Sandpaper on a fabric basis marking. Sandpaper base materials. Types of sandpaper depending on the composition

What sandpaper to choose? It depends on what kind of work you are going to do - primary rough processing, surface leveling, grinding or polishing. To quickly make a choice, see the table:

The main characteristic of "sandpaper" is graininess. The most common grain size standard is FEPA (Europe, India, Turkey, South Africa), also known as ISO 6344. This standard for the most part corresponds to the current Russian standard GOST R 52381-2005 and is marked with the letter P and numbers from 22 to 2500. Than more number on the marking, the finer the particle size of the abrasive.

At the same time, there are also earlier GOSTs, even those that existed in the USSR, for example, 20-N or M5 / N-00 “null” - the finest sandpaper.

In addition, there are ANSI (CAMI / UAMA) and "0" grade (USA, Canada), JIS (Japan), GB (China) standards.

An equally important parameter of sanding paper (or fabric-based) is the material of the abrasive.

Currently used abrasives:

silicon carbide (carborundum);
ceramics;
pomegranate;
aluminum oxide (electrocorundum);
synthetic diamond.

Electrocorundum is the most widely used abrasive. Sandpaper with this coating is the strongest and most durable. Additional strength and an increase in the abrasive abilities of electrocorundum are given by the addition of chromium oxide in the manufacture of such a “sandpaper”. It is easily distinguished by its ruby ​​color.

Sandpaper with carborundum. Most suitable for processing plastic, glass, fine grinding for metal.

Garnet coated paper. Wears out faster due to the fact that garnet is a relatively soft mineral. Therefore, it is used for grinding more soft materials, for example, a tree. Leaves behind more smooth surface.

Grinding paper is also distinguished by the type of abrasive application (filling).

Open (or semi-open) coating - the abrasive covers 40-60% of the base surface. This type of backfill eliminates the formation of lumps on the abrasive surface. Suitable for processing loose materials: putty surfaces, wood.

Closed coated (or solid) - suitable for sanding hard materials: hardwood, metal.

Flexible abrasive material based on the actual paper or fabric on which the abrasive is glued in the form of a grain. Grain happens different sizes this determines the main characteristics of the material, which are reflected in the marking.

The first in the marking in the new GOST is the letter "P", the number behind it indicates the grain size. The larger the number, the smaller the grain. Let's take a closer look.

• For very rough draft work, sandpaper marked P22 is used; P24; P36;
• For rough grinding, take P40; P46, P60;
• During the initial stripping, P80-P120 is used, and the final P150; P180;
• In the production of grinding hard wood, sandpaper P280 is taken; P240;
• Before painting, take P600 for polishing; P400;
• Plastic and ceramics are treated with P1000 sandpaper;
• For final polishing take P1200; R1500.

Most often, paper is taken as the basis, the disadvantage of which is the wear rate. The advantage is its low cost and ability to withstand a large number of loads.

Also not uncommon is sandpaper on a fabric basis. It is considered to be more durable. Also, fabric-based make waterproof sandpaper options.

Sandpaper on a combined basis: paper plus fabric is needed when you need to combine wear resistance with high pressing force.

Type of abrasive

Electrocorundum. Rigid type of abrasive, has excellent cutting ability, resistant to pressure. Swimming trunks are made in the charge.

Silicon carbide. Consists of sharp and brittle particles that crumble under pressure and are divided into smaller ones. Suitable for glass grinding, finishing metalworking. Made from an alloy of krenezem and graphite.

Pomegranate. Very brittle abrasive. Used for sanding wood. The output allows you to get a perfectly smooth surface. Abrasive of natural origin.

It is customary to divide sandpaper by grit.

Grit refers to the number of grains of abrasive per inch2.

Coarse-grained from 12 to 80 numbers, it is a rough and coarse abrasive. It is used for rough work for shaping, removing the top layer of paint. Leaves behind deep furrows and requires further processing.

