1. Types
Sandpaper can be divided into two types: water sandpaper and dry sandpaper according to different usage methods.
Dry sandpaper: abrasives are bonded to latex with synthetic resin as a binder and coated with an antistatic coating. It has the characteristics of anti-blocking, anti-static, good softness, high wear resistance, etc., and is suitable for dry grinding.
Water sandpaper (water-resistant sandpaper): sandpaper with water-resistant paper or treated water-resistant paper as the base is called water sandpaper. It is usually made of paint or resin as a binder to firmly bond the abrasive to the base. It is used to polish the surface of metal or non-metal workpieces in water or oil.
2. Effect of Basis Weight
The unit of base weight of sandpaper, for example, AW is 65g/cm², which directly affects its bendability, toughness and mechanical resistance. Sandpapers of different weights are AW (A base weight), CW, DW, EW, FW, etc. from light to heavy. AW is the lightest and is usually used for manual sanding; CW is suitable for manual sanding and light mechanical sanding (portable vibrating sander); DW and above are for mechanical sanding; EW and FW are for heavy sanding. Different needs require different choices.
3. Raw Material
Dry sandpaper usually uses brown aluminum oxide, white aluminum oxide, zirconium fused alumina and other abrasives. The advantages are high grinding efficiency and not easy to stick to chips, which is suitable for dry grinding; water sandpaper usually uses corundum or silicon carbide abrasives, which have a fine texture and are suitable for grinding some things with fine textures and suitable for post-processing.
The choice of different types of sandpaper directly affects its performance in different environments.
4. Mesh
Mesh number refers to the number of mesh holes per inch of the screen, which is called the screen number, also known as mesh number. Therefore, the more mesh holes there are (i.e., the smaller the mesh holes), the larger the mesh number, which becomes an indicator of the fineness of the abrasive material particles and indirectly becomes an indicator of the fineness of sandpaper. For example, 100# sandpaper is made of 100-mesh abrasive, that is, the abrasive particles distributed on its surface are 150um.
The coarseness and type of abrasive of sandpaper greatly affect the use and effect of sandpaper. Here are some common sandpaper grits and their corresponding uses:
⑴ 40-60 mesh: This coarse abrasive is suitable for removing large pieces of material from rough surfaces, such as removing old paint, etc.
⑵ 80-120 mesh: These sandpaper grits are suitable for removing smaller defects, such as sharp edges or corners on wood or metal surfaces.
⑶ 150-180 mesh: This medium-grit sandpaper can be used to sand surfaces to make them smooth, such as removing thick layers of paint or coating.
⑷ 220-240 mesh: This type of sandpaper can be used to remove minor surface imperfections and create a smoother surface.
⑸ 280-320 mesh: This fine sandpaper is suitable for sanding and smoothing a variety of wood, metal and plastic surfaces.
⑹ 360-600 mesh: This ultra-fine grit sandpaper can be used to remove minor scratches on a surface and produce a very smooth surface, such as sanding an automobile surface.
⑺ 1000 and above mesh: This extremely fine sandpaper can be used for the most detailed sanding jobs, such as sanding eyeglass lenses, metal and plastic surfaces, etc.
