Sharpening a Knife at Hirotomo Knifeworks
Coarse grinding: A knife is ground very close to its final form before being hardened in a furnace. The craftsman has only a grinding rest to help steady his hand during the process. The knives' final form is the result of a keen eye for the shape and a feel for the material gained by years of training and experience.
Wet grinding: The final sharpening happens after the hardening, and so must be done on a water-cooled sharpening wheel. The water cooling is necessary because a dry wheel would quickly heat the blade to the point where the furnace-hardening process would be reversed.
The blade blank is clamped in a wooden jig and then sharpened freehand. The sharpeners half-stand and half lay over the machine on a kind of pillow fastened to its top. It takes at least three years of training and practice to learn to properly sharpen a knife using this technique.