Today, in every store that specializes in devices for building and home, you can find a huge range of grinding machines, but it is often very difficult to choose the right one. Let's try together to understand the grinders to make the right choice.
Angle Grinders (Bulgarian)
First of all, it should be said about angle grinders (grinders).
They stand apart in the series of grinding machines - they are used not only for grinding, but also for cutting. LBM can cut metal, stone, concrete, but they can not be used for wood (the density of this material is too low). Versatility is provided by working nozzles. Grinding wheels for Bulgarians are very different - brush, pan, disc, peeling, cutting, etc.
Angular grinders received the name because of the angular reducer.
The possibilities of LBM depend on the diameter and power. For example, a company Makita has in the model range as household grinders with discs from 125 mm and weighing 1.5 kg, and professional machines weighing 5 kg. Their difference in maximum performance and reliability.
If it is necessary to make grinding in places where the ordinary Bulgarian cannot reach, then you should buy direct grinding machine. Its principle of operation is about the same as that of the angular, but the direct gear and long spindle make it more nosy. Some models have a start switch lock. This feature allows you to not allow the device to "burn out" during prolonged operation. All the same company Makita has in the arsenal of direct grinders with the system SJS (Super Joint System), which simultaneously reduces vibration, extends the service life of the tool and increases the protection of the user.
Next class grinding machines - tape. Trailer rollers on which the looped abrasive belt is stretched (the belt with which the grinding is carried out) is what this type of grinder represents. The weight of models can be from three to five kg, and power - 650-1200 watts. At the same time, belt sanders have another important characteristic - the size of the working area (width). It can be 75-100 mm. In just one minute, such a unit can remove 15 grams of surface from the material being processed. This machine can be used for primary processing (quick and rough grinding) of a large surface made of wood, metal, concrete or plastic. Also, a belt sander can be used for stripping and grinding. For work with small parts, there is the possibility of a stationary installation of a sander (when the machine is turned over and the workpiece is held in the hands, but not the grinder). In general, for finer work it is better to use a tape file. Its design features allow grinding in hard to reach places.
Another view grinders - this brush brushes. Unlike tape, they have only one video. He is wearing a nylon or metal mesh. Such a tool can easily remove a layer of paint, varnish or rust from a metal or wooden surface. In addition, the apparatus is suitable for wood structuring. For polishing, you can use special polishing rings, if there is a necessary shaft-mandrel.
More fine grinding can be done and vibration grinding machine. You can also hear such a name as a surface grinder. This tool has a flat sole that moves forward and backward (reciprocating). The amplitude of such movements is small, but here is the maximum speed. At the same time, the quality of material processing depends on how small the amplitude is. Abrasive sandpaper is fixed on the sole, which is used for grinding.
The sanding skin can be fastened due to velcro or snaps. The second method is more practical. In machines manufactured by the company BoshThere is a removable work platform. This allows you to use both methods of fastening the skin.
When choosing such a tool you should not be afraid of its low power. It is rare to find a surface grinder with an engine of more than 600 watts. This is also a plus, as the tool is characterized by maneuverability and ease. Due to the finely porous polymer lining of the sole, the abrasive paper is as close as possible to the surface to be treated. This qualitatively improves the grinding process. With this tool, you can process the material along the edge with a snug fit to the mating element.
More functional are delta grinders. They have a triangle shaped forward working platform. Having a similar principle of action, the tool is endowed with more ample opportunities. Small dimensions and design features allow you to process workpieces that have a complex shape. Sanding sheets for this type of tool are fixed only on velcro.
Masterfully cope with fine grinding eccentric sanders. At the same time, the company produces especially high-quality tools. Dewalt. The working element of the grinder combines both rotational and oscillatory movements at once. All the same abrasive sheets are attached to the work surface. For concave and convex surfaces, an elastic round “plate” is used. Also, the machines are compact and have a small power of 200-450 watts. Power is directly proportional to the diameter of the working surface. However, eccentric sanders with the greatest power and diameter of the working surface make rougher grinding. The smaller the diameter, the better the work will be done. For the final processing of the material is to choose tools with an amplitude of less than 3 mm. For quick processing, you can use tools that have a stroke amplitude of more than 5 mm. Also the quality of the processing is influenced by the type of abrasive (depending on the grain). It is attached with velcro.
Choosing a manufacturer
High-quality grinding machines are produced by companies such as Interskol Bosh, Hitachi, Makita, Dewalt. No wonder these brands are on everyone's lips. The durability of the instruments of these companies is combined with excellent performance, high efficiency and reliability of engines of the most varied power.
Models are double insulated, and most also have a built-in dust extraction system. For this machine is equipped with a special dust collector. It is also possible to connect them to an industrial vacuum cleaner. And all this is combined with an affordable price. Another of the advantages of these tools is an excellent ergonomics.
Of the imported manufacturers of grinding machines is still worth highlighting Skil, Meister, Metabo, KRESS, and Black & decker. Quality Russian brands are Bison and Interskol.