Medium grit from 80 to 160, medium abrasive. Used at intermediate stages to smooth surfaces after rough processing, or when it is necessary to remove a small layer of paint or varnish. It also leaves behind shallow furrows.

Fine-grained from 160 to 4000 numbers, fine abrasive. Used for finishing work in the final processing of products.

Sandpaper is produced various shapes. Two types can be distinguished in particular: This is sandpaper in rolls and sheets.

Rolled sandpaper is produced on different bases with different grain sizes.

However, there are many more forms:

Fiber sandpaper is a mesh nonwoven fabric impregnated with abrasive is very flexible in its structure. It is used for matting products in preparation for priming and painting.

Abrasive mesh is a polyester mesh coated with abrasive.

Used for grinding and matting various materials, however, it is most applicable for grinding after puttying due to the mesh structure, dust does not clog the base, which significantly saves material.

Striped sandpaper has good cutting ability and long term services. Also has openings for removal of dust.

Foam sandpaper is used for processing painted and varnished coatings, most often used for processing corrugated surfaces.

Waterproof sandpaper is also produced.

A lot of sandpaper is also produced for various equipment, this is both a gluing base and tape.

Sanding flowers are used to eliminate small defects. Flower shape to avoid streaks.

Sanding belts are loaded into various sanding machines.

The scope of sandpaper is very large; it is used in construction and finishing when tearing out surfaces after puttying. In woodworking when grinding wooden surfaces. Metalworking and mechanical engineering when cleaning before painting, matting surfaces.

This list of directions goes on and on for the use of sandpaper.

Sandpaper marked "L1" is used for sanding soft materials. Sandpaper marked "L2" is used for grinding metals. Sandpaper marked "M" denotes its moisture resistance intended for wet processing, its advantage lies in the fact that during processing there is no dust and the surface becomes smoother. Sandpaper marked "P" is not intended for wet processing.

Sandpaper is the most popular abrasive, for which there is no alternative yet.

A locksmith, artist, sculptor, finisher, furniture maker cannot do without it.

This simple tool is in every car body repair shop, every home, a good owner.

Emery is needed for processing different surfaces, metal, wood. The use of sanding paper directly depends on its specifications, backing material, abrasive type and grit.

What is granularity

The abrasive element is applied to the base, paper, fabric, etc. The ratio of the amount of applied abrasive material (grains, powder) to the square of the surface is called the paper grain.

Less graininess or a smaller number of grains on the surface of a unit area - the paper is rougher, tougher. Small grains make the paper softer, more of them are placed on the same square of the area - the grain number is higher.

It is important to know: the more abrasive is required to cover a unit area, the smaller its crystal. The less abrasive falls on the surface of a unit area, the larger it is.

Primary wood processing

The purpose of paper for certain works directly depends on its grain size, which is main characteristic, an indicator that determines the scope of application:

1. Primary or rough surface treatment, removal of paint and varnish coatings, corrosion and rust require coarse paper, grit 12 and 80.
2. Elimination of damage after primary processing, scratches visible to the eye flaws, surface leveling, bumps, irregularities, requires indicators of 80-160.
3. Grinding leveling of irregularities of medium size, grit P80-P120 is used.
4. Finishing surfaces, smoothing spots - grit 160-1400.

A characteristic of grit is its grit, this is a characteristic of the density of a stone or other substance used for abrasive. High grit allows the use of a flexible abrasive material for processing hard wear-resistant surfaces.

Note: it is necessary to take into account the grit content of the abrasive to achieve the desired results of surface treatment!

Types of flexible abrasive are also distinguished by other indicators, but it is already clear that the graininess indicator is the basis of marking.

Gradation of abrasive depending on the material

Types of sandpaper

Abrasive material is produced from organic rocks and chemical compounds. The gradation of the abrasive is made in accordance with the properties that the original material has, these are:

• granite, effective on any surface, traditionally used when working with hardwood;
• silicon carbide, in demand for working with metal, plastic, fiberglass;
• ceramics of high hardness, strength, mainly used for tapes grinding machines;
• aluminum oxide, valued for long terms use, it is applied at delicate processing of surfaces.

