Active development and the emergence of new building materials have contributed to improving the performance of critical structures, finishing coatings, functional parts, etc. At the same time, traditional materials do not lose their popularity, maintaining their leading positions in many segments. This also applies to concrete, whose strength, coupled with an affordable price, determines its wide demand.
Of course, it also has disadvantages, which are also expressed by the complexity of machining. Especially for solving such problems, a concrete grinder with different technical and operational indicators is designed. In particular, it is used to gently clean all kinds of nicks and surfaces on the target surface.
Where is the tool used?
The main task of such devices is to improve the aesthetic appearance of hard coatings. The main directions of their use are industry, civil and private construction. An important feature of this type of grinder is maneuverability and mobility. The manual design also makes it possible to process surfaces in hard-to-reach places - for the effectiveness of the solutionsuch operations will be affected by the dimensions of a particular model and its weight.
It is worth noting the versatility of the tool in terms of working with a wide range of materials. For example, the Bosch concrete grinder in the GBR 15 CA modification successfully cleans mineral building materials, including marble, artificial stone, seamless self-leveling screeds, etc. As for the defects to be removed, these can be glue residues, old paint, irregularities after the removed nails and other defects.
Grinding machine
The main components of the tool include a gearbox, an electric motor, running equipment, a traverse with runners and a body handle. Depending on the specific tasks, the grinder may have one or more landing links for installing abrasive material. An important optional design addition is a dust extractor. Even inexpensive tool modifications have a special pipe through which you can connect a construction vacuum cleaner. Since manual concrete grinders allow direct release of waste dust into the working area, the airways of the master will require special protection against harmful dust. On the one hand, the volume of waste minimizes the dust collector, and on the other hand, it will not be superfluous to use a respirator for protection. By the way, some models also have additional physical protection in the form of a casing with a screen as part of the case.
Specifications
Concrete pavements and structures require a powerful tool, so the engine's capabilitiescome out on top when choosing a specific version. The average range for this parameter is 1000-1500 watts. Accordingly, this is the average distance from household models to semi- or professional ones. The power potential of the unit will affect the rotation speed of the working body, which will affect the quality of grinding. Therefore, the next significant characteristic is reflected in the number of revolutions. On average, it is 0-9000 rpm. This means that the concrete grinder will be able to work with both rough surfaces and delicate screed coatings that require fine adjustment at high speeds. At the same time, as practice shows, it is not even the maximum rotation speed that is more important, but the ability to adjust the frequency to certain indicators - it is this function that makes the tool a universal grinder.
From the point of view of ergonomics, weight and dimensions are also taken into account. The light and nimble device will allow you to work for a long time without overloading your hands. On the contrary, a heavy model will quickly lead to fatigue, although the performance in this case will be higher. By weight, the range of values varies from 2 to 3 kg.
Tool accessories specifications
Abrasives for grinders represent a wide range of consumables that differ in size and purpose. In this case, two types of equipment are most common - with standard sizes of 125 and 225 mm. The grinding operation is performed with wear-resistant corundum, silicon carbide and diamond discs. Separation also takes place according to the degree of hardness and granularity. If in the labela high grain level is indicated (grades 100-120), which means that the consumable is suitable for fine processing.
Coarse-grained discs, on the other hand, are designed to remove thick layers from the surface. In addition, a concrete grinder can use abrasive wheels of different design. The same diamond products can be solid and segmented. Due to the presence of grooves, models of the second type not only have a more efficient mechanical effect, but also create channels for air circulation, which allows cooling both the consumable and the tool itself during the operation.
Varieties of models
Concrete and other hard surfaces can be machined with different types of grinders. They may differ in their structural design, power supply system, nature of mechanical abrasive action, etc. Angular and eccentric models are most often used. In the first case, the design is based on a narrow cylindrical body, which smoothly passes into the part with a clamp for working equipment. Additional body support can be provided by an attachable side handle. Abrasive wheels are used as a functional organ. Eccentric models are distinguished by the fact that the fastening mechanism is not implemented in a separate remote part of the body, but is directly integrated into the sole of the structure. This allows in the process of work to carry out the impact not only by rotating the disk, but also by changing the clamping force.
