Cutting wheels for grinders for metal: dimensions of thickness and diameter

Types of cutting discs

metal disc from Vulcan

Among the many consumables for grinders, the most common are metal cutting discs. They are somewhat cheaper than their stone or concrete counterparts and are usually painted blue. The difference lies in the type of abrasive material: coarse chips or crushed diamond. To polish metal, special nozzles coated with fabric are used.

Consumables vary in size, thickness, coding and price. All this data is indicated on the front surface of the cutting disc.

Marking

The choice of the right tool is facilitated by the presence of markings. It contains the technical parameters of consumables in encrypted form. For example, this is what an alphanumeric set of markings for a cutting disc looks like, produced by a Russian manufacturer:

1. — The image shows the tool manufacturer — Luga Abrasive Plant (Luga, Leningrad Region).
2. — Tool name:
   cutting wheel - in Russian;
3. cut –off – wheel – in English translation.
4. — Purpose: for processing steel (inscriptions “steel”, “steel” on the circle).
5. — The dimensions of the circle are indicated (outer diameter x thickness x bore diameter):
   in mm – 200 x 2.5 x 22.23;
6. in inches – 8”x 1/10”x 7/8”;
7. digital designation "41". This is a characteristic of the design of the circle - here it is flat.
8. — The circle is designed for 7650 rpm, while the maximum peripheral speed should not exceed 80 m/s.
9. — Technical parameters of the wheel material are determined from the designation “A 30 S BF”, where:
   A – means that the abrasive is based on white electrocorundum, which is specifically used for metal processing;
10. 30 – abrasive grain size, here it is average;
11. S – hardness of the circle, here the circle is hard;
12. BF - denotes the type of bond, here synthetic resins with glass fiber reinforcement.
13. — Rules for safe work in the form of signs indicating the required action.
14. - GOST 21963 - 2002, GOST R 52588 - 2011, EN 12413 - Russian and European regulatory documents to which this tool complies.

The marking of a foreign manufacturer of tools for angle grinders is as follows:

1. — Tools under the NORTON VULKAN brand are produced by the Saint Gobain corporation, headquartered in France.
2. —The purpose of the cutting disc (the company produces only such a tool for angle grinders) for processing steel (in addition, for visualization purposes, the label for wheels intended for metal processing is blue) is duplicated in several languages.
3. — The circle is designed for 12250 rpm with a maximum peripheral speed of 80 m/s.
4. — The dimensions are the same as on the Russian disk - in mm and inches.
5. — The digital designation “41” has been added to the technical parameters of “A60S – BF41”. This is a characteristic of the design of the circle - here it is flat.
6. — Methods of safe work must be indicated.
7. — The regulatory documents to which the instrument complies are issued by the European Union.

Selection by size

The outer and inner diameters of the circle are indicated on the main surface of the consumable. There are 9 standard external sizes from 125 to 500. The indicator is selected taking into account the class of the angle grinder. It is strictly forbidden to work with a larger circle. Only for large professional tools can you purchase consumables of any diameter.

The inner or bore diameter must match the size of the drive shaft. Most shafts are produced with a diameter of 22 mm, so 22.2 mm is an almost universal mounting diameter. Both sizes must fit the instrument model!

Classification by material

Metal discs for an angle grinder are made from several types of materials:

1. Diamond.
2. Carbide.
3. Abrasive.
4. From metal wire

Abrasive

The base of the abrasive wheel consists of fiber or thick waterproof latex paper. Between the layers of paper there is a reinforcing mesh. A layer of abrasive material is applied to the base - particles of zirconate or aluminum oxide, tungsten carbide, ceramic grain or corundum. The binding component for the abrasive is a resin or polymer. Cutting wheels for grinders and grinding discs are made from this material.

The advantage of an abrasive grinding or cutting disc is the most affordable price. Disadvantages - rapid wear, emission of sparks during operation. Cutting metal with an abrasive wheel produces an unpleasant odor.

A metal cutting disc can be made of paper with a reinforcing mesh. Fiber discs are used only for grinding and polishing, always with a support plate made of plastic or rubber. It serves as a stop and cools the abrasive. The fiber wheel is ideal for rough removal of old paint. Abrasive ones include sanding flap attachments designed for processing welds.

Diamond

Diamond blades for cutting metal are made of steel. Diamond coating is applied to the cutting edge. This type of wheel cuts and grinds any metal. Advantages: no sparks or odor, long service life. Disadvantages - high price and the need to take frequent breaks (the diamond cutting wheel is afraid of overheating).

Carbide

Carbide - instead of diamond coating, they have solder on the edges made of high-carbon molybdenum steels with additions of chromium and nickel. There are carbide discs for sale for special purposes: for thin, high-carbon, stainless steel, aluminum.

From metal wire

Disc brushes are made from twisted steel wire. They are intended for rough cleaning work: removing rust, scale, old paint, other types of persistent plaque, burrs, and processing seams. There are two types of brushes in shape: ring (solid circle), bundle (made of twisted bundles of wire).