Mark Makita - this is the pride of Austria and Germany. The grinders of this company are a joint product of these countries spirit. The main model range is represented by professional tools, however, household models are also quite diverse. Convenience, reliability and the ratio of quality and price are the main features of the tools of this company. The largest range of "Makita" among tape machines. Increased sealing of the engine - this is the difference of the vibration grinders of this company. Maximum performance is represented by grinders and eccentrics.
Prices for the tools of this company are very diverse (this is due to the huge selection of models). For example, an eccentric grinder from Makita can be bought for 3-12 thousand rubles. The price for vibrating grinders is 1.5-8 thousand, brush grinders - 12-16 thousand, belt grinders - 4-10 thousand, and the price of grinders is about 6 thousand. Battery grinders are more expensive by several thousand rubles. The most expensive are concrete grinders (from 20 thousand rubles).
Japanese brand Hitachi - It is a guarantee of durability and safety. The performance and reliability of the grinders of this brand is not worse than the Makita. The company specializes in premium tools. The brand exists more than fifty years. During this time, the company managed to create and patent many developments and technologies. The range of grinders is rich in both the class of household tools and professional.
The Hitachi belt grinder can be bought for 4-8 thousand rubles, vibration for 2.5-4 thousand, polishing 6-9 thousand, and eccentric for just 1 thousand rubles. The Hitachi grinders are represented by a huge model range, so the price range is from 2 to 10 thousand rubles. Battery grinder can be bought for 14 thousand rubles.
German brand Bosch everyone has heard about it for more than a decade. Swiss and German production is represented by a range of professional tools. Poland and China manufactures household grinding machines of this company. The most popular are Bosch belt and eccentric grinders, as they are the most highly efficient.
The price of Bosch vibration grinders is 4-8 thousand rubles, eccentric - 3-6 thousand, grinders for concrete - from 16 thousand, straight - 16-20 thousand, belt - 6-10 thousand rubles. Bulgarian Bosch also presented a wide range and their price ranges from 2.5 to 8 thousand rubles.
Company Meister - a fairly fresh brand, which is distinguished by its reasonable prices for high-quality goods. Meister grinders of German production, they are convenient and easy to use when working. Such tools are suitable for both home and garden, and for construction work.
Household or professional?
It is worth remembering that sanding machines (like many other tools) are divided into professional and household. When buying it is necessary to clearly define the amount of work that will be performed by this tool. Household quality grinder can "kill" even a one-time use in the event that the tool was used for a long time without interruptions. Professional tools are designed for long-term and highly productive work. Such grinders are able to withstand quite large loads.
So, for professional models of grinding machines long continuous work is not terrible. For the manufacture of such tools using the highest quality and reliable materials. At the same time, the reliability of electronics is at a higher level. Work in multi-shift mode with intensive use will not withstand any household grinder, so its purchase will be simply irrational. Of course, the maximum performance is reflected in engine power and tool size, and, accordingly, in its price. However, it is not worth saving if you are going to work with a grinder for more than 20 hours per month. It is on these numbers should be guided when buying a household grinder. It has a smaller size and a smaller set of additional functions. After every 10-20 minutes of work, it is worth giving the instrument a rest for 15-20 minutes, otherwise it is fraught with overheating and breakage. On the day, do not use the tool for more than two or three hours. As a result, the advantages can be attributed only to compactness and low price. However, to work in the country or at home, this tool will fit perfectly, so you should not spend extra money on a professional unit.
Useful tips when working with a grinder
If you need to grind varnished the surface, it is worthwhile to put the tool at the lowest possible speed, since the varnished coating is sensitive to high temperatures. It is necessary to monitor the temperature regime and regularly let the surface “cool” after each grinding stage. In order not to create excessive friction, it is worth using pure abrasives and not pressing with force on the tool.
If you need to polish plasticit is best to use an eccentric or vibration grinder. Again it is necessary to set the minimum tool speed. The grain of the skin at this should be more than 240.
Similar types of machines should be used if you need to polish metal surface. However, the grain should already be more than 600. To grind irregularities, you have to use the grinder. If you need a finer processing of the material, then you should think about the use of fiber or fan discs.
Tape Grinder must first be turned on, and only then brought to the surface, which must be processed. Otherwise, the tool can be dropped from the workpiece at high speed (up to 25 km / h). When grinding it is not necessary to strongly press on the machine. Regular contact of surfaces is enough for an effective grinding process. With a strong pressure I will eat the material will be produced in increased volume, but this will affect the quality of grinding.
Working with grinderBe sure to use safety glasses. These grinders are the most traumatic. To keep the instrument working stably, regularly remove dust from the cavities of the grinder. This can be done by blowing and tapping the case. Avoid overloading. In this case, the tool life will be maximized. The ends of the material being processed should not have a snack cutting disc, otherwise its lifespan will not be long. To avoid this, it is necessary to provide constant pressure on the grinder. At the same time, you shouldn’t make very deep cuts in one run, as the loads on the motor increase significantly, which can cause damage to even a professional angle grinder.