匠の技について
Understanding ミラーポリッシュ
The Mirror Polish is a process involves several step that gradually brings a rough surface with diffuse reflection to a mirror-like surface with nearly pure specular reflection. These steps usually consisting polishing the metallic surface with various abrasives, progressing from low-grit/corse abrasives to hight-grit/polishing abrasives.
First, the blade is throughly cleaned with detergent or solvent to ensure there is no residue of any form that will affect the polish, this will be performed repetitively to prevent coarse grits not being carried to the next step. The rough grinding then takes place to remove major dents and scratches from the forging process. The blade is then smoothed and polished with a finer grit abrasive, its uniform surface will look like a Migaki or satin finish that are found on other knives. The final polishing and buffing step will use powder-form abrasives, rated above 10,000 grits and applied on soft base like buffing wheel or belt, to take away the last bit of roughtness. By the end of these steps the knife will have a surface with only specular reflection, acting like a mirror.
A finely done Mirror Polish will give a blade additional value with the extensive labour behind it, but the obvious pros of this finish is the delicate look it gives to the blade. It can increase the contrast of some damascus pattern, Hamon on a Honyaki can pop more on this uniform background, even the blade is just a simple monosteel construction, the mecury-like metallic surface can ofent make one hold breath.
The cons of this finish is equally obvious, although the food that a kitchen knife will cut are not going to damage it, contact with harder objects like other metallic utensils will likely to do leave a noticeable scratch on it. This virtually perfect surface also means any dents or warps will be revealed under the light. On one hand it means manufacturers are confident with their product when they put this finish on their product, but this also means the labour and quality control will lead to a bigger pricetag.
