Sandpaper coarseness is determined by the size of grit on the paper—ranging from extra-coarse to extra-fine. Using sandpaper that's too coarse could damage the material you're working with.

Sandpaper coarseness is determined by the size of grit on the paper—ranging from extra-coarse to extra-fine. Using sandpaper that's too coarse could damage the material you're working with.

Answer: The “grade” (or grit) of abrasive paper (sandpaper) refers to the size of the abrasive particles in the sandpaper. Given the same number of passes and the same amount of pressure ...