1) Normal size groove (=> 2) Double narrow grooves)
Making grooves on an Osoraku-zukrui tanto. Before that work, the blade has to be completely finished the shaping work with Arato stone.
Carve the body of groove with the plane.
Make the top of groove with the chisel.
The reverse side of the plane and the steel shavings. The tip of the plane is a super hard alloy.
Then the grooves are smoothed and shaped up with stones. The smith says this work is harder than the rough carving with plane.
There are various sizes and shapes of stones.
He grinds the stone frequently to keep its shape proper. Dull stones make the groove dull.
The grooves are running into the tang.
blade length 16.5cm
It is polished up in the classical style (Sashikomi).
2) Double narrow grooves
The blade is prepared that is completely shaped with Arato stone.
The tools: plane and guide.
Shape and smooth the grooves with chisel and stones.
The grooves are finished, and the blade is shaped with Binsui stone.
It is polished up in the modern style (Hadori).