A Wakizashi or Katana might have a similar purpose as any other sword. However, these Japanese Samurai swords have a more exquisite look and a refined character than longswords and broadswords. Hence, Katana polishing demands extreme care and unparalleled patience.
A haphazard polish can ruin the blade (Nagasa) and disrupt the Katana’s exceptional geometry, leaving you with a Katana unworthy of admiration.
On the other hand, an excellent polish not only enhances the Katana’s beauty but also boosts the Samurai sword’s value. Unsurprisingly, only a master Japanese sword polisher (Togishi) can bring out a Katana’s beauty and soul.
Join us in exploring the equally mystical world of Katana polishing. We will examine Samurai sword polishing styles and stages necessary to reveal Katana’s unparalleled edge and elegance.
A Brief History of Katana Polishing
The history of Katana polishing is as ancient as ancient Japanese sword-making. Although no historian can say the process’s exact origins, most believe the art of Katana polishing started in the mid-Heian period (794 to 1185 AD).
Katana polishing served a different purpose way back then. Togishi refined the Katana’s edge to improve the sword’s ability to cut, slash, and pierce. A razor-sharp Nagasa allowed Samurai warriors to defeat opponents with as few strikes as possible.
Today, Katana polishing takes on a more aesthetic value. Nobody can deny the Katana’s unrivaled elegance, with its characteristic moderately curved blade and an equally iconic temper line (hamon) demarcating the light yet sharp edge and the dark but durable spine in various patterns. It’s Togishi’s responsibility to bring these characteristics to life.
Unlike other sword polishing techniques, Katana polishing is a generational affair. Like Katana-kaji, one cannot become a Togishi without learning and mastering the ancient art of Katana polishing. Unfortunately, very few in 21st-century Japan have this distinction.
Modern Toshigi are descendants of Hon’ami Myohon. Honami served as a Dobo-shu under the shogun, Ashikaga Takauji (1305-1358), and started a family business caring, polishing, and valuing Katana and other Japanese swords for centuries. Although the Meiji Restoration saw the Samurai’s demise and the closing of shops of different Hon’ami offshoots, the Soke family chose to carry on the Katana polishing tradition.
A Hon’ami descendant – Hon’ami Mitsuhisa – published “The Rules and Characteristics of Japanese Swords” in 1955, which became one of the most revered books on Katana evaluation.
A Togishi’s Katana polishing essentials. Photo by Andrew Ickeringill.
2 Styles of Polishing Samurai Swords
Nobody likes a lackluster sword, especially a Katana. Everyone wants that characteristic glimmer when light strikes the blade as the person holds the Samurai sword in one hand. It is a mesmerizing work of art, and only a Togishi can make a Katana sparkle as the Katana-kaji envisions it.
Toshigi uses different polishing styles to bring out the gem in every Katana. Although authentic Japanese Katana features only Tamahagane steel, some bladesmiths might use other materials (i.e., stainless steel and other high-carbon steel). Some swordsmiths also vary in tempering processes, giving their Katana swords distinct characteristics.
Still, Katana polishing often requires one of two blade finishing techniques or styles, allowing a Togishi to elevate the sword’s unmatched beauty.
Hadori
The Hadori Katana polishing style is exclusive to clay-tempered Samurai swords. As mentioned, each Katana-kaji (a traditional Japanese swordsmith) has a “secret” blend of ingredients used in tempering a Katana, giving it exceptional strength and flexibility. Although clay-tempered Samurai swords require “clay,” individual Katana-kaji might add other ingredients to achieve the desired sword qualities.
A Togishi specializing in the Hadori style uses a Hadori stone revered for its coarseness. The polisher rubs the Katana’s Nagasa on the Hadori stone, paying careful attention to the Hamon’s fine edges. Patience is a virtue in the Hadori style, allowing the Togishi to highlight the Hamon’s shape and give the Katana its attractive, mesmerizing look.
Historians say a Togishi spends countless hours polishing the Katana with single-minded dedication – a trait few 21st-century folks can muster.
It is worth noting that the quality of Katana polishing using this style depends on the Hamon, the Togishi’s skill, and available equipment. No amount of Hadori polishing will bring out Hamon’s best qualities if the latter is not inherently beautiful. Likewise, an elegant Hamon will stay hidden in the hands of an unskilled Togishi.
A sub-style of Hadori Katana polishing is “feather Hadori.” This style is a notch above conventional Hadori polishing techniques, requiring the Togishi to focus more on the Hamon. This style demands the Togishi to create distinct deep lines on the Hamon to produce a bird’s feather-like texture. If a Hadori-polished Katana is beautiful, a feather Hadori-refined Samurai sword would be out of this world.
A Hadori-style Katana polishing. Photo by KSKY.
Sashikomi Nugui
If the Hadori Katana polishing style requires a special “water stone” to reveal the Hamon’s impressive beauty, the Sashikomi Nugui style elevates it.
