Sanding paper is most demanded in those cases when there is work with wood material. Since wood has a rough surface, for its removal, craftsmen almost always use just such a thing as emery. What is it? Sandpaper or sandpaper is an abrasive material, the main purpose of which is to give perfect smoothness to almost any surface.
Paper backed emery
There are a lot of types of sanding paper . However, only a few of them were most widely used. The most used were emery on a paper or fabric basis.
If we talk about the paper basis of this thing, then it is most often characterized by a rather high density of material. This is a very important parameter, since it will determine what mechanical damage the paper can withstand. In order to increase the service life and range of use, sanding paper can sometimes be made on a waterproof basis.
The advantages of this type of material:
- low cost of material, especially when compared with additional grinding nozzles, which are sold on a drill;
- using this type of sandpaper, you don’t have to worry that during the work the base will lengthen;
- On the surface of sanding paper with a paper base, it is possible to spray with the least abrasiveness during its production.
However, there are also disadvantages, which include weak wear resistance, as well as the low strength characteristic of paper.
Fabric base
For the production of sanding paper with such a base, cotton is most often used, which is pre-treated with a special resin. It is because of this production method that fabric emery is characterized by increased resistance to water, improved flexibility, and is also characterized by a fairly high strength.
The disadvantages of such a grinding skin include the fact that cotton tends to lengthen during operation. The second drawback is the higher cost in comparison with other bases, since cotton itself is more expensive, in addition, a special resin is needed for production.
It is worth adding that in specialized stores are currently selling combined grinding skins. Such emery is based on paper and fabric materials glued together.
Types of emery by the method of applying grain
Emery paper differs among themselves not only in the base, but also in the type of grinding grain that was used to create it.
- The first type is paper that has an open layer. During the production of this type of paper, grain is sprayed in such a way as to cover up to 60% of the total area of the skin. The advantages of this class include the fact that during operation it will not become clogged with garbage due to the presence of large gaps between the grains of the abrasive. Most often, this type of emery is used for processing wood coatings or surfaces with medium density.
- The second type is a closed filling. This type of paper assumes that the entire base of the skin is covered with a dense layer of grain during production. The use of this class of emery is excellent for processing hard surfaces, but it must be used carefully, as it clogs very quickly.
Abrasive Grain
Today, different abrasive grains are used to produce such paper or nozzles for a drill. On this basis, 4 different types of material can be distinguished:
- Ceramic abrasive . This type of abrasive is one of the hardest, and therefore it is used for rough processing of wood material. It is produced in the form of special tapes.
- Silicon carbide . This type of grain is characterized by low strength indicators, as well as medium resistance to wear. The scope of this material is grinding of body metal, fiberglass, etc.
- Alumina . This type is very fragile, since it breaks very quickly when subjected to mechanical stress. However, this drawback can also serve as an advantage, since in case of breakage new faces will be formed for grinding, which means emery can be used much longer.
- Pomegranate Most often, paper with such an abrasive element is used to process different types of wood. This type of abrasive is considered one of the softest, and therefore its resistance to wear is very small. In order to work with it, you need to have a lot of patience, since the process of sanding with such paper is very time-consuming.
Sanding paper marking
The designation of the grinding skins is regulated by GOST. In this document, the grain size is indicated as the main parameter, which is indicated by the letter P, and the limits of this parameter are numbers from 12 to 2500. It is important to understand that the larger the specified number, the smaller the grain size on paper. It is also worth noting that in some former Soviet republics the USSR GOST is used. In this case, the marking will indicate the number 20-N. In this case, it is important to know that tens of microns of grinding are indicated. If you need to specify a simple number of microns, then the marking will look something like this: M20. An approximate classification of the types of sandpaper looks like this:
- for the most rough processing of the material, emery of the type P22, P24, P36 80-N, 63-N, 50-N is used;
- for simply rough surface treatment, grinding with the marking P40, P46, P60 40-N, 32-N, 25-N is used;
- in order to carry out primary grinding of the desired surface, paper grade P80, P90, P100, P120 20-N, 16-N, 12-N, 10-N is used;
- In order to complete the grinding of the material and give it perfect smoothness, it is necessary to use an emery cloth of grade P150, P180 8-N, 6-N.
Sanding paper size
The sizes of the sandpaper are determined depending on its grain size. Emery with a grain index of 50, has a width of 720, 750, 800, 850, 900, 1000. This indicator is measured in millimeters. Paper with such width and grain parameters is available in rolls of 30 meters in length. It is worth noting that with P50 and a width of 1250 mm, the length of the roll is reduced to 20 meters. For sanding paper, GOST 6456-82 defines all typical sizes, production and acceptance rules.
Production
The production technology of this product is the method of applying abrasive to the base. There are several methods for performing this operation. This may be a mechanical application method or an alternative using an electric field. Each manufacturer of sanding paper chooses which method to apply abrasive. It is also worth noting that the choice of binders will also be an important factor in the production. They can be of various brands or types. Also, the strength and mode of operation of the grinding skins will depend on the type of ligament.