Diamond blades are the best setting for concrete!
Natural diamonds were used in stone processing back in the days of Ancient Rome, but the first attempts to create a full-fledged cut-off diamond tool date back to the 30s of the 20th century. Their authorship belongs to a watchmaker from Switzerland. Then the direction of diamond processing began to develop in the 50s: for the first time artificial diamond was synthesized in 1956. The patent is held by General Electric.
Developments were also carried out in the USSR. In 1960, the Institute for High Pressure Physics developed an artificial diamond substitute, which gave a powerful impetus to the development of the industry. Already in the 60-70s, diamond tools with a high resource were used in construction when processing stone, ceramic tiles and granites. At the turn of the 1980s and 1990s, the wave of perestroika washed away all the successful developments in the creation of artificial diamonds. The production of tooling for cutting hard materials had to start from scratch. In modern construction, a wide variety of tools are used for processing: diamond crowns, drills, cutters, strings, etc. Diamond discs (cutting or grinding wheels) deserve special attention.
Cutting with diamond blades
Depending on the material for which the disc is made, diamonds are selected, their number and size, as well as the stiffness of the bond.
Diamond discs for concrete are different from those for granite and marble. For the processing of granite, diamonds with high static strength, large and with a long resource are “introduced” into the segment. The same can be said about marble, only the wear resistance will be lower here. A circle on concrete has small diamonds, strongly protruding and fragile.
The stiffness of the bond depends on the material being processed: for soft marble a hard bond is needed, for hard concrete. a soft bond, and for diamond wheels on reinforced concrete. a very hard bond. Tooling for highly reinforced concrete has a corrugated cutting surface to reduce “greasing”
Sometimes segments of even an expensive diamond blade become smooth and stop cutting. Most likely, such a circle is intended for a more abrasive material, and its bond is strong, therefore it does not open. The ability of a segment to work with a particular material can be judged by whether it overheats or not. By the way, the disc can cut even when overheated if it has strong diamonds.
The number and shape of diamond segments. Typically, 16-18 segments are “planted” on cutting discs with an outer diameter of 230 mm. Their number is a matter of price and performance. A diamond blade for cutting with a large number of segments, all other things being equal, will cut faster. But, the fewer segments on the disk, the less its cost.
Overheating of the diamond tooling is caused by the wear of the disc or incompatibility with the material. In the second case, the rigid bond rubs against the concrete, but does not break open. In this case, the resource may not be used up.
Many experienced users do not discard any abrasive cut-off wheels that have worn out, but place them on a small “angle grinder”. Something similar is done with diamond discs, only they replace not the tool, but the material. So, diamond tooling, unable to cope with M500 concrete, will cut asphalt well.
What are diamond discs?
Wheels with a solid cutting edge are the least productive. They are designed for accurate cutting of fragile materials (ceramic tiles, etc.).
Segmented diamond discs are divided into “segments” (of different shapes, quantities and sizes). Segments come in different shapes depending on the type of work. Designed for cutting concrete, granite, asphalt and other hard materials.
The turbo cut-off discs are distinguished by special channels through which dust is quickly removed. They are used for high speed cutting of asphalt, concrete and stone.
- For wet cutting: the segment is brazed with silver solder for cooling;
- For dry cutting: diamond segments are soldered by laser welding (for thin reinforcement and concrete);
- Universal discs.
Cutting wheels can be different: from standard 115-230 mm to 1.5 m.The diameters of diamond discs are selected for the work to be performed, and for the diameters of the bore holes in the cutting equipment.
Cutting disc production
The stages of manufacturing segment wheels are the production of segments, their connection to the body and the opening of the diamond layer. Manufacturing technologies for diamond discs can be different and affect the price of the product. Various technological solutions are used in the production of diamond tools:
- Electroplating method. They are used for cheap diamond wheels with a low resource. The body is immersed in an electrolyte containing a mixture with diamonds and a current is applied. This cutting tool is suitable for household work.
- Sintering of diamond discs with previous “cold” pressing. It takes place before processing by temperature and pressure.
