The difference between a grinding machine and a polishing machine

angle grinder and grinder. how they differ

angle grinder is the colloquial name for a power tool designed for abrasive processing of metal or other types of material.

The most important parameter when choosing an angle grinder is the disc size. The diameter of the disc determines the depth to which the device will cut the material. Also, do not forget that during operation, the disc is gradually erased and becomes smaller, thereby reducing the cutting depth.

Types of grinders

Belt sander. It is a tool where surface grinding is carried out unidirectionally, using a sanding cloth-belt, which is located on the rollers provided for rotation. This type of tool is suitable for polishing large surfaces.

Belt sander

Vibration sander. This type of machine is also called a surface grinder. It is a flat-bottomed instrument, hence the name. The surface is sanded using the reciprocating motion of the sandpaper. It is this action that is vibrational in nature. This type of machine also has vacuum cleaners for collecting construction dust.

Vibration sander

To work on ledges and corners, there is another type of vibration-type machines, this is a delta sander. The sole of this type of tool has a triangular shape, which allows you to work in hard-to-reach places.

Eccentric sander. This variety is commonly called orbital. The name, again, was formed from the appearance of the sanding sole. It resembles an orbit or, more simply, a circle.

Eccentric sander

Angle grinder. This type of machine rotates on its own axis. In addition to grinding, the angle grinder can cut metal, concrete and other materials.

Angle grinder

Polishing sander. The function of this tool is to polish metal and painted surfaces.

Polishing sander

Brush sander. The brush performs the functions of a grinder, rotating along its axis.

Brush sander

How to choose a sander?

Before proceeding with the purchase, you need to decide what specific device you need and what functions it should perform. The tape machine is designed to work in place of a planer. That is, the work of the tool is a rough roughing of paint and leveling the surface. For vibration, work on wood, plastic and metal is more common. Such a machine produces high-quality cleaning and polishing of the material. The orbital sander is designed to work with convex and curved surfaces. Thus, before purchasing this kind of tool, it is important to decide on what surface you will work on and what requirements the electrical appliance must meet.


A sander is a type of power tool for grinding and polishing surfaces of various materials, such as plastic, metal, wood.

Many types of grinders have the function of collecting sawdust, shavings, in a word, waste from the work performed. The vacuum cleaner can be either built-in or additionally connected.

Popular functions of angle grinder

  • Function “Soft start”. Devices that have this function are very convenient to use, due to the fact that the device starts to work at lower speeds, gradually gaining power.
  • Balancing. This feature is present only on the highest quality models.
  • The very shutdown of the brushes. This function is also only present on high quality devices. The brushes automatically turn off in the event of a power outage.

angle grinder in action

Comparative analysis of electrical appliances

As you can see from the above description of electrical appliances, the functions of these tools are 98% identical. Both devices are used for cutting, grinding and polishing materials from metal, wood, plastic and other materials.

Sanders have a wider range of separation of work areas (flat surface, angular). Also, many models have a vacuum cleaner function, which is not the case for an angle grinder.

Often, an angle grinder is used as a tool for cutting various materials, and a grinder is more intended for cleaning surfaces and subsequent polishing.

Inrush current limitation

The result of the work of the grinder should be a flat and smooth surface. But from the moment of launch until the start of work, the master does not always have time to adjust and make the necessary effort. As a result, the surface can be damaged, leaving unwanted grooves that will have to be sanded down. Therefore, many manufacturers equip their grinders with a soft start system. This approach is justified, especially if the eccentric wood sander. It’s all about the vibration that occurs immediately after turning on the machine. The presence of a soft start allows the ESM to gradually reach operating speeds and adapt to them for the master.

difference, grinding, machine, polishing


Creating the perfect surface for varnish or paint is impossible without a sander. Today for these purposes on the market you can find several different types of grinders, each of which is good in its own way. So, for example, even a high-quality and expensive belt sander will not be able to provide an ideal surface for varnishing or staining, unlike an eccentric one, which was created for this very purpose. There are no particular difficulties in how to choose an eccentric sander, even despite the huge assortment from various brands. The main thing is, before choosing an eccentric type grinder, determine for yourself what it should be in terms of basic parameters and additional functions.

