What Grit Sandpaper Should You Use to Prep for Paint?- what is the best grit sandpaper for wood ,This simply means, the lower the grit number, the coarser the grains of sand or abrasive material will be. Conversely, the higher the grit number, the finer the grits or grains of sand or abrasive material will be. Although coarser sandpaper will remove more material from the surface, it will also leave deep scratches as well.Using the Right Sandpaper for Your Project14/8/2019· Sandpaper is graded based upon the number of abrasive particles per square inch that make up the sandpaper. The lower the number, the more coarse the grit. Sandpapers are commonly graded as coarse (40 to 60 grit), Medium (80 to 120), Fine (150 to 180), Very Fine (220 to 240), Extra Fine (280 to 320) and Super Fine (360 and above).