The original material of the abrasive is reflected in the marking of the skins. When choosing a skin for work, carefully study wrong side to get acquainted with all the technical and operational characteristics of the tool.

Marking

The variety of sandpaper today is classified in two standards. The marking is made in accordance with the FEPA standard, as well as the ISO 6344 standard.

The norms of both correspond to the Russian GOST, which in turn is recognized by the world community. In some countries, abrasive paper is marked and produced in a special way.

Traditionally, the skin is produced in the form of sheets, has the name sheet, rolls, has the usual markings. Marking "P" - designation of grain size. The numbers following the letter indicate the range 12 -2500.

Take note: the higher the grain number, the finer the grains.

GOST of the Soviet Union denoted the value of the main indicator in microns. Since then, the classification has been preserved, which is sometimes used in neighboring countries, former republics, and in the storerooms of some zealous owners - M20, M 7, "null".

Skin for preliminary work:

1. The roughest, primary work with the surface is carried out using skins, on which a large fraction of the abrasive:

• 80-H;
• 63-H;
• 50-H;

1. Subsequent processing is carried out with emery:

• 40-H;
• 32-H;

1. Initial sanding requires the use of paper:

• P100;
• P120;
• 20-H;
• 16-H;
• 10-H;

1. The final stage of grinding is done with sandpaper:

• P150;
• P180;

The phased use of abrasive material allows you to carefully select all the existing flaws, level the surface, prepare it for finishing, which is carried out in the same way in several steps.

Sandpaper P240

The classification of fine-grained sandpaper implies the use of a tool for durable wood (oak, ash):

1. primary grinding:

• P240;
• 5 -H;

1. polishing before applying stain, primer, paint:

• P400;
• P600;
• R800 ;

Sandpaper P1200

The use of fine-grained skin for metal, ceramics:

1. grinding:

• P1000;

1. polishing:

• P1200;
• P1500;
• P2000;
• P2500 H-0;
• H-01.

The letter "P" means classification according to ISO 6344, the letters "H", "M" correspond to our domestic marking. Numerical values ​​indicate the size of the abrasive fraction.

For example, the value of P80 says that the marking complies with the international standard, the abrasive is passed through molds measuring 80 per inch. It is not difficult for the buyer to figure out what kind of work this or that tool needs to be done. The wrong side will help you choose the right sandpaper for its intended purpose.

What is written on the back

Wrong side of sandpaper

All information about grain size, base and other data included in the product labeling is printed on its back side.

On the inside, the buyer will receive information about the base, its type, manufacturing technology. It also contains information about the type of abrasive material.

For example, significant designations of characteristics:

• "L" - means that the paper is sheet, roll is not indicated in any way;
• "L1", "L2", "M" - that the paper is waterproof;
• "P" - that is afraid of moisture, absorbs it like a sponge and collapses;
• "1" - grinding of soft surfaces;
• "2" - grinding of hard surfaces.

There are other designations intended for specialists.

Classification by base material

The base, sandpaper substrate is another equally important characteristic, which also determines the purpose of the skin. Substrates are three types. The decision which one to give preference to depends on the intended use of the abrasive:

• paper base, which is mainly produced with a fine or medium-sized grain fraction, is the cheapest, among the disadvantages is a short service life, moisture absorption;
• fabric, which has high wear resistance, strength, elasticity, moisture resistance;
• combined, high grit, high elasticity, strength, wear resistance.

Modern industry produces abrasives based on fiber and polyester. The processing of plastic wood and other fibrous materials allows the use of paper coated with abrasive grains of 60% of the area.