- Backfilling the disc without preliminary “compression”. The bonding material is a copper-tin alloy with additions of cobalt, iron or other metals. The stiffness of the bond is set by a different combination of “components”: it depends on the specialization of the cutting wheel.
Then the diamond segments are attached to the body in one of the following ways:
- Laser welding: expensive, high “seam” strength and resource;
- High temperature solder: the cost is lower, but the “joint” is not so resistant to overheating;
- “Baking” a diamond layer onto the disc body.
Artificial diamond for stone processing and its advantages
Natural analogues were distinguished by a high price, so their mass use in construction was impossible. In addition, due to impurities, the stone could not boast of strength, and the shapes were not always suitable, and different materials require diamonds of different sizes.
The artificial substitute solved all the problems. The graphite raw material is mixed with iron, manganese, cobalt and nickel, and then processed at high temperature and pressure. And they get an inexpensive, hard and durable diamond stone, which can be given the desired shape and size and used for processing stone, concrete, asphalt, granite and porcelain stoneware, marble, ceramic tiles and other building materials.
Choosing a diamond wheel for cutting
The standard question is: how to choose a diamond wheel? For household work, Chinese discs at a low price and with a small resource are quite suitable. If you use such blades for cutting extremely rarely, then the option is optimal. It is important to choose the right diamond tooling for the material, although there are universal discs: for concrete, stone, asphalt. The attitude towards them is ambiguous. Some experts argue that this is not a diamond tool, but a disposable blank with diamonds, others praise them for their ability to cut materials that are very different in properties.
If intensive processing work is expected, then you should not save money, it is better to take a professional tool. One diamond disc for 5000 rubles will last longer than ten circles of 500. over, there are many manufacturers of rifling equipment on the market who produce relatively inexpensive, but fairly high-quality discs. In most cases, these are companies specializing in diamond cutting and abrasive tools.
Diamond blades for cutting metal are made of steel. Diamond is applied to the cutting edge. This type of wheel cuts and grinds any metal. Advantages. no sparks and no smell, long service life. Disadvantages. high price and the need to take frequent breaks (the diamond cutting wheel is afraid of overheating).
Carbide. instead of diamond spraying, they have high-carbon molybdenum steels with additions of chromium and nickel at the edges. There are special-purpose carbide discs on sale: for thin, high-carbon, stainless steel, aluminum.
From metal wire
Disc brushes are made of twisted steel wire. They are designed for rough cleaning work: removing rust, scale, old paint, other types of stubborn deposits, burrs, and seams. There are two types of brushes in shape: ring (solid circle), braided (from twisted wire bundles).
Angle grinder discs for metal work
Discs for an angle grinder for metal are selected taking into account a number of parameters. The outer and inner dimensions are important, for which work the wheel is needed, the material of the disc and abrasive, the characteristics of the abrasive chips, the maximum permissible rotation speed, etc.
The cutting depth, the types of work that can be performed by it, the service life (for cutting wheels), compatibility with a particular tool depend on the size of the disc. You need to select the right one, taking into account the brand of the angle grinder, its power and the bore diameter.
Possible outer diameters of discs for metal for an angle grinder: 115, 125, 150, 180, 230 mm. Large outer diameters are not suitable for household tools. They are most often used in manufacturing. The outer diameter of the attachment must match the size of the guard of the angle grinder. The inner (landing) diameter must match the size of the tool shaft. The most common shaft diameter of household angle grinders is 22.2 mm.
How It’s Made Grinding Wheels
The circles also differ in thickness. The thickness of the cut depends on this parameter. A thin disc makes thinner cuts, but will also last less than a thick one. Possible circle thickness: 1; 1.2; 1.6; 1.8; 2; 2.5; 3.2 mm. You can use a disc that is no more than 35% worn out.
Classification by type of work
Types of metal processing with an angle grinder:
- removing the old paint layer, including from metal surfaces;
- removal of rust, scale, dirt;
- processing of welded seams;
- grinding and polishing.
