Japanese swords remain to be commonly seen. Both antique and modernly-forged swords are easily found and purchased. Modern, authentic nihontō are made by a few hundred sword smiths. Numerous Japanese swords are showcased at contests hosted by the All-Japan Swordsmiths Association. We may constantly look at Japanese swords with amazement at the fine details and their extreme sharpness. Let’s get to know each parts and anatomy of Japanese swords.
Kashira
This is the metal fixture at the very base of the sword hilt. It mainly serves its purpose as a decoration.
Tsuka ito
It is usually made of leather or silk cord. This is the wrapping material that creates the grip pattern of the sword hilt. It should be wounded very tightly and neatly. Poor craftsmanship often produces protruding loose ends or loose binding that can come undone over time. However, it is expected that over time the tsuka needs to be retied or have it replaced completely by a professional due to simple wear and tear.
Tsuka
It serves as a handle or hilt of the sword made of a strong wood. Its function is to provide both impact absorption and shock tolerance. Its width is at least long enough for two hands to grip it comfortably. It is often longer to create more leverage and control of the sword.
Tsuba
It separates the blade from the handle. It is the hand guard shaped circular or sometimes square or octagonal. The tusba is associated with art and long history. It may function as a simple hand guard yet its craftsmanship and design have become equally important in samurai culture. The designs can be cranes, to dragon flies, to clan symbols, to poetic scenery among the virtually endless design possibilities. The highest potential of artistic freedom is found in this part of the sword.
Habaki
The habaki encircles the base of the blade just above the tsuba. Its dual purpose namely are to lock the tsuba into place and also to secure the sword in its scabbard. Habaki and saya is interrelated, the two pieces must fit together like a glove. The habaki and saya opening (or the “throat”) must fit snugly enough so that the sword will not accidentally slide out on its own, but loose enough that the sword can be “popped out” by the thumb. It’s common for a brand new saya and habaki to feel a bit tight. It will loosen up after several draws. The tightness of the brand new saya doesn’t make it difficulty for as long as you can draw the sword without wrestling it loose
Shinogi
The grinded blade portion ends at the ridge of the sword known as the shinogi. The shinogi is the thick part of the sword. Different angles and thicknesses can produce subtle differences in the sword’s ability to cut at various angles and through various substances. However, the beginner sword owner shouldn’t be concerned with these details right away.
Ha
Ha is the overall sharp edge of the sword.
Hi
The “blood groove” of the sword called the hi guides the blood away from the samurai and drip off the sword. In fact, the groove has nothing to do with blood. It is carved into the blade to lighten the sword without weakening it and to remove inherent flaws in the steel. The “blood groove” legend was an after-thought invented mostly by westerners to further mythologize the samurai sword.
Mune
Mune is the flat, non-sharp back or “spine” of the sword. It is a purposely more soft metal than the sharpened edge. The contrast of hard and soft metals is one of the main characteristics of the swords. It makes the samurai sword so strong, resilient, and unique among swords. The mune is almost never sharpened. In a few rare cases, the upper portion of the mune is sharpened to create a double-edged sword although extremely rare. The flattened mune is also functional in deflecting enemy sword blows.
Boshi
This is the edge pattern (hamon) on the curved portion of the tip of the blade. It is a decoration and should not be confused with kissaki.
Same
Same is the ray skin or stingray skin that covers the handle of the sword and lays underneath the cord wrap (tsuka ito). Ray skin is the traditional material used in Japanese sword making. It is the best choice as materials because it’s slightly textured (for better gripping) and it’s waterproof. However, imitation ray skin or leather is just as good and will not hinder the performance of the sword in any way.
Sageo
The cord made of silk or cotton that is used to tie a sword’s scabbard (saya) to the obi of a samurai is called sageo. It is usually kept bound to the saya and never actually tied to the obi for everyday use. Samurai would remove their long sword every time they sat down, and tying and untying the cord would be too much trouble. The samurai would, however, use the sageo to tie the saya to their obi on the battle field to prevent the saya from being lost. There are some who claim that this length of cord could also be used as a rope on the battle field to tie up prisoners or simply used as a spare length of cord when needed. It is tied in various decorative patterns.
Saya
This is the scabbard where the sword “lives” when not in use. It’s usually made of two halves of custom-carved wood sealed together to form a snug fit around that particular blade. The wood is usually highly laquored and sometimes highly decorated. The saya’s relation to the habaki (sword collar) is vital: the two pieces must fit together like a glove. The habaki and saya opening (the “throat”) must be snug enough so that the sword will not accidentally slide out on its own, but loose enough that the sword can be “popped out” by the thumb. It’s common for a brand new saya and habaki to feel a bit tight. As long as you can draw the sword without wrestling it loose, it should loosen up after several draws.
Hamon
The wavy blade pattern of the sharpened portion of the sword is called the hamon. It is a visual effect caused by the tempering process. It serves as a division between the harder edges of the blade with the softer ridge. The pattern is merely the result from the tempering process. During tempering process, the sword smith tries to create a desired transition between the soft and hard metals. Most modern reproductions do not have natural hamon. Their hamon is faked by various processes such as acid etch or more crude ones such as wire brushing. Some modern reproductions with natural hamon are also subjected to acid etching to enhance that hamon’s prominence. However, the lack of a “natural” hamon should not deter you from purchasing an otherwise fine sword.
Kissaki
This is the very pointed area of the sword. It’s often confused with the Boshi. The Boshi is just the wavy hamon design while the kissaki is actual point area. Its length, width and point angle has varied over time depending on the conditions in which the sword was used. Some angles manufactured have slightly better piercing performance intended as armor while others for non-armor use. Other kissaki designs are plainly decorative statements of a samurai’s status. The beginning sword owner should not worry about the kissaki too much for it won’t hinder the overall performance of the blade.