Modern backing materials allow for the most efficient use of the granular tool. For metal processing, a coating of 100% of the tool area is made. The elasticity of the base is necessary when treating surfaces from rust and paint.

grinders use a water-repellent base due to the use of cooling and lubricating fluids.

In production, in workshops, at home, a stock of tools will not interfere, so that the always worn out used emery can be replaced without interrupting work. Emery skins, tapes are inexpensive, always available in a full range.

Do right choice, pictures of the types of sandpaper will help to understand the issue. Interesting Facts about sandpaper, see the following video:

Sandpaper is very often used in the repair and decoration of premises, and it is used both manually and with the help of various power tools. It seems to be such a simple material, but many do not know the classification of sandpaper grit and very often they get confused in the store, not knowing what kind of sandpaper they bought before, it was small or large. In this article, we will analyze the classification of sandpaper according to the “fineness” of the grain and the types of work that can be done with coarse or fine sandpaper.

So that you don’t have any questions - which sandpaper to sand the tree for painting, which one is better to peel off the old varnish, and which one to sand the windows from the old paint. Now, knowing the classification of paper, its graininess, you will correctly select a large or small “skin” for your work.

• Sandpaper is domestic (Belgorod) and imported, respectively, and the classification according to the graininess of the sandpaper is different. Domestic comes with the marking H, for example, 8-H sandpaper is small, imported with the marking P, the numbers are large, for example, P100. Note that sandpaper in products is most often imported, but domestic - in large rolls 900 mm high, it is sold by running meters.

• Therefore, if you decide to skin the tree by hand using special skin holders, then it is better to buy domestic rolled sandpaper. Price running meter depends on the grain size of the sandpaper, for example, 1 meter of 16-H costs 180 rubles, 40-H already costs 200 rubles. The larger the sandpaper, the more expensive it is.

• Note that most often the paper is waterproof, which allows you to process the surface even with the addition of water (for example, polishing marble with water). Well, one more feature of the “skin” is that it is better to buy on a fabric basis, it will last noticeably longer than on paper.

This is how rolls with a volume of 30 linear meters look like:

Of course, in stores they can cut off half a meter for you and it will be inexpensive for you and enough for work and even still left.

Also popular products from domestic sandpaper are petal grinding wheels for machine tools (dimensions: diameter 150 mm, fit 32 mm, width 30 mm or 50 mm). Everything else is overwhelmingly imported.

This table shows the correspondence between the grains of sandpaper, domestic and imported, at the top - the smallest, at the bottom - the largest.

Grit table (marking) of sandpaper.

M40(zero) P400
4-H P320
5-H P220
6-H P180
8-H P150
10-H P120
12H P100
16H P80
25-H P60
32-H P50
40-H P40
50-H P36
80-H P24

Of course, most often in stores you can see imported sandpaper marked P. Most often, finishers do not buy roll paper, but products from it, for example, an endless belt (for a belt sander) or round discs Velcro (for eccentric sander or angle grinder). All kinds of this sandpaper come with import classification. Most often bought grains:

P40 - coarse grain
It is used for the initial processing of wood, for example, for stripping a thick layer of varnish or paint. The grain of the sandpaper is large, so it does not clog immediately, which allows you to do a large amount of work.

P60 paper a little smaller, but you can't call it small.
It is used as an alternative to P40, if suddenly p40 is not on sale, the types of work are the same.

P80 noticeably smaller

It is used for subsequent processing of wood after the passage of coarse sandpaper. If you are sanding wood for painting or varnishing, you can use P80 paper. Of course, it is better to use even finer sandpaper, such as P100 or even P120.

P100-P120

Fine sandpaper, used for final processing wood for painting, staining or varnishing. due to the very fine grain, it clogs very quickly, so the consumption of fine skins is always high.

Ideally, if you want to have a smooth wooden surface, it is better to go through three types of sandpaper, but you yourself understand that this is quite expensive, so in most cases the tree is prepared for painting with two types of sandpaper, most often it is P60 and P100.

