Tips for using sandpaper
1. Polishing
It means that you are satisfied with the appearance and hope to remove the traces of processing and make the surface smoother.
2. Don't skip numbers
When sanding, sandpaper should be used from coarse to fine, and try not to skip numbers. That is to say, for example, if you start with No. 120, then 180, then 240, and so on. If you don't have so many numbers of sandpaper, at least make sure that the next number is within one times, such as 120 to 240 to 400, and so on. This seems to require a lot of sandpaper and is very expensive, but if you look at it, you will know that in fact, in addition to the large consumption of coarse sandpaper, the consumption of fine sandpaper is very limited, which should only account for about 1/10 of the coarse sandpaper. Depending on the hardness of the wood and the thickness of the wood grain, the number of the coarsest sandpaper for sanding is also different. Generally speaking, soft wood or wood with a rough surface starts with No. 100, and if it is a more delicate or smooth wood, you can start with No. 240.
3. Eliminate the scratches of the previous sandpaper
If you follow the principle in the previous article and do not skip sandpapers, then the task of each sandpaper is to eliminate the scratches left by the previous sandpaper. Generally speaking, this can be done in 5 to 10 strokes. In this way, fine sandpaper should be very economical, and coarse sandpaper is more consumed because it also has the task of shaping.
4. How fine is fine enough
This question depends entirely on the nature of the wood and the effect you want to achieve. Although the requirements for the results vary from person to person, the general theory is that the coarser the wood grain, the coarser the sandpaper. If the scratches produced by the finer sandpaper are completely covered by the wood grain itself, there is no need to continue sanding. For me, I only use 240 for walnut, ash, oak and the like. For cherry, maple and the like, I will go up to 400, and for sandalwood and the like, I will go up to 800.
5. Sanding between coats of paint
There will be some burrs between the paints, and you can use 400 to lightly sand. The purpose here is to remove the burrs, but you don't want to destroy the paint film that has been applied previously. Some people also recommend this thin wire ring or this 3M sanding cloth, the principle is the same.
6. Grinding media
Grinding media should be considered consumables. The most common wood sandpaper is generally made of silicon carbide. The main difference lies in the material of the carrier. There are two types of wear and tear on sandpaper. One is that the silicon carbide falls off the carrier, and the other is that the carrier breaks. Silicon carbide itself is very hard and can be considered as not wearable. Ordinary sandpaper is made of paper material and is relatively fragile. Sandpaper used on machines, such as belt sanders, is made of cloth and is much more durable. I suggest that whether you use a machine or manual sanding, you should choose cloth sandpaper for machine use. For manual sanding, you can make some auxiliary tools yourself.