This technique can take several days to weeks to complete, using a unique blend of iron sand (Satetsu) and clove oil to highlight the Katana’s Ha (the razor-sharp edge) and darken the Nagasa’s surface.
Before the Togishi applies the nugui mixture, he polishes the Hamon and Jihada (the blade’s grain or texture) against a Hazuya stone. The Hazuya is an Uchigumori polishing stone with a sandpaper grit equivalent of 3000 to 5000 grit.
The Togishi then polishes the Nagasa using a Jizuya stone. This stone is harder and finer than Hazuya and works to clarify the Tamahagane steel’s natural color and unique patterns.
Although most Togishi use Satetsu and clove oil, some mix Tsushima and other magnetite compounds with other “secret” ingredients to produce a desired Jihada color. The Nugui application preserves the Hamon’s beauty by lightening the Hamon and darkening the surrounding areas. This technique is only suitable for Samurai swords with well-defined grain patterns and Hamons.
A Sashikomi Nugui-style Katana polishing. Photo by KSKY.
2 Stages of Katana Polishing
The Hadori and Sashikomi Nugui Katana polishing styles help bring out Katana’s unrivaled elegance. However, these are blade-finishing processes meant to highlight the Hamon. Before a Togishi can apply these finishes, the Katana must undergo two stages of Katana polishing – Shitaji Togi and Shiage Togi.
Stage 1: Shitaji Togi – The Foundation Polish
Right after forging, the Katana-kaji gives the Katana to a Toshigi for initial or foundation polishing. The Toshigi starts polishing the Katana with the same grit as the Katana-kaji used before giving the Katana.
For example, if the Katana-kaji used a #700 water stone, the Toshigi must start the Shitaji Togi with #700 before progressing to finer-grit polishers.
The Togishi observes the following steps.
- Prepare the polishing platform Togi-dai to collect swarf and water during Katana polishing.
- Flatten and shape each water stone (with progressively finer grit ratings) using a diamond stone to chamfer the edges and remove saw marks.
- Polish the Katana using #500, #700, or whatever grit value the Katana-kaji last used. This action removes any remaining Kongo-do or Arato stone scratches.
- Polish the Katana with the natural stone Binsui-do to refine the Nagasa’s shape and make subtle changes.
- Remove Binsui-do scratches from the Nagasa using a synthetic #1000 polisher. The Togishi runs the Katana nearly parallel or steeply diagonal to the Nagasa’s length.
- Eliminate the #1000 synthetic polisher’s scratch marks from the blade using natural Kaisei-do along the Katana’s length.
- Use Chu-Nagura-do to polish the blade and remove scratch marks left by the Kaisei-do. From this point onward, the Togishi must only polish the Katana lengthwise or along the sword’s length to achieve the classic Katana look.
- Increase the Ha’s (the Katana’s sharp edge) polish level using the white Komanaguro-do polishing stone.
- Determine if the Katana requires more blade refinement using finer-grit polishing stones.
The Shitaji Togi prepares the Katana for the finishing touches, eliminating irregularities, and maintaining the Nagasa’s sleek look and geometric shape.
A Chu-nagura-do for Katana polishing. Phot by Tomo Nagura.
Stage 2: Shiage Togi – The Finishing Polish
Applying Shiage Togi to a Katana demands focus and patience. The process can take as long as all other Katana-making processes combined. A Togishi uses an Uchigumori water stone and smaller finger stones for the Katana’s finishing polish. These materials are necessary to give the Katana its legendary look. Shiage Togi involves the following.
- Focus on the Nagasa’s transition area between the Ji and Ha using a Suita-uchigumori-do. This step is laborious and time-consuming because it requires the Togishi to apply constant pressure on the blade as it glides on the water stone. The Togishi can use other Uchigumori types to match the Katana’s steel and hardness.
- Use natural Narutaki-do to polish the Nagasa’s Ji section.
- Use Narutaki-do and Uchigumori-do koppa-derived Hazuya and Jizuya to add depth and even the Nagasa’s surface. The Togishi attaches these finger stones to natural Urushi-embedded Washi paper.
A Hazuya (left) and Jizuya (right) finger stone for Katana polishing. Photo by WorthPoint.
The Togishi uses finger stones to carefully polish each square centimeter of the Nagasa at a time. It is a painstaking process that requires eagle eyes and unmatched attention to detail. They must choose the correct finger stone to smoothen Uchigumori-related unevenness and other scuffs. The process culminates in pouring boiling water over the Nagasa to prepare it for Sashikomi Nugui finishing.
The Bottom Line
Although the purpose is identical, Katana polishing is more demanding than polishing and sharpening other swords and bladed tools (including knives). Unsurprisingly, only skilled Togishi can bring out Katana’s unrivaled beauty, elegance, and cutting-edge precision. And if you want to restore your Katana’s mystic charm, let a professional do it for you.