Fabric, fur

To polish metal with a grinder, various attachments are used: felt, felt, fur (sheep's wool), foam rubber. They can be used in combination with polishing paste. A support plate made of plastic or rubber is installed under the nozzle on the angle grinder, to which a polishing disc is attached with Velcro.

When cutting or processing metal, you cannot use discs for stone, concrete, or wood for angle grinders.

Selection by thickness

It's much easier to cut with a thin circle. Indeed, when cutting into metal, a thick cutting disc experiences powerful resistance; more effort will be required to overcome it.

The cut with a thin disk is more accurate, and the work goes faster. The working surface heats up less, so it lasts longer. Thin circles are considered to be up to 1.2 mm thick, compared to the standard 2.4-2.5 mm with a diameter of 125 mm. The thickness of the disc is directly proportional to the diameter!

This option is suitable for small grinders with batteries or low power, allowing you to save energy.

There is an opinion: the thinner the consumable, the more fragile it is. This is nothing more than a myth. Any cutting disc is reinforced from the inside with non-woven fabric, so the safety of work depends on compliance with the rules, and not on the thickness of the consumable.

Classification by type of work

Types of metal processing with a grinder:

• removing the old layer of paint, including from metal surfaces;
• removal of rust, scale, dirt;
• cutting;
• processing of welds;
• grinding and polishing.

Metal circles for angle grinders are:

1. Cut-off. They are designed for making cuts. Cutting discs for grinders for metal have a solid or segmented cutting edge. They are made from several types of materials. The difference is in service life, price, operating features. The thickness of the cutting wheel also plays a significant role. The thickness of the cuts and the durability of the nozzle depend on it.
2. Roughing (grinding) - for grinding and removing old layers of paint, varnish, etc. from the metal surface. A variety of roughing discs - flap: end-face, batch, with a mandrel. They are used in metal processing, cleaning welds and burrs, removing rust, etc. The end wheel is suitable for angled and regular flat processing. The batch disk is used when working over a large area. Wheels with a mandrel are used when working with cavities. The flap disc is smoother than a regular sanding disc.
3. Cleaners – for removing rust and stubborn dirt. These include disc brushes made of rigid metal wire.
4. Polishing – for final polishing of surfaces. These include polishing replaceable fabric, foam and fur attachments. Metal polishing can only be done using an angle grinder with speed control.

It is forbidden to use wheels for purposes other than their intended purpose (for example, a cutting disc for an angle grinder instead of a grinding disc).

Encoding

The circle specification is encoded in four characters, Latin letters and numbers:

• the first letter indicates the material of the abrasive chips: AS - white electrocorundum, it is suitable for working on stainless steel, because the alloy contains practically no chlorine, sulfur and iron, which increase the cutting temperature; A - electrocorundum; C - silicon carbide - such circles are used to cut tiles and stone, but not metal;
• number - indicates the number of abrasive grains per unit area. The higher the number, the smaller the particle size. For cutting steel, larger grains are used - 24, 30; for working on soft non-ferrous metals, smaller ones - 60 or 40;
• the Latin letter is the hardness of the ligament. The first letters of the alphabet are the softest letters, the further from the beginning the harder. The softest bonds are selected for processing the hardest metals! You need to know this important ratio when choosing consumables for an angle grinder. During cutting, worn particles fall off and new ones, not yet dulled, come into play. If the bond is too tight, the cutting disc becomes “greasy”: it heats the metal and makes cutting difficult. At the same time, a circle with an overly soft bond wears down faster;
• the last Latin letter (or pair) is the name of the binding material, most often bakelite. Denoted as BF.

How to replace

The grinder disc is a consumable item. Therefore, it has to be changed frequently. There is a simple algorithm in which an important role is played by the original design of the key supplied to the consumer along with the grinder.

1. — The protruding rods of a special key are installed in the grooves of the fastening nut.
2. — At the same time, press the lock button located on the gearbox housing. It will lock the rotor from turning.
3. — Turn the key counterclockwise to release the fasteners of the worn disk.
4. — The old disk is replaced with a new one of the same technical characteristics and size. The new disk is installed with the markings facing out to remind you of the disk parameters and for other good reasons (see explanation in the video above).
5. — The fastening nut is first tightened by hand and finally tightened with a special wrench.

The Bulgarian is ready to continue fulfilling its functional purpose.

Price and manufacturers

metal disc from Hitachi

For rare household jobs, cutting discs from the low price category are quite suitable: “Sparta”, “Zubr”, “Tsentroinstrument”. With occasional use they will last quite a long time.

The quality of the abrasive material is not bad, the price is reasonable. The main thing when working with consumables of this class is not to work for a long time without breaks. If the circle stops sawing, it is cleaned with red or yellow brick.

Professional metal discs cost 3 times more. But only they are suitable for industrial use. These are consumables, “Distar”, “Hitachi”. They withstand daily work with the most difficult materials. Professional circles, as a rule, are intended to work with a specific material: reinforced concrete, granite, tiles, steel, non-ferrous metals.

