Comparison Revolt RS 600 3/1 vs Crown CT13560V

The type of grinder determines the design features and the operation of its working mechanism.

— Corner. One of the most common and versatile types of grinders. The name is due to the device of the working mechanism, in which the drive axle and the spindle with the working nozzle are located at an angle of 90 degrees and are connected through a gearbox. It is this type of grinders that is unofficially called "grinders". The working tool is a grinding wheel. Angle grinders are used for grinding, polishing, roughing and stripping metal, concrete, brick, cement, marble and granite products. Design features also allow the use of such a tool for cutting metal and cleaning welds.

— Direct. In straight grinders, the drive shaft of the electric motor and the spindle with the working nozzle are located on the same axis, which led to the name. Most often they are used for small and precise work, they are convenient for processing hard-to-reach surfaces (the length of the spindle is of great importance). As a working tool, finger and conical grinding wheels, cutters, brushes can be used. Not designed for use with large grinding wheels such as those used in angle grinders.

— Tape. The working element of such grinders is a sanding belt connected into a ring and moving along guide rollers. Such devices are designed for rough processing and leveling of fl...at surfaces, as well as the preparation of edges and bevels. Tape models have a fairly high performance, but are not designed for accurate delicate processing; in addition, they are intended mainly for relatively narrow parts, the width of which does not exceed the length of the tape (brush / drum devices are better suited for large surfaces — see below). Also note that grinders of this type do best with wood, although sanding belts are also available for other materials, including metal, concrete, plastic.

— Eccentric. In eccentric grinders, the working tool (sanding sheet) performs two movements simultaneously: rotational and vibrating. Due to this, high quality processing is achieved with good performance. These machines are well suited when a large amount of material has to be removed during fine finishing work. Unlike vibration grinding, they allow you to process not only flat, but also convex and concave surfaces.

— Vibrating. Orbital sanders use a vibrating sanding sheet driven by an eccentric on the motor shaft. With a relatively low productivity, such a scheme provides high accuracy and quality of processing. Vibration grinders are used for fine finishing of flat surfaces.

— Delta grinding. In fact, they are a kind of vibration grinders (see above), but they differ from them in the shape of the grinding sheet: it is triangular, resembling the Greek letter “delta” in shape (hence the name). Due to this, as well as their small size, these machines are well suited for working in hard-to-reach and difficult places, such as corners, edges, curves, etc.

— Multifunctional. Machines operating on the vibration principle, however, combining the capabilities of several varieties at once. Such versatility is realized through interchangeable soles, which, usually, are supplied in the kit. Thanks to such accessories, a multifunctional grinder is able, at a minimum, to turn from a conventional vibrating (with a rectangular sole) to a delta sander (with a triangular one) and vice versa; and some models are also equipped with a round nozzle and can also work in the eccentric format. Such a tool will be the best choice for those who have to deal with a wide variety of tasks for a vibration format machine: one universal machine with a set of interchangeable accessories is much cheaper than several more traditional tools with similar characteristics. On the other hand, a multifunctional model handles worse with each specific task than a specialized unit of a similar cost. Simply put, at the same price, a universal machine “can” more, but a specialized one (vibrating, delta grinding, etc.) is more effective in its particular area.

— Polishing. A type of angle grinder specifically designed for finishing various surfaces. Technically capable of working in grinding mode, however, the main function is still polishing and final finishing of the material.

— Brush / drum. Grinders of this type are generally similar in layout to angle grinders (see above), and the main difference is that the working nozzle does not have the shape of a flat disk, but of a characteristic cylinder, the length of which noticeably exceeds the diameter. If such a cylinder has hard bristles (usually metal) — the machine is called a brush, in other cases — a drum; however, there is no fundamental difference between these varieties, in addition, many models allow the use of both types of nozzles. This nozzle format is especially suitable for processing large flat surfaces, for which tape machines are poorly suited; specifically, the brushes are very effective, in particular, when removing paint and varnish coatings. On the other hand, removing paint is just one of many tasks that sanders have to deal with; and with other types of work available for this type of machine, vibration (including delta grinding) and eccentric models (see above) also do a good job. In addition, rotating cylindrical nozzles are not particularly accurate, they are not suitable for delicate work that requires care and precision. That is why grinders of this type are relatively rare nowadays.

— Wall grinder. A specific feature of most wall grinders is an elongated design that includes a characteristic rod (see "Complete set"). This allows you to grab a large section of the wall without moving from your place, as well as work at high heights without using stools or other similar supports. However, wall grinding models are produced without a rod. Such devices, usually, are a slightly modified version of the angle machines described above. Of the differences, in addition to the use of a rod, one can also mention the method of attaching the working nozzle — it is installed on Hook-and-loop or other similar devices, similar to how it is done in an eccentric tool.

— Grinder for concrete. Most stone/concrete grinders are similar in design to angle grinders (see above), although there are other variations. Anyway, such tools are quite powerful, and their design is designed for long-term operation in difficult conditions: for example, overload protection is often found (see "Additional"), a system for supplying water to the place of work, etc. can be provided.

Power delivered during work directly to the working nozzle. High power, on the one hand, contributes to performance, on the other hand, it significantly affects the dimensions, weight and price. Therefore, it is worth choosing a tool for this parameter, taking into account the specifics of the planned work; recommendations on specific power values for different types of work can be found in special sources.

The power consumed by the grinder during operation. Usually more than the output (useful) power (see above) due to losses during the conversion of energy from electrical to mechanical. However, the general patterns in this case are the same: a more powerful tool, on the one hand, is usually more performant, on the other hand, it is heavier, larger and more expensive. In addition, the total electricity consumption depends on this indicator; however, grinders, even the most powerful ones, consume relatively little energy, and difficulties can arise only when connecting a high-performance professional tool to weak electrical wiring.

