Sandpaper, as known as abrasive paper, which is a material used for grinding and polishing, usually an abrasive coated with this kind of grinding sand on the surface of a piece of paper. Sandpaper is mainly used to grind the surface of metal or wood to remove the substances as well as making the surface smooth and clean. Nowadays, sandpaper no longer uses sand as grinding material but instead uses alumina or silicon carbide. The difference between sandpaper and other grinding tools is that sandpaper can only remove impurities on the surface of the object, but cannot sharpen the object. According to different abrasive materials, we can be divided into many different types, such as emery paper, flint, garnet, and so on.
The two most common sandpapers are dry sandpaper and water sandpaper. Dry sanding paper is mainly made of synthetic resin as a binder, and then silicon carbide abrasive is bonded to the binder. Dry sanding paper has good softness, anti-static, anti-clogging, and high abrasion resistance. Usually, dry sanding paper is made of latex paper or kraft paper. It is widely used in the furniture manufacturing and decoration industry for rough grinding purposes which is mainly used to polish wood, metal, and other materials. Another is water sandpaper, which is characterized by the process of polishing in the water. Water sandpaper is composed of water-resistant paper and an adhesive coated with paint or resin on the surface. The sand of water sandpaper also uses silicon carbide. The dust polished by water sandpaper is relatively fine. If it is polished in water, the dust will float on the surface of the water instead of floating in the air. Due to the texture of water sandpaper being relatively fine, it is mostly used to polish fine items.
Types of Abrasive paper
In the market, we can find most of these five types of sandpaper, such as alumina, emery, flint, garnet, and silicon carbide.
Alumina Sandpaper
Alumina sandpaper is a synthetic abrasive, so it is more wear-resistant and harder than other types of sandpaper. The color of alumina sandpaper is mainly brown. Although the cost of alumina sandpaper is relatively high, it has a long service life, so most projects still choose to use alumina sandpaper. Alumina sandpaper can be used on a variety of surfaces such as metal, wood, and paint.
Emery Sandpaper
Emery paper is a kind of sandpaper that contains natural minerals and elements. Due to the stable structure of the emery particles and the same size, the emery paper has higher precision and can make the surface smoother. These advantages make emery paper a high-end metal processing abrasive product. Emery paper is mainly used for polishing large areas, removing paint, removing rust, etc.
Flint Sandpaper
Flint sandpaper is made of natural minerals and the color is beige. Although the cost of flint sandpaper is relatively cheap, it is not wear-resistant compared with other types of sandpaper. Therefore, people need to change it frequently. Flint sandpaper is suitable for some smaller processing projects.
Garnet Sandpaper
Garnet sandpaper is also made of natural minerals. Its wear rate is the fastest, but it can produce the smoothest surface. The color of garnet sandpaper is mainly red or golden brown. Generally applicable to wood manufacturing.
Silicon Carbide Sandpaper
Silicon carbide sandpaper is a synthetic abrasive that is harder than alumina sandpaper. Therefore, compared with alumina sandpaper, silicon carbide sandpaper can polish harder metals and plastics. Its color is mainly black or charcoal. Silicon carbide sandpaper is often used to grind the floors and polish the glass, ceramic or hard plastic surfaces. Besides, silicon carbide sandpaper can be used on wet surfaces as well.
The number of sandpaper refers to the thickness of the abrasive grains in the sandpaper. The larger the number, the finer the abrasive grains. Sandpaper with larger particles is rougher than sandpaper with smaller particles. Therefore, sandpaper with a higher number is suitable for work that requires fine grinding, while sandpaper with a lower number is suitable for work that requires rough grinding. Generally, the number of sandpaper is 30, 60, 120, 180, 240, etc. The lower number 30 is used for rough grinding, while the higher number 240 is used for fine grinding, mainly to remove surface defects and make the surface smoother. The number in the middle can be selected according to the needs of polishing. Since rough sandpaper is easy to leave scratches on the surface, we need to test it before choosing the right sandpaper.
The manufacturing process of sandpaper
Put the emery cloth into a machine with a printing function, and this machine will print the adhesive onto the emery cloth. Then use electrostatic treatment to move the emery cloth with adhesive to the roll with grit. Due to the electrostatic electric field, sand particles will be attracted to the emery cloth. In this way, the sand particles can be evenly distributed on the emery cloth. If we need to absorb larger sand particles, we need to increase the electrostatic current and voltage.
Contact MecHero right now to get the sandpaper for your polishing project. Send your inquiry to 011-7000 7687 or my.mechero@gmail.com