To polish Japanese katanas, be it katana or wakizashi, significant patience and care are required. An excellent polish significantly enhances a katana’s aesthetics and worth. A poor polish can irreversibly damage a blade by altering its shape. A primary recommendation in mastering katana polishing is to start with blades of lesser worth. “A key feature of the Japanese katana’s elegance lies in the hamon, also known as the temper line, concealed within its steel until revealed by the polisher.” It might be argued that the nature of a katana polisher, alternatively termed Togishi, unveils the katana’s essence and allure.
1.Uchigumori Stone
More finely grated stone utilized as the primary step in the polishing process advances. The blade is alternately maneuvered between stones, confirming the proper geometric shape and enhancing the texture of the surfaces. Proper molding of the stone is crucial for the blade’s uniform polishing. Nearby, a water pail is maintained to cleanse the katana after each sweep. It is the origin point of the name for Japanese waterproof stones.
2. Tiny Burning Needle –Migaki-bo
Should there be any bromine-rayed groove, it not polished with bigger stones. But instead with a tiny burning needle known as a migaki-bo. Utilizing these stones in polishing renders the steel’s firmer and more pliable segments more distinct and noticeable. The steel’s firmer, white section made up of tiny crystals. And the hamon brought into view upon light reflection from them.
3.Frequent Checks
Throughout this procedure, the polisher often reviews his work to confirm it aligns with the intended plan. Correct and quick molding is paramount. As a skilled polisher operates, the melodic sound of the blade gliding atop the stone is audible. Producing such a sound demands a vast amount of years of expertise. The initial, rough smoothing of the katana typically spans three days. It marks the completion of the first half of the polishing cycle.
4.Shiage togi or Finishing Polish
The initial phase of the polishing procedure resembles the method of polishing a katana. The blade glides over a solid stone. Known as Shiage togi or finishing polish, the latter part of the procedure involves using tinier, more delicate stones to enhance the blade’s refinement and eliminate any marks from larger stones. At this phase, the placement of the stone and blade inverted. Rather than the polisher shifting the blade over a larger, immobile stone, the Togishi keeps the blade fixed, allowing smaller stones to traverse it.
5.Slender Stone Paper Polishes
Using a sharp katana, a sizable stone divided into smaller segments, with each segment measuring approximately 2 or 3 mm thick. Subsequently, the stone’s thickness diminishes, followed by its adhesion to a unique paper known as washi using a highly durable adhesive lacquer. Annually, the polisher dedicates roughly a week to crafting these slender stone paper polishes. Meticulously, he employs a stone paper to refine each inch of the blade, thereby enhancing the aesthetic appeal of the steel.
6. Jizuya Finger Stones
When refurbishing a blade, particularly one that has undergone prior repairs. It’s crucial for the polisher to avoid extracting excess steel beyond what needed for effective polishing, to prevent harming the blade’s fine geometry. To preserve its initial shape, every part of the blade needs to meticulously polished at the precise, tiny angle needed, be it the spine, kissaki, or the cutting edge. This serves as further evidence of the Togishi’s endurance.
7.Hazuya
In the concluding phase, the slimmest stone fragments, famous as Hazuya, adhered to the washi paper. Its thickness approximates that of a typical postcard. The stones designed to eliminate minute scratches resulting from prior ones. Adequate illumination is essential in the polishing process to identify minor flaws and imperfections in the steel. With the usage of the paper, the stone layer diminishes in size and gradually fades away.
Final Thoughts
The full process of polishing a Japanese katana will take around 2 to 3 weeks from the basic polishing stage to the final, finer stages. To polish Japanese katanas, famous as nihonto, approximately 7 to 8 different whetstones used. And the katana further polished with 4 to 5 additional finishing steps involving ultra-fine hazuya and jizuya stones, as well as nugui powder to improve its visual appeal. The initial polishing stage, known as Shitaji togi, starts with a rough Uchigumori stone to complete the katanasmith’s initial rough shaping and eliminate all scratches and rust marks.