- Cut-off. They are designed for making cuts. The cutting discs for the metal angle grinder have a solid or segmented cutting edge. They are made from several types of materials. The difference in service life, price, work features. The thickness of the cut-off wheel also plays a significant role. The thickness of the cuts and the durability of the nozzle depend on it.
- Roughing (grinding). for grinding and removing the old layer of paint, varnish, etc. from the metal surface. A type of roughing discs. flap: end, batch, with a mandrel. They are used in metal processing, cleaning welded seams and burrs, removing rust, etc. The end wheel is suitable for processing at an angle and normal flat. The batch disk is used when working over a large area. Mandrel wheels are used when working with cavities. Flap disc works smoother than conventional sander.
- Stripping. to remove rust, stubborn dirt. These include disc brushes made of hard metal wire.
- Polishing. for final polishing of surfaces. These include interchangeable polishing cloth, foam and fur attachments. Metal polishing can only be done with a variable speed angle grinder.
Use of discs for other purposes (for example, a cutting disc for an angle grinder instead of a grinder) is not allowed.
The circle label indicates the expiration date, the maximum number of revolutions, the material marking, coded in letters and numbers. After the expiration date, the nozzles become brittle, the abrasive crumbles. The date until which the disc can be used is shown on the label next to the bore hole.
Amazing Angle Grinder Discs For Any Works
When buying, you need to pay attention to the maximum number of revolutions. It must be equal to or less than that of the instrument.
Abrasive discs for an angle grinder must have a coded marking of the abrasive material. Material encoding is deciphered as follows:
- The material from which the abrasive grit is made is denoted by a Latin letter (or two letters). For example, for a circle with a marking starting with the letter A, the abrasive consists of aluminum oxide. White corundum (AS). does not cut stainless steel, silicon carbide (C). generally not suitable for working with metals.
- The grain size of the abrasive is indicated by the number following the letter designation of the type of abrasive grit. The larger the value, the smaller the particle size. To work with ferrous metals, you need wheels with coarse-grained abrasive (up to 30), for non-ferrous metals, fine-grained (from 40) are suitable.
- The hardness of the bond of the abrasive is indicated after the grit. It is denoted by a Latin letter. The further the letter is from the beginning of the alphabet, the harder the abrasive is. The softest bond is A, the toughest bond is Z. Soft abrasive tips are used for hard metals. A hard bond overheats the surface to be processed, cuts with difficulty. The soft ligament will wear out quickly.
- The ligament material is designated by one or two Latin letters at the end of the encoding.
For example, a disc marked A24R BF. alumina abrasive, coarse-grained, soft, bakelite bond.
The backing of the abrasive wheel is made of fiber or thick waterproof latex paper. There is a reinforcing mesh between the layers of paper. A layer of abrasive material is applied to the base. particles of zirconate or aluminum oxide, tungsten carbide, ceramic grain or corundum. The binder for the abrasive is resin or polymer. Cutting wheels for angle 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, sparks emission during operation. Cutting metal with an abrasive wheel is accompanied by an unpleasant odor.
The metal cutting disc can be made of paper with a reinforcing mesh. Fiber discs are used only for grinding and polishing, always with a plastic or rubber backing pad. It serves as a stop and cools the abrasive. Fiber discs are ideal for rough removal of old paint. Abrasives include emery flap attachments designed for processing welded seams.
In fact, this is a kind of sandpaper in the shape of a circle. The base is paper coated with microfiber, and electrocorundum (refractory and chemically resistant superhard material) is used as an abrasive. Emery cloth is tightly attached to a special nozzle of a flat or curved shape. In addition to the electric angle grinder, pneumatic is often used as a tool for sanding wood.
In the second case, we are talking about grinding emery wheels with perforation. These are used for grinding wood, natural and artificial stone, gypsum, cleaning metal from rust. In the first, the plate has concentric slots in the center. Such a disc engages on a curved glass fiber reinforced plastic base.
GRINDING AND SHARPENING WHEELS
It is used for grinding ends, edges and smoothing edges. The working surface is parallel to the longitudinal axis of the grinder, flat or slightly convex.