The history of the emergence of sandpaper is lost for centuries. Back in the 13th century, people used sanding paper hand made. China has traditionally been a pioneer. A thin layer of sand mixed with ground sea shells was applied to sheets of parchment using organic glue. The device was used to process wooden products, and parts made of bronze and gold.

Modern sandpaper (popularly called sandpaper, comes from the tradition of using shark skins as a grinding device) is still made by applying a thin abrasive layer to flat surface, however, the quality of workmanship has stepped far ahead.

Fabric-based sandpaper appeared, modern sandpaper is used not only for manual processing, but also with the help of machines.

The product range is so wide that an inexperienced buyer can simply get lost when choosing. We will help you navigate the variety of sandpaper, and tell you about the features of its use.

Types of sandpaper and manufacturing technology

Since the subject of consideration is a flexible base with an abrasive powder applied to it, the classification will be in these categories:

The basis

paper base

The most common cellulose products are used, without the addition of chemical components. An adhesive base acts as some kind of reinforcement, holding the abrasive.

It wears out quickly, so the main scope is manual processing. Can be fixed in simple fixtures. For example - for grinding walls after plastering.

The main advantage of the material is accessibility.

Fabric base

The logical development of a material handling fixture. Wear resistance is an order of magnitude higher, though the cost has increased. It is used under heavy loads, mainly on grinding machines and manual machines. The high tensile strength allows the sandpaper to be used as a continuous band.

Cut into thin strips, the cloth-based sandpaper becomes a tool for fine work on small items.

IMPORTANT! The adhesive composition for the fabric base must be elastic. If you are offered such sandpaper with hard glue, it is a fake.

Waterproof sandpaper is produced on this basis.

Combined base

A trade-off between the cheapness of paper and the strength of woven material.

It can be used in sanders (with the exception of the continuous belt) and for heavy hand work. Often such paper is used in inexpensive petal paper, along with fabric.

When wet, it quickly loses strength.

Velcro

Self-adhesive sandpaper does not actually have a sticky layer. It works on the principle of similar Velcro on clothes. The sandpaper holder is made in the form of small hooks, and the fabric base of the sandpaper has a velvety layer of many threads. Velcro sanders allow you to change worn paper in one motion, saving time.

abrasive material

As we have already said, the skin consists of a base, and an abrasive powder applied with glue.

If earlier crushed glass, sea sand or grated mollusk shells were used for manufacturing, today abrasives are carefully selected for various conditions applications.

ceramic chips

Of course, this material has nothing to do with broken tiles. This is a specially made and annealed fraction, which is distinguished by its special hardness. It is used for rough processing and giving the initial shape to the workpiece. When applied to fabric, it comes in the form of continuous belts for grinding machines. It quickly loses the working layer, but the efficiency is very high.

Silicon carbide

A material well known to whetstone users. Relatively versatile abrasive. Excellent for processing plastic and metal. Coarse grit makes it possible to remove paint from old surfaces, and a fine fraction produces final grinding. Zeroing from such a material actually polishes the workpiece.

Favorite sandpaper in yacht yards - works well on fiberglass.

Electrocorundum

Not as hard as the previous material - but more resistant to breaking. Versatile in terms of application.

Pomegranate

Not the gem that adorns royal crown, but a stone from this family. It has a natural origin, so it is not so expensive. It has unique properties - when processing wooden blanks, it creates an ideal surface for varnishing. Therefore, pomegranate skin is valued by joiners and carpenters.

Alumina

A material with conflicting properties. Fragile and strong at the same time. With intensive work, it crumbles, exposing fresh sharp chips. At the same time, the sandpaper seems to be updated without losing its abrasive properties. Works well on hard metals. However, his element is the primary processing of wooden blanks.

Consumer properties of sandpaper

Many mistakenly think that there are two types of sandpaper: sheet and roll. Such gradation exists, but the diversity does not end there. Sandpaper marking tables offer hundreds of designs.