The active development and emergence of new building materials contributed to the improvement of the performance of critical structures, finishing coatings, functional parts, etc. Moreover, traditional materials do not lose their popularity, while retaining their leading positions in many segments. This also applies to concrete, the strength of which, coupled with an affordable price, determines its widespread demand.
Of course, it also has drawbacks, which are also expressed by the complexity of the machining. Specially designed for solving such problems, a concrete grinder with various technical and operational indicators is intended. In particular, it is used to clean all kinds of nicks and surfaces on the target surface.
Where is the tool used?
The main objective of such devices is to improve the aesthetic appearance of solid-state 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 provides the ability to process surfaces in hard-to-reach places - the dimensions of a particular model and its mass will affect the effectiveness of solving such operations.
It is worth noting the versatility of the tool in terms of working with a wide range of materials. For example, a Bosch concrete grinder in the GBR 15 CA modification successfully cleans mineral building materials, including marble, artificial stone, seamless casting screeds, etc. As for the removed defects, these may be glue residues, old paint, unevenness after the removed nails and other defects.
Grinder device
The main components of the tool include a gearbox, an electric motor, running gear, 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 constructional addition is a vacuum cleaner. Even inexpensive modifications to the tool have a special pipe through which you can connect a construction vacuum cleaner. Since manual grinders on concrete allow direct emission of dust waste in the working area, the master’s airways will also require special protection from harmful dust. On the one hand, the dust container minimizes waste volumes, and on the other hand, it is not 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 in the housing.
Specifications
Concrete coatings and structures require the use of a powerful tool, so the capabilities of the engine come first 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. The power potential of the unit will affect the speed of rotation of the working body, which will affect the quality of grinding. Therefore, the following 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 rough surfaces, and with delicate coatings in the form of screeds, which require fine adjustment at high speeds. At the same time, as practice shows, it is more important not even the maximum speed of rotation, but the ability to adjust the frequency to certain indicators - this function makes the tool a universal grinder.
From an ergonomic point of view, weight and dimensions are also taken into account. Lightweight and nimble machine will allow you to perform work for a long time without overloading your hands. On the contrary, a heavy model will quickly lead to fatigue, although productivity in this case will be higher. By weight, the range of values varies from 2 to 3 kg.
Tooling Features
Abrasives for grinders represent a wide range of consumables, differing in size and purpose. In this case, two types of equipment are most common - with sizes 125 and 225 mm. The grinding operation is performed by wear-resistant corundum, silicon carbide and diamond disks. Separation also takes place according to the degree of hardness and granularity. If the marking indicates a high level of grain (grades 100-120), this means that the consumable is suitable for fine processing.
Coarse disks, in contrast, are designed to remove thick layers from the surface. In addition, a concrete grinder can use different abrasive wheels in design. The same diamond products can be solid and segmented. Due to the presence of grooves, the models of the second type not only have a more effective 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 solid surfaces can be processed with different types of grinders. They can differ in their constructional structure, power system, the 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 latch for working equipment. Additional housing support may be provided by an attachable side handle. Abrasive wheels are used as a functional organ. Eccentric models differ in that the mounting 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 to carry out the impact not only by rotating the disk, but also by changing the pressure force.
Soft processing is carried out by models with a D-shaped design, which are used as accessories foam rubber, fur and felt circles. This is a concrete polisher grinding machine operating at reduced speeds. It also provides for a more delicate adjustment of the intensity of rotation in such an instrument, which allows you to precisely adjust the device to the optimal operating conditions.
Functional support
The quality of the result and the convenience of the workflow for the user himself are affected by the set of functions of the tool. What should be considered in this parameter? The entire option can be divided into three groups:
- Ergonomic additions. This category of functions includes the ability to adjust speed, smooth start, maintaining maximum speed, etc.
- Protective systems. These are the means by which overloads and overheating of the tool are eliminated. A high-tech concrete grinder is able to automatically shut off if the engine has been operating at the limit of its potential for a long time. There are also mechanisms to prevent accidental start-up, jamming of equipment and strong vibrations.
- Assistive devices. Additional structural devices include the same side handles, dust collectors, housings, etc.
Bosch GBR 15 CA model reviews
One of the most powerful devices in the segment, with a capacity of 1,500 W and working with discs with a diameter of 125 mm. The model provides the function of supporting constant revolutions under high load, soft start of the engine and a pipe for connecting the construction pump. Although there is no special protection against engine overheating, users note that even at peak speeds, the filling is heated uncritically.
The most important advantage of the Bosch GBR 15 CA concrete grinder is called productivity. In particular, we can talk about the thorough processing of 40-50 m 2 for a full day. The only serious drawbacks are the price tag of 27 thousand rubles. But taking into account the quality of the elemental base, the absence of strong vibrations and, on the whole, belonging to the professional class, this amount justifies itself.
Makita PW 5000 CH model reviews
In this model, the emphasis is on a wide range of operations and polishing of concrete surfaces according to the type of "wet" abrasive impact. The power of the tool is 900 watts, and the number of revolutions varies from 2000 to 4000. Reviews note that the unit copes well with the basic tasks of thin cleaning concrete and mosaic surfaces, leaving a minimum of dirt and dust.
In terms of cons, many indicate a lack of tightness of the case. So, during long working sessions, water can penetrate inward to the engine. For a concrete grinder, the price of which is about 17 thousand rubles, this is a significant flaw.
Reviews about the model -125 / 1400 "Interskol"
Angle grinder of domestic production, which is a budget solution for domestic needs. The device has a rather high power (1400 W) and many useful functions, but in terms of overall quality this is not the best option. As the owners note, the Interskol concrete grinder of this version is equipped with consumables with small deformations. This applies to the polishing wheel, in which the villi are curved, which in itself is not suitable for delicate operations. Technical power filling at high power also does not cope with long working sessions due to rapid heating and overload.
Homemade grinder
For the independent manufacture of this tool, 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 disk fixing unit to the motor on the shaft like conventional angle grinders. Next, the power unit is attached to a wooden frame, with the help of which the correct position of the tool on the surface will be ensured. In the same wooden structure, a niche should be provided for the battery, the energy consumption of which is enough to power a medium-power grinder for concrete.
With your own hands, you can also make ergonomic accessories from handy 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 ennoble the appearance of a concrete surface can be different. The choice of a technical tool for solving such problems is determined by the state of the target site. For example, 1500 Watt Bosch concrete grinders are ideally suited for the regular cleaning of coarse, freshly cast screeds. A powerful and hardy unit will provide an equalization effect - you just need to choose the optimal consumable with sufficient grain size.
Another approach is offered by developers of low-power grinders, which are more likely to polish. They are recommended to be used at the final stage of surface preparation for decorative design, when getting rid of minor coating defects is required.