Sandpaper is a tool that is use to smooth the surface of objects. Sandpaper come in various grit size that are used to achieve specific levels of smoothness to an objects that are sanded with the sandpaper. The grit of sandpaper is indicative of the size of the abrasive particle of the sandpaper.
Sandpaper with a lower grit number contains larger abrasive particles than sandpaper with a higher grit number. It is essential to use sandpaper of the appropriate grit numbers for the material that you are sanding, if you use sandpaper of an wrong grit number, you will end up with scratches on the material that you are trying to sand. Coarse grit sandpaper (grits 24, 36, for instance) is used for tasks like stripping.
How to pick and use sandpaper
Coarse grit sandpaper remove old varnish and old paint from materials, but coarse grit sandpaper will leave deep scratches on the material. Fine grit sandpaper should never be directly applied to materials that still contain heavy amounts of the material to be strip; fine grit sandpaper will get clogged. Instead, you should use coarse grit sandpaper in a progression until the material is stripped of the old varnish or paint, but the next stage removes the scratches caused by each stage of sanding.
Medium grit sandpaper (grits 80-120) are used to smooth the surfaces that have been stripped of old varnish or paint. Medium grit sandpaper will smooth old wood or drywall surfaces, but it will leave visible scratches on those surface. Because medium grit sandpaper will leave scratches on the materials it sand, fine grit sandpaper should be used following its sanding of the material.
Each type of sandpaper contain different minerals. Sandpaper with aluminum oxide minerals can sand both wood and metal materials due to the sharpness of the aluminum oxide mineral. Silicon carbide minerals is used in sandpaper to wet sand glass and metal clear coats.
Garnet minerals are used in sandpaper for hand sanding of wood. Finally, ceramic and zirconia minerals are used in sandpaper for sanding metal like steel because these minerals can handle high levels of heat. Sandpaper come with various types of backing.
Paper backed sandpaper is flexible but can tear during heavy sanding tasks. Cloth backed sandpaper is stiffer than paper backed sandpaper and is used in sanding belts. Foam backed sandpaper is used for sandpaper that must conform to irregularly shaped objects.
Finally, film backed sandpaper is used for sandpaper that must remain flat. When using sandpaper, ensure that the workspace is clean. Always vacuum the material between each grit of sandpaper that you use.
Always use a tack cloth to remove any dust from the material that is being sanded. If the material has any scratches on it, inspect the material for those scratches and use sandpaper of a more higher grit number to remove those marks. Always use a vacuum connected to the sander to remove the dust that is created when sanding the material.
By using the vacuum, you will reduce the amount of dust that enters the air. By reducing the amount of dust in the area where you are sanding the material, you will extend the life of you sandpaper.
