Sandpaper comes in a vast array of different grades and qualities designed for different sanding stages and purposes. Using the correct grade and type of sandpaper is essential in producing the best quality finish possible. Read on for more information on the various sandpaper types and grades available and the techniques used.
Types
Sandpaper comes in a variety of types and it is important to make sure that the correct paper for the job is selected. If, for example, you are working by hand, then the most common sandpaper to use would be an aluminum oxide paper. This includes working with sheet sandpaper and sanding blocks. Aluminum oxide can also be used on wood as well as metal finishes. However if you are using sanding machinery, such as sanding belts, then ceramic sandpaper is best. But if you are smoothing plastics, metals and joint compounds to a smooth finish, then the best choice of sandpaper would be silicon carbide. Silicon carbide is also the choice for sanding between coats of paint or finish. The only material silicon carbide is not suitable for is wood, due to its harder and sharper sanding quality. For wood it is best to stay with aluminum oxide paper.
Grading
Sandpaper comes in a great variety of grades and depending on the item you are working on the grades you will use varies. In general however, each sanding job requires three grades of sandpaper: course grade, medium grade and fine grade. Coarse grade sandpaper normally has a "grit" of between 40 and 60, meaning that it has a rougher texture suitable for sanding down many levels of the material being worked on. Medium grade paper has a "grit" of between 80 and 120, and is used for bringing the material down to a more level and smoother finish. Lastly, a fine grade sandpaper of between 150 and 180 is used on the material for creating a smooth to the touch finish. The lower the grade of sandpaper, the courser the sandpaper will be. The higher the grade of sandpaper, the smoother the sandpaper will be.
Technique
When sanding always sand in one direction only in order to create a smooth surface. With wood, make sure to sand along the grain and use an equal amount of pressure on each stroke. Whenever there is a buildup of sawdust or residue always blow off in order to make the sanding easier. This should be your basic sanding technique for all types of materials, whether wood, metals or plastics.
With sanding by hand it is a good idea to use a sanding block to help you apply an even amount of pressure onto. A sanding block can also help prevent the sandpaper from digging into or cutting the skin. It is also a good idea to use a dust mask and goggles whilst sanding to reduce the amount of dust particles that enter into your lungs or eyes. These types of safety measure are even more important if using sanding belts rather than sanding by hand. Always exercise caution and minimize risk when sanding.
Types
Sandpaper comes in a variety of types and it is important to make sure that the correct paper for the job is selected. If, for example, you are working by hand, then the most common sandpaper to use would be an aluminum oxide paper. This includes working with sheet sandpaper and sanding blocks. Aluminum oxide can also be used on wood as well as metal finishes. However if you are using sanding machinery, such as sanding belts, then ceramic sandpaper is best. But if you are smoothing plastics, metals and joint compounds to a smooth finish, then the best choice of sandpaper would be silicon carbide. Silicon carbide is also the choice for sanding between coats of paint or finish. The only material silicon carbide is not suitable for is wood, due to its harder and sharper sanding quality. For wood it is best to stay with aluminum oxide paper.
Grading
Sandpaper comes in a great variety of grades and depending on the item you are working on the grades you will use varies. In general however, each sanding job requires three grades of sandpaper: course grade, medium grade and fine grade. Coarse grade sandpaper normally has a "grit" of between 40 and 60, meaning that it has a rougher texture suitable for sanding down many levels of the material being worked on. Medium grade paper has a "grit" of between 80 and 120, and is used for bringing the material down to a more level and smoother finish. Lastly, a fine grade sandpaper of between 150 and 180 is used on the material for creating a smooth to the touch finish. The lower the grade of sandpaper, the courser the sandpaper will be. The higher the grade of sandpaper, the smoother the sandpaper will be.
Technique
When sanding always sand in one direction only in order to create a smooth surface. With wood, make sure to sand along the grain and use an equal amount of pressure on each stroke. Whenever there is a buildup of sawdust or residue always blow off in order to make the sanding easier. This should be your basic sanding technique for all types of materials, whether wood, metals or plastics.
With sanding by hand it is a good idea to use a sanding block to help you apply an even amount of pressure onto. A sanding block can also help prevent the sandpaper from digging into or cutting the skin. It is also a good idea to use a dust mask and goggles whilst sanding to reduce the amount of dust particles that enter into your lungs or eyes. These types of safety measure are even more important if using sanding belts rather than sanding by hand. Always exercise caution and minimize risk when sanding.
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