Sharpening Nihonto

[Aldebaran]

CLEANING
The politore (togishi) works with a range of natural stone with a variety of abrasive power, the transaction must respect and enhance the geometry of the blade masterfully produced by the swordsmith. The polishing is done in two phases: shitajitogi and shiagetogi.


SHITAJIDOGI

Continue for short sections and treating one side at a time, initially using three stones (plowed, and binsui kaisei), with which you define the exact geometry of the blades already set by the swordsmith. The blade is passed over the stone setting (never the reverse), with different angles of incidence, each stone next remove the traces left by previous.
After you pass the stone nagura on which the blade is passed longitudinally and with a slight rocking motion that makes visible the profile dell'hamon.
Finally we come to uchigumori stone, which serves to highlight the details of forging steel.


SHIAGETOGI

At this stage of polishing abrasives are used increasingly for. The stones are used in a minimum thickness of less than a millimeter, and pass on the blade held fixed, unlike the previous procedure.
It begins with hazuya (uchigumori flakes), which is used in squares of 2.5 cm and 0.1 mm thick. The hazuya is passed on the blade, together with a paste lubricant (tojiru) consists of a mush of water and dust uchigumori, working from shinogi the wire, again for small areas at a time during this procedure Boshi (tip of the blade) is not touched. The blade takes on a whitish color, and if the operations were well followed, the procedure is of short duration, followed by the polishing of ji, an operation that will make the blade of a darker color and gloss.
Across the blade (always with the exception of the tip) is now past the nugui a suspension in vegetable oil iron oxide residue of forging processes. This process serves to darken the? Steel and highlight details and? considered very important, so that each has its own recipe politore nugui.
The mating process, however, serves to highlight the color difference between ji and ha (edge defined by hamon), and is accomplished by a stone hazuya cut into an oval shape.
The last tip is polisce (boshi) isolating the rest of the already polished blade cover with cotton fabric and defining the Yokote (edge separation between the tip and the blade) with a strip of bamboo, past the tip on a square hazuya glued on a pad of paper in turn placed at the end of an instrument of wood. The final aspect of Bosch and satin and contrasting with the rest of the blade.


Mikage

Polishing complete polishing operations, the common and shinogiji (the spine and the plate of the blade) are polished with Mikage-bo, small steel rods that hard, fast rubbing on steel, making it compact the surface gloss and reflective.

In any case, each blade requires stones suitable to their peculiar constitution, for which the togishi will have a wide range of materials to enhance the features of each sword, which will be carefully studied prior to polishing.