As a Sandpaper Manufacturer, share with you.
Sandpaper is not made of sand, but is composed of fine particles of natural or synthetic origin. The particles are sieved through a screen and classified by size, and then bonded to paper, sponge or cloth-type backing with an adhesive to make self-use abrasives.
The requirements of each project are different, so it is important to distinguish the grain size of sandpaper.
This means:
The higher the number, the smaller the particles, and the finer the sandpaper particle size.
Conversely, lower numbers indicate larger grains and overall rougher sandpaper.
In order to facilitate people's choice, in addition to specifying the grade, the manufacturer will also mark a "rough grade" on the package. It is actually a range of particle size, suitable for similar grinding work.
In fact, most woodwork projects only need to choose a certain rough grade of sandpaper, and it does not have to be accurate to a specific sandpaper particle size. Therefore, it is very important to know the applicable items for each grade.
Ultra-coarse sandpaper has a particle size range of 24-36 mesh, used to remove paints and varnishes that are difficult to peel off.
The strength of coarse sandpaper is to roughen wood and remove finishes, such as light-colored polyurethane coatings. Coarse particles are usually in the range of 40-50 particle size.
Medium sandpaper, with a particle size range of 60-100 mesh, suitable for the last sanding before painting. Usually we also use medium-grain sandpaper for preliminary sanding of rough wood to remove planning marks on the wood.
The particle size of fine sandpaper is 120-220 mesh. For most home workshops, this kind of sandpaper is sufficient for the final sanding before the work is completed.
Superfine sandpaper is often used between paint or varnish. Abrasives of 240 mesh, 320 mesh and 400 mesh are called very fine abrasives, and special grade or ultrafine abrasives with a particle size of up to 600 mesh are most suitable for polishing operations.
Note: In many projects, you have to start with the rough sandpaper mesh, and then change to a finer mesh to get a smooth surface effect.
Our company also has Custom Sanding Belts on sale, welcome to contact us.