Video with a metal cutting disc test:

How to choose the right disc for an angle grinder

Wheels for grinders can be purchased in retail chains in a varied assortment and at reasonable and high prices. With the help of products made from different materials and using different technologies, diverse operations are performed. What are the basic selection rules and what to pay attention to? It is necessary to clearly know what materials you will be working with. You also need to pay attention to the following factors:

• diameter and thickness (indicators should not be greater than indicated in the passport data for the angle grinder or, more simply, the disc must fit into the protective casing);
• seat size (must correspond to the diameter of the grinder spindle);
• rotation speed (it must correspond to the type of grinder, indicated on the disk itself);
• type of cutting (dry, wet or combined).

The rules that must be followed to make products last longer are simple. For hard materials, choose discs with a soft binding, for soft ones – with a hard one. The work area should not overheat during operations. Therefore, it is recommended to periodically remove the disc from the material to allow it to cool. You cannot make deep cuts in one pass. Do not press the product with great force and work at high speeds. Remember: if during operation the disc experiences beating or cracks appear on it, you cannot cut with this consumable. It needs to be replaced.

The video explains in detail and clearly about grinder wheels:

We ask those who have encountered discs for grinders, made their choice and worked with specific models, to share their experience in the comments to the text.

Review and comparison of cutting wheels

LUGA-ABRAZIV

CRATON

ATTACK

DEWALT

BOSCH

STOMER

Rating of quality products from 10 rubles

Metabo, 125*1*22 mm

The cutting attachment is produced in the Celestial Empire. Stainless steel is used in production. Will handle high-alloy steels: acid-resistant, heat-resistant and stainless steel. Bore diameter – 22.2 mm, outer diameter – 125 mm. To prevent the circle from splitting or scattering during operation, the manufacturer uses a special bakelite bond in the manufacture of products, which reduces the possibility of injury to nothing. When choosing a product, you need to pay special attention to the speed of rotation to prevent destruction of the disk. The maximum rotation speed is 12250 rpm. Type – abrasive, shape – straight. The reviews are only positive.

You can purchase the product for 50 rubles.

Metabo cutting wheel, 125*1*22 mm

Advantages:

• reliability;
• wear resistance;
• practicality;
• long service life;
• safety.

Flaws:

• not identified.

Dexter, 125*1*22 mm

The product from the Polish manufacturer is very popular among domestic craftsmen. Available in stainless steel. Suitable for working with high-alloy heat-resistant, acid-resistant steels and stainless steel. Suitable for all modern angle grinders. The maximum permissible rotation speed is 12250 rpm. Straight abrasive nozzle. The quality of the product is controlled by the manufacturer at every stage of production.

The average cost is 38 rubles.

Dexter cutting wheel, 125*1*22 mm

Advantages:

• performance;
• quality;
• strength;
• safety;
• wear resistance;
• value for money.

Flaws:

• none.

Dexter, 125*1.6*22 mm

The product is manufactured by a Polish company. There were no complaints about quality. Defects are not found on sale. It’s difficult to classify them as new. For a long time it has been the most sold product in this segment. Quantity per package – 1 piece. Will strengthen interaction with acid-resistant and heat-resistant steel, as well as stainless steel. The main component is aluminum oxide. Outer diameter – 12.5 cm. Suitable for all modern grinding machines. Disk of increased thickness – 1.6 mm, straight shape. Belongs to the category of abrasive. You can purchase it at specialized retail outlets or place an order in an online store.

Purchase price – 46 rubles.

Dexter cutting wheel, 125*1.6*22 mm

Advantages:

• strength;
• wear resistance;
• performance;
• reliability.

Flaws:

• not installed.

Bosch, 125*1*22.23 mm

The circle can easily and simply cope with metal structures. The product is straight-shaped, 1 mm thick. Outer diameter – 12.5 cm, landing – 22.23 mm. Can be purchased for any modern grinder. The surface is made of stainless steel. Rotation speed – 12250 rpm. Produced at Chinese production facilities. The reviews are only positive.

The purchase price is 70 rubles.

Bosch cutting wheel, 125*1*22.23 mm

Advantages:

• strength of the raw materials used;
• durability;
• practicality;
• reliability;
• safety.

Flaws:

• not found.

Dexter, 125*1.6*22 mm

A Polish manufacturer has launched the production of cutting discs for aluminum. They are distinguished by reliability, strength and durability. Completely exhaust the established working resource. Rotation speed – 12250 rpm. Belongs to the specialized category. Used to work with products made of aluminum and its alloys. The main material of manufacture is aluminum oxide. There are practically no foreign impurities, which significantly affects the quality of cutting. Can be used with any grinder with a bore diameter of 22.2 millimeters (standard parameters). To adapt a consumable to an outdated tool, you need to use the services of adapter rings. Type – abrasive, shape – straight. The reviews are only positive. Sold in individual packaging.

The average cost is 55 rubles.

Dexter cutting wheel, 125*1.6*22 mm

Advantages:

• smooth and clean cut;
• the presence of a bakelite binder helps reduce the level of temperature effects on the metal surface;
• interacts well with viscous materials;
• does not break;
• reliability;
• strength;
• safety.

Flaws:

• not identified.