Soft processing is carried out by models withD-shaped design, which are equipped with foam, fur and felt circles. This is already a polishing grinder for concrete, operating at low speeds. Also provided in such a tool is a more delicate adjustment of the intensity of rotation, which allows you to fine-tune the device to optimal operating modes.
Functional support
The set of tool functions also affects the quality of the result and the convenience of the workflow for the user himself. What should be taken into account in this parameter? The whole optional can be divided into three groups:
- Ergonomic additions. This category of features includes the ability to adjust speed, soft start, maintain maximum speed, etc.
- Protection systems. These are the means by which overloads and overheating of the tool are excluded. The high-tech concrete grinder is able to automatically turn off if the motor runs at the limit of permissible potential for a long time. There are also mechanisms to prevent accidental activation, jamming of equipment and strong vibrations.
- Accessories. Additional structural devices include the same side handles, dust collectors, covers, etc.
Reviews about the Bosch GBR 15 CA
One of the most powerful devices in the segment, with a power of 1500 W and working with discs with a diameter of 125 mm. In the modelthere is a function to maintain constant speed under high load, a soft start of the engine and a pipe for connecting a construction pump. Although there is no special protection against engine overheating, users note that even at peak speeds, the filling heats up uncritically.
The most important advantage of the Bosch GBR 15 CA concrete grinder is performance. In particular, we can talk about the thorough processing of 40-50 m2 for a full day. Serious disadvantages include perhaps a price tag of 27 thousand rubles. But given the quality of the element base, the absence of strong vibrations and, in general, belonging to the professional class, this amount justifies itself.
Reviews about the model Makita PW 5000 CH
In this model, the emphasis is on a wide range of operations and polishing of the concrete surface by the type of "wet" abrasive action. The power of the tool is 900 W, and the number of revolutions varies from 2000 to 4000. Reviews note that the unit copes well with the basic tasks of fine cleaning concrete and mosaic surfaces, leaving a minimum of dirt and dust.
In terms of cons, many point to insufficient tightness of the case. So, during long working sessions, water can penetrate inside to the engine. For a concrete grinder, the price of which is about 17 thousand rubles, this is a significant flaw.
Reviews on the model MShU-125/1400E "Interskol"
Domestic-made angle grinder, which representsis a budget solution for household needs. The device has a fairly high power (1400 W) and a lot of useful features, but in terms of overall quality, this is not the best option. According to the owners, the Interskol concrete grinder of this version is equipped with consumables with small deformations. This applies to the polishing wheel, whose bristles are curved, which in itself is not suitable for delicate operations. The technical power filling at high power also does not cope with long working sessions due to rapid heating and overload.
Homemade grinder
To make this tool yourself, you will need an electric motor (from household appliances), a wooden frame, electrical fittings, fasteners and a power source. It is also necessary to attach a disc fixation unit to the motor on the shaft, like conventional angle grinders. Next, the power unit is attached to a wooden frame, with which the correct position of the tool on the surface will be ensured. In the same wooden structure, a niche should be provided for a battery, the energy intensity of which is enough to power a medium-sized concrete grinder.
With your own hands, you can also make ergonomic additions from improvised materials in the form of handles, wheels, protective screens, etc. For this, you can use metal profiles, pipe sections and sheet metal.
Conclusion
Approaches to improving the appearance of a concrete surface can be different. The choice of one or another technical means for solving such problems is also determined by the state of the target site. For example, Bosch concrete grinders with a power of 1500 W are ideal for regular cleaning of rough, freshly poured screeds. A powerful and durable unit will also provide a leveling effect - you just need to choose the optimal consumable with sufficient grain size.
Another approach is offered by developers of low-power grinders that perform more polishing. They are recommended for use at the final stage of preparing the surface for decoration, when getting rid of minor coating defects is required.
