Sandpaper Grades Explained: Grades Chart, Grades For Paint & Sandpaper Grain
Sandpaper is a paper which has sand or any other abrasive material stuck to it and used to smoothen and polish wood and other surfaces. It belongs to a class of materials known as “coated abrasives” as it is made up of a flexible paper backing which has a thin film of glue (or any other adhesive) that holds and supports the coating of abrasive grains. The first usage of coated abrasives has been traced back to China when the Chinese people used crushed seashells, sand and seeds and glued it to a thin backing material using natural gum. Initially, sandpaper was known as glass paper as small particles of glass were used instead of sand grains.
Grades of Sandpaper and Their Uses
The sandpaper grades explained that there are several standards set for the coated abrasives but the common ones that are in use are sandpaper grades by the Federation of European Producers of Abrasives (FEPA) and sandpaper grades chart prepared by Coated Abrasives Manufacturer’s Institute (CAMI). Different grades of sandpaper have different uses. The chart prepared by FEPA is commonly used around the world as FEPA defines a grade by defining grain sizes range, unlike CAMI that defines the particle size on an average.
If you are looking for sandpaper grades explained then the different uses of sandpaper according to their grades have been thoroughly explained below:
- Sandpaper of grade between 24 and 36 is used to deburr concrete, paint and stone.
- Sandpaper of grade that falls between 24 and 60 is used to trim the surface of old paint and metal.
- 46-120 grade sandpaper is used to clean the surface of sandstone, brick and solid wood.
- Sandpaper grade of 60 to 120 is used to remove leftover paint stripper. It is also used to do sanding of the wood with the sandpaper grain. Scrubbing using these grades of sandpaper leaves the surface scratched, so a sandpaper of different grade is used to do the sanding again.
- For equalizing the surface layers of paint and old paint, 80 to 150 grade of sandpaper is used.
- Sandpaper grades falling between 120 and 180 are used to round the putty surfaces and equalize the sub-surface layer.
- 150-220 grades of sandpaper are used for equalizing surfaces, rounding wood pieces, wood veneer, wood trees, wood board of fiber, and board of particles.
- 180-220 sandpaper grades are unsuitable for sanding wood that is meant to be polished. These are used for preprocessing and equalizing solid wood or wood veneer after they are wetted.
- 180 to 400 sandpaper grades for paint are used for finishing work, sub-layer and putty.
- Sandpaper grade of 230 is used for lacquer sanding before the application of a primary layer of paint or a sub-layer of paint.
- Sandpaper of grades falling between 240 and 500 are used to give finishing touches to varnish and water varnish that is intermediate to the surfaces meant for sanding.
- 280 to 320 grades are used for sanding polyester and bare wood. It is also used for sanding the sub-layer before the finishing of application.
- Sandpaper of 320 grades is used for sanding varnishes.
- Sandpaper of 400 grades is used for sanding lacquer that has been freshly applied.
- Sandpaper grades of 400, 500 and 600 are helpful in removing blemishes, and film finishes so that it can be polished anytime in the future.
How to Use Sandpaper
Before you start your sanding job, decide how much material you want to remove from the surface. Choose the right grade of sandpaper as per the job you want to do. Hold the sandpaper against the surface with your finger tips or you can wrap it around a sanding block. Start with 60-grit sandpaper and move it back and forth if it’s wooden object, or move it in one direction if it is paint. Do not put excess pressure; sand it moderately and continue sanding until the surface is smooth and has become level. Next use a 100-grit sand paper and then 120-grit sandpaper until you can feel that the surface has become very smooth. Run your fingers over the surface; if you feel that it is as smooth as you would like it to be then your work is done. Finally, you can wipe the surface with tack cloth.
Surprising Ways to Use Sandpaper
You are aware of the general uses of different sandpaper grades but you will be surprised to know that the regular sandpaper can be used for many other works too. Below is a list of surprising ways to use sandpaper.
- If you are done away with a piece of sandpaper and you are ready to dump it in the bin then think again; the unused corners or edges of your sandpaper can be used to sharpen the sewing needles. Fold the used sandpaper and wrap it around the sewing needle; the sandpaper grain will make the needle sharper than before.
- Sandpaper not only sharpens your sewing needles but your cutting pair of scissors too. If you feel that your scissors are not cutting sharply and have become blunt then cut sandpaper with your scissors. This will sharpen the edges of your scissors and it will be sharper than ever. However, this will not work with all grades of sandpaper. This can be done using only fine grit sandpaper.
- Sandpaper can also be used to open your favorite jar of cookies that has been stuck. If you are having difficulties in opening your jar then wrap it around the lid of the jar and start rubbing it. After some time you will notice that the lid has become loose and you will be able to open up the jar. However, you have to make your that your grip is good enough to do the job.
- If your suede shoes or jacket has been stained then sandpaper will be helpful in removing the stain from it. If you spilled ink or there is any scuff mark on them, then gently rubbing it with fine-grit sandpaper will help to remove the stain or scuff mark off it.
- If there are fuzzy balls on your sweaters then you can take them off it by rubbing it lightly in any one direction. This can be done with any sandpaper grades.
- If the new pair of shoes that you bought is slippery then sandpaper grain can help make them rough. Take a little sandpaper and rub the sole of your shoes. This way you will have rough soles which will prevent you from slipping.