The next very important step after finishing any wood work is polishing. Whether you choose to use any type of electric sander or hand sanding, you will need to choose the right type of sandpaper and grit. Using the wrong sandpaper can cause irreparable damage to your work, so this step is especially important.
Choose the right grit
Sandpaper is graded based on the number of abrasive particles per square inch that make up the sandpaper. The lower the number, the coarser the grit. Sandpaper is usually divided into coarse (40 to 60 grains), medium (80 to 120 grains), fine (150 to 180 grains), very fine (220 to 240 grains), ultra-fine (280 to 320 grains), and finer than ultra-fine (360 grains and above). Sanding with progressively finer grit removes the scratches left by the previous gritty sandpaper and eventually leaves a smooth surface. The author said that some of our commonly used models are 400# 600# 1000# 1200# 1500# 2000#.
You may ask, "Why can't I sand the whole process with fine sandpaper?" What I want to say is, well, there's nothing to say that you can't, but coarse sandpaper will quickly remove excess rough material, and then sand with finer sandpaper, so that the surface of the work becomes smoother, which will also make the whole process of sanding easier and faster. And almost all experienced woodworkers will tell beginners that the sooner the work is polished, the better.
Graded sandpaper
There are two main types of sandpaper: commercial grade and industrial grade. The difference is in its composition, which is the material used as the grit, the backing material (paper) and the glue used to keep the grit on the paper. The industrial grade uses higher quality materials to handle all three components.
In addition, you may see sandpaper that is rated as "open" or "closed" jacket. The difference is that closed sandpaper has more tightly grouped grit particles, where open type sandpaper has a larger gap between the particles. As a general rule, open sandpaper is generally better for woodworking because it doesn't clog as often, especially when using softwood that contains more resin.
Abrasive type
There are five main types of sandpaper to choose from, but not all of them are good for woodworking. Cellophane, also known as flint paper, is lightweight and usually yellowish. Cellophane breaks down easily and is rarely used in woodworking.
Garnet paper is usually brownish-red and is commonly used in woodworking. It won't sand the wood as quickly as other sandpapers, but it will leave a better finish. Garnet is the best choice for finishing the grinding.
Alumina is another common type of sandpaper used for woodworking projects. It is the type of paper most commonly used in electric sanders. Alumina is more durable than garnet paper, but will not leave a great finish.
Silicon carbide paper is usually dark gray or even black. This type of paper is mainly used for finishing metals or for "wet grinding", using water as a lubricant. Although some advanced surface treatments use silicon carbide paper, it is not usually used for woodworking.
Finally, ceramic sandpaper is made from some of the most durable abrasives and can remove large amounts of rough material in a short amount of time. Ceramic paper is usually used for belt sander belts, but is sometimes used for hand sanding of wood. It usually leaves a very rough surface, so be careful when using ceramic sandpaper, especially on plywood or lacquer, which can quickly go through the finish layer and destroy the work itself.
At this point, the introduction of sandpaper is the end. In most general woodworking applications, you may find that the sanding step uses a different sandpaper starting with the initial coarsely sanded alumina paper, followed by a more fine garnet paper leaving a very smooth surface, which is also an aspect that shows your woodworking skills. Once you've finished polishing, you can start dyeing or painting your woodwork. Now that you've seen so much, start creating your own woodwork.
