Sandpaper is a high-grade product made of synthetic resin as binder, silicon carbide abrasive bonded to latex, and antistatic coating, which has the characteristics of anti-adhesion, anti-static, good flexibility and good wear resistance.
Preparation before grinding:
Don't rush to sharpen the sword after you get it. It is necessary to take time to observe the knife in your hand. Honami's book "Honami's Behavior" records his polishing experience. It says that "a fine craftsman works with a knife in his hand and observes it repeatedly for ten or twenty days until he understands it".
A knife that needs polishing will have many problems to repair. The most common ones are corrosion and pitting, edge collapse, head cutting and breaking, edge bending, etc. The newly made Dao will also have defects on the blade body because of the craftsman's production problems, which needs full observation and research.