carried in public without arousing suspicion, making them perfect tools for shinobi. The aikuchi tantō known as kaiken is a small 8-10 inch long, single or double bladed dagger without ornamental fittings housed in a plain mount, formerly carried by men and women of the samurai class in Japan. It was useful for self-defense indoors where the long katana and intermediate wakizashi were inconvenient. Women carried them in their kimono either in a pocket like fold (futukoro) or in the sleeve (tamoto). for self-defense for suicide by means of slashing the veins in the left side of the neck (carotid artery).
 * Kaiken

Saya
Saya (鞘) is the Japanese term for a scabbard, and specifically refers to the scabbard for a sword or knife. The saya of a koshirae are normally manufactured from very lightweight wood, with a coat of lacquer on the exterior. The wood is light enough that great care must be taken when drawing the sword; incorrect form may result in the blade of the sword slicing through the saya and severing one or more fingers. Correct drawing and sheathing of the blade involves contacting the mune rather than ha to the inside of the saya. The saya also has a wooden knob (栗形) on one side for attaching a braided cord (sageo), and may have a shitodome to accent the kurigata as well as a butt cap (小尻) made from metal. Traditionally the koiguchi and kojiri were made from buffalo horn.

Parts of the saya
A sageo (下緒 or 下げ緒) is a hanging cord made of silk, cotton or leather that is passed through the hole in the kurigata (栗形) of a Japanese sword's saya. There are a number of different methods for wrapping and tying the sageo on the saya for display purposes. In some schools of Iaidō, the sageo is tied to the hakama when practicing.
 * Sageo

Tsuka
The tsuka is the hilt or handle of a Japanese sword.

Parts of the tsuka
The menuki are ornaments on the tsuka (generally under the tsuka-ito); to fit into the palm for grip.
 * Menuki

Tsuba
The tsuba (鍔) is usually a round or occasionally squarish guard at the end of the grip of bladed Japanese weapons, like the katana and its various declinations, tachi, wakizashi, tantō, naginata etc. They contribute to the balance of the weapon and to the protection of the hand. The tsuba was mostly meant to be used to prevent the hand from sliding onto the blade during thrusts as opposed to protecting from an opponent's blade. The chudan no kamae guard is determined by the tsuba and the curvature of the blade. The diameter of the average katana tsuba is 7.5 –, wakizashi tsuba is 6.2 –, and tantō tsuba is 4.5 –.

During the Muromachi period (1333–1573) and the Momoyama period (1573–1603) Tsuba were more for functionality than for decoration, being made of stronger metals and designs. During the Edo period (1603–1868) there was peace in Japan so tsuba became more ornamental and made of less practical metals such as gold.

Tsuba are usually finely decorated, and nowadays are collectors' items. Tsuba were made by whole dynasties of craftsmen whose only craft was making tsuba. They were usually lavishly decorated. In addition to being collectors items, they were often used as heirlooms, passed from one generation to the next. Japanese families with samurai roots sometimes have their family crest (mon) crafted onto a tsuba. Tsuba can be found in a variety of metals and alloys, including iron, steel, brass, copper and shakudo. In a duel, two participants may lock their katana together at the point of the tsuba and push, trying to gain a better position from which to strike the other down. This is known as tsubazeriai (鍔迫り合い), lit. pushing tsuba against each other. Tsubazeriai is a common sight in modern kendo.

In modern Japanese, tsubazeriai (鍔迫り合い) has also come to mean "to be in fierce competition."

Seppa
The seppa are washers used in front and behind the tsuba to tighten the fittings, seppa can be ornate or plain.

Habaki
The habaki (啖呵) is a piece of metal encircling the base of the blade of a Japanese bladed weapon. It has the double purpose of locking the tsuba (guard) in place, and to maintain the weapon in its saya (scabbard).

A katana, a type of Japanese longsword, is drawn by grasping the saya near the top and pressing the tsuba with the thumb to emerge the blade just enough to unwedge the habaki from inside the saya in a process called "koiguchi-no-kirikata". The blade is then free in the saya, and can be drawn out very quickly. This is known as "Koiguchi-o kiru", nukitsuke, or "tanka o kiru" (啖呵を切る, "clearing the tanka"). This is obviously an extremely aggressive gesture, since a fatal cut can be given in a fraction of a second thereafter (see iaidō). It is similar in connotation and effect as drawing back the hammer of a handgun, chambering a round on a pump-action shotgun, or pulling back and releasing the charging handle on other firearms.

The expression "tanka o kiru" is now widely used in Japan, in the sense of "getting ready to begin something", or "getting ready to speak", especially with an aggressive connotation.

The habaki will cause normal wear and tear on the koiguchi and either a shim or new saya may be needed to remedy the issue as it will become too loose over time. Oiling under the habaki after cutting or once every few months is recommended by removing the habaki from the sword, though.