These cutting discs for an angle grinder are made of metal. The base material is high-carbon steel with the addition of alloying components. The metal has a low coefficient of thermal expansion so that the tool heated from friction does not wedge during cutting.
The cutting part contains abrasive particles. In diamond discs, the edge is formed by powder spraying of an abrasive. Wheels for woodworking are coated with carbide powder.
Designed for cutting workpieces and products from plastic, metal, stone and silicon. They have a number of characteristic features:
- these are double-edged discs;
- the edge is solid, segmented or with a “turbo segment” (universal for dry and wet cutting).
Where to install which?
The cut-off wheel for the hand-held angle grinder is selected with a diameter ranging from 115 to 250 mm. Larger discs are installed only on stationary turbo cutters, which cut through concrete, asphalt, natural stone and ceramics.
Distinguish between dry and wet cutting. The first option is suitable for more rough work. On dry cut brick, concrete, stone, wood, ferrous and non-ferrous metals. Segmented circles are used for dry cutting.
Wet cutting is recommended when cutting through hard but brittle materials: minerals based on silicon oxide, ceramics, glass, porcelain stoneware. The supply of water to the cutting area allows you to simultaneously grind the edge, to obtain neat edges without chips. When cutting glass and ceramic decorative elements, wet cutting is always preferable. For her, solid diamond circles are like.
The “turbo segment” blade is versatile for dry and wet cutting. It also costs less than a solid one, but you should not consider it an equivalent replacement. The shape of the cut when using it is still different and it is adapted for longer continuous cutting. Therefore, a diamond disc for concrete is more suitable (for chipping).
Angle Grinder Disc Types in Detail
What are cutting and grinding wheels?
What discs do you need for an angle grinder? We are sure that you, like many other buyers, are concerned about this issue. There is still no consensus among professionals about the advisability of using this or that tool and attachment when working with wood, stone, metal and concrete. It is enough to know the cardinal differences in the design and the manufacturer’s recommendations, which will help you choose the desired grinding or cutting disc. Based on them, we will tell you which types of grinding discs are best suited for a particular type of work.
WHAT DISCS FOR ANGLE GRINDER ARE MEETING FOR SALE?
The modern market for consumables is bursting with the abundance of both the angle grinders themselves (angle grinder) and attachments for them.
PKF Komplekt officially represents the KLINGSPOR company in the south of Ukraine. This organization stood at the origins of the serial production of abrasive materials, contributed to the development of their production and standardization. KLINGSPOR pioneered the creation of OSA, the Abrasives Safety Organization. OSA is committed to bringing together the expertise of manufacturers to improve product quality and improve abrasive tools in terms of safety and efficiency. KLINGSPOR products are standardized according to the GOST and EN systems, which determine the standard sizes of grinding wheels, the composition of the binder, the grain size of abrasive inclusions, etc.
Flap (end) circles are necessary for trimming the ends and sides of the product, cleaning grooves and undercuts. The disc is rectangular or slightly curved when viewed from the side. Face bits are widely used as grinding wheels for metal. They are found in auto repair shops (body repair), construction, metalworking, baths, swimming pools and artificial reservoirs.
The disc has a bakelite base. On top of it, petals made of hard felt or reinforced cotton fabric are attached. The petals are overlapped and at an angle, like a turbine impeller. This design reduces friction and promotes more material removal. It is pleasantly pleasing that such a disk will serve until the petals are completely worn out.
ABRASIVE CUT-OFF DISCS
Wheels of this type are formed from at least two layers of fiberglass mesh, on top of which a mass of abrasive materials is applied. Are flat and concave.
Such discs are suitable for operation until the disc is almost completely worn out. They are used for cutting ferrous and non-ferrous metals, as well as their alloys. They can be used as an attachment for an angle grinder for wood and cut a beam of small thickness, but are of little use for this, since they get stuck in it due to the resin. Abrasive discs are completely unsuitable for cutting hard metals and stone, from building materials they can easily cut fragile limestone.