Figure 1 - Sandpaper types and sizes
The following information should help the home handyman determine which type and grit size sandpaper to use for a specific project.
The home handyman should be concerned about two items - grit size and grit material.
Sandpaper is sold by the amount of grit that it takes to cover one square inch of the sandpaper. As an example, a 100 grit sandpaper has 100 pieces of grit on each square inch of the paper.
Grit Size & Functionality Chart
Grit
40-60
Nomenclature
Coarse
Function
Brute strength sandpaper - can leave deep gouges in material being sanded - used to remove heavy paint layers and as an initial sanding on badly dented and marked hardwood flooring.
80-120
Medium
Used to level wood surfaces and to remove smaller gouges and light layers of paint or stain.
150-180
Fine
Final sanding before applying paint or sealers. Will remove surface scratches from hardwood flooring.
220-240
Very Fine
Used for sanding between coats of varnish, urethane and shellac.
280-320
Extra Fine
When working with furniture an extra fine sandpaper is used to remove slight imperfections between finishing coats of urethane or varnish.
360-600
Super Fine
Primarily used in high finish requirements between coats of car lacquers or expensive furniture - will dull luster somewhat providing a base for an additional coat.
Sandpaper is available in many physical sizes depending on the power sander, sanding machine or block that it must fit.
There are different grit materials available, while sandpaper was originally sand glued to paper, sand is no longer used as an abrasive on sandpaper. Some grits are better than others when sanding certain materials.