In the old days, “sandpaper” could be defined as being “actual grains of sand that are glued onto a paper backing.” Nowadays, “sandpaper” can be defined as abrasive grit that is attached to a strong paper backing or cloth. Actual grains of sand are no longer used. Instead, the grit is now composed of aluminum oxide, silicon carbide, and garnet.
Whatever the grit is made from, sandpaper is the “paper of choice” when it comes to removing, smoothing, sharpening, polishing, and shaping objects and materials. There are several different types of sandpaper for many different applications. In order to use sandpaper fast and effectively, you will need to choose the proper type for the project you are working on.
It can be rather confusing figuring out what grit, as well as what grit size you need, for every application. Many times, if you are sanding coats of paint, for example, the paint container will instruct you on what type of sandpaper to use; that’s an added plus!
A number represents the size of the grit. The number, in turn, is used to grade the sandpaper. On the high and low ends of the scale, forty is the coarsest (largest) grade grit, while four hundred is the finest (smallest) grit available. In between that, fifty to sixty grade is still coarse; eighty to one hundred is considered medium coarse; one hundred and twenty to one hundred and fifty is medium coarse; one hundred and eighty to two hundred and twenty is considered fine; and two hundred and forty and up is a very fine grade of sandpaper.
Now, as for the types of sandpaper, the aluminum oxide is suitable for many applications because it is sharp. It allows you to sand down an object or surface fast and effectively. The silicon carbide is suitable for sanding in between coats of wood finishes, such as varnish or polyurethane. And, finally, the garnet – grit sandpaper is great for smoothing out scratches made by previous sanding. You can easily identify what type of sandpaper you have by checking the paper backing. Every piece is marked with the grit size or with the grade number.
There are also two types of sandpaper in regards to the pattern of the grit. If a piece of sandpaper is considered to be a “closed grit”, that means that it is completely covered with grit. If a piece is considered to be an “open grit”, that means that only about fifty per cent of the paper is covered with grit. While the “closed grit” sandpaper can work fast and effectively, it can often tend to clog up with the material that is being sanded.
In order to use sandpaper fast and effectively, you need to always choose and use the correct type for the project at hand. If you want to end up with a smooth surface, you will need to start with a coarse paper. Then, as you sand the surface down, keep changing the grade of the sandpaper you are using until the surface reaches its desired smoothness.
Don’t use excessive force when you are using sandpaper either. This will only cause the sandpaper to wear out prematurely. It can also damage the surface that you are sanding. Allow the paper to do the work for you!
When you are sanding wood, be sure that you move the sandpaper in the same direction as the wood grain. This practice will help avoid making scratches in the wood and roughening up the grain. On all other surfaces, you should move the sandpaper in a circular motion.
Finally, in order to use sandpaper fast and effectively, make sure to stop periodically and check the grit of the piece. If it is clogged up with the material that is being sanded, clean coarse grit out with a brush. If the grit is fine, you can use an old, rough cloth.Finally