Note that it is much easier to determine the consumed power than the useful one; therefore, only this parameter is often indicated in the characteristics, without specifying the useful power. In general, it is quite possible to compare grinders of the same type using it (see above): a modern tool has approximately the same efficiency, and in most cases the useful power values bare related in the same way as the consumed values.

The speed of rotation of the working attachment, which is capable of providing a grinder of the appropriate design (for example, angle — see "Type"). If the device has speed control, this paragraph shows the range of such adjustment, from minimum to maximum.

It makes sense to compare by this parameter units belonging to the same type and having the same maximum diameter of the disk (or other working nozzle). The latter is due to the fact that the larger the disk, the faster its edge moves (at the same speed); i.e. a larger diameter requires less RPM for the same performance/efficiency. In general, when comparing different models, the following should be taken into account. The higher rotation speed is well suited for large volumes of work (because it improves productivity) as well as for fine polishing with “delicate” nozzles. A lower setting, in turn, improves accuracy (reduces the chance of removing excess material), as well as provides more torque and allows you to more effectively deal with hard, stubborn materials. More detailed recommendations for different types of work and different nozzle diameters can be found in special sources; here we note that an increase in the rotation speed, usually, affects the cost of the machine compared to analogues (since this requires a more powerful engine). In addition, discs and other attachments may have maximum RPM limits.

The frequency of vibration of the working attachment, which is capable of providing a grinder of the appropriate design (a classic example is vibration, see "Type"). If the device has an oscillation frequency adjustment, this paragraph gives the range of such adjustment, from minimum to maximum.

A higher frequency (with the same amplitude — see below) improves overall performance, especially when working with hard, stubborn materials, and also contributes to efficiency in delicate finishing (such as polishing). In turn, a lower frequency reduces the likelihood of making a mistake by removing an excessive amount of material. There are also more specific points related to this parameter; them, as well as recommendations for choosing the frequency for different jobs, materials and types of sanding sheets, can be found in special sources. Here, we note that individual sanding sheets may have their own limitations or recommendations regarding the operating frequency.

The amplitude of oscillations made during the operation of the nozzle of an eccentric, vibration or delta grinding type machine (see above). Along with the frequency (see above), it is one of the most important indicators of such machines. Higher amplitude provides more intensive processing, which has a positive effect on performance; on the other hand, for delicate work, it is desirable to have a small oscillation amplitude(less than 2 mm).

The method of fastening the sanding sheet, provided for in a grinder with a vibrational principle of operation (vibration, delta sanding, multifunctional — see "Type").

— Clamps. Usually, this option provides a pair of clips located in the front and back of the sole. It can only be implemented in rectangular soles — for triangular soles used in delta grinding models, such devices are not suitable. Clips are somewhat less convenient than hook-and-loop, they require both more steps to secure the sheet, and more attention during these steps. On the other hand, this type of fastening is much more reliable than Hook-and-loop, it perfectly fixes the sheets and can be used even in the most powerful machines that work with high loads. In addition, compared to Hook-and-loop, clips are as versatile as possible (from the inside, the sanding sheet can have any surface — the main thing is that it fits in size) and more durable (practically do not lose their properties over time). And thanks to the durable materials that are usually used in the design, the likelihood of breakage of such a latch is minimal. Therefore, it is this option that is used in the vast majority of classic vibration machines — with rectangular soles.

— Hook-and-loop. Fastening according to the principle of a classic Hook-and-loop fastener: the sole has a surface with a set of microscopic hooks, and the underside of the sanding sheet is made of felt, for the fibers of which the hooks are hooked. Th...e main advantage of this option is that it has no restrictions on the form. So it is Hook-and-loop that is used in all modern delta sanders and multifunctional models (see "Type"), although in the second case they can be combined with clips. In addition, “sticking” and “unsticking” sheets on such a sole is easier and faster than changing nozzles in clamps. On the other hand, the reliability of fixation is somewhat lower than that of clamps; and over time, the effectiveness of Hook-and-loop can be further reduced due to wear on the hooks (the felt surface of sanding sheets also wears out a lot, but the working side of the sheet usually becomes unusable much earlier than the fastening one). In addition, this method of fastening is only suitable for a certain type of sheets — with a reverse surface for Hook-and-loop. In light of all this, this option is extremely rare in vibratory machines with rectangular soles — more often a combination with clamps is used, and most of these models use only clamps. Although in some situations, Hook-and-loop may be the best option for such a tool — for example, if high loads are not expected, and it is desirable to change the sheets without unnecessary delays.

— Hook-and-loop and clips. A combination of both options described above in one tool. The specific features of this combination directly depend on the type of grinder. So, in multifunctional models, different types of latches are usually provided on different removable soles: clips on a rectangular one, Hook-and-loop on a “delta”. Thus, each version of the working surface uses the method of fastening that is optimally suitable for it. And in vibration models, this design makes the machine as versatile as possible, allowing you to use sheets with it for both Hook-and-loop and clips.

Approximate noise level generated by the grinder during operation. Note that this indicator is quite approximate, because. actual "loudness" can vary markedly depending on the type and shape of the material being processed, the surface it is placed on, and other circumstances. In addition, different manufacturers may use different measurement methods. Nevertheless, this indicator makes it possible to assess how comfortable this or that model is in operation and whether special hearing protection is required.

The most “quiet” modern grinders give out about 65 dB — this is comparable to loud speech at a distance of 1 m; in the loudest, the noise level reaches 107 dB — this is the volume of an industrial workshop.

The length of the network cable can tell you how far from the outlet you can operate the device. Therefore, for domestic use, it is more relevant to choose models with a short cord, for construction work or use in production, in the garage a longer cable is better.