For those who are going to perform surface grinding with an eccentric sander for the first time, the following should be explained. The eccentric sander is designed for polishing, coarse and fine sanding. In practice, in most cases, it is used only for polishing and fine processing with further varnishing or painting the surface. Such a narrow focus of the machine is due to the peculiarity of its work. The principle of operation is a reciprocating circular motion of the grinding wheel, which achieves high-quality processing.

EShM type

For the operation of ESM, various energy sources are used, depending on this, there are several types of eccentric grinders. It can be an electric machine powered by the mains or a battery, or it can be a sander that uses compressed air. This variety allows the use of ESM both where there is electricity and where it is not. Choosing this or that option, it is necessary to clearly understand why and where the ESM will be used.

If everything is more or less clear with electric grinders, then a little should be said about pneumatic. The eccentric pneumatic grinding machine is mainly used on an industrial scale, since it requires the installation of additional equipment in the form of a compressor or compressed air cylinders. These ESHM perfectly serve in the garage, service station or in the workshop for the production of furniture. Their main advantages are their low weight, it is only from 600 g to 1000 g. As well as a small number of moving parts. Since, using compressed air, the need for an electric motor has disappeared, there are correspondingly fewer parts. This affected both weight and service life. In addition, the low weight allows for a longer and more comfortable use of the tool itself. One of the manufacturers of such ESM is Dynabrade, with its Dynorbital eccentric grinders.

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Additional functions of the eccentric sander

Unlike the characteristics of eccentric sanders described above, additional ones have a lesser effect on productivity and quality of work. But the presence of certain additional functions allows you to make your work more comfortable.

difference, grinding, machine, polishing

Today, manufacturers are trying to provide their ESM with useful functionality as much as possible. These functions include speed control, various options for dust collectors, the ability to connect to a vacuum cleaner or an adapter for it, a second handle, a starting current limitation (soft start), a pressure indicator. Let’s consider each of them in more detail, since some of these functions can play a decisive role when choosing.

The amplitude of the ESM vibrations

The next parameter that affects the quality of surface treatment and depends on the speed of rotation is the vibration amplitude or, as it is also called, the eccentric stroke of the grinding machine. As noted above, ESM performs reciprocating circular movements. And if the speed of rotation to a greater extent affects productivity, then the amplitude of movement of the sanding pad is responsible just for the quality of processing.

Basically, the amplitude of the oscillation and the speed of rotation are related. It is the combination of these two movements that allows high-quality sanding. There are models on the market with an amplitude of 2 mm to 5 mm. DWT grinders have the smallest amplitude. The presented photo demonstrates the movements of the grinding pad of an eccentric sander, it can be seen how, depending on the amplitude of the vibration, the quality of surface treatment changes.

Dished head polishing grinding machine. Bombe polisaj makinesi

Important! It should be noted that for some pneumatic ESM, reciprocating movements are created using special levers-nozzles. Depending on which arm is installed, this will be the diameter of the grinding orbit.

Speed ​​control

Today, almost any power tool has this function and ESHM is no exception. Even in pneumatic ESM there is a possibility of speed control, realized in the form of pressure levers. For eccentric sanders, the ability to adjust the speed makes it possible to use the tool for both coarse and fine grinding. Which, in turn, allows you to save on the purchase of several grinders.

EShM plate diameter

The performance of the eccentric sander, in addition to power, also depends on the diameter of the sanding pad. Everything is simple here. the large area of ​​the plate allows you to quickly process a large area at a time. The most common sizes are 125 mm and 150 mm. But you can also find non-standard sizes of 50 mm, 80 mm, 90 mm or 115 mm. Although the eccentric sander is designed to grind only flat surfaces, the small diameters of the sole plate allow fillet grinding.

Non-standard sizes of the sanding pad are rare. They are produced by only a few companies and among the entire range of eccentric grinders on the market you can find only a few copies. Rupes TA 50 and Metabo SXE 400 grinders are outstanding representatives of ESM with a small plate diameter.

When purchasing ESM, in many cases it is enough to look at the model name to determine the diameter of the plate. Most manufacturers indicate the size there. For example, an eccentric sander Interskol EShM-150 / 600E. Looking at the markings, you can immediately determine that the diameter of the plate is 150 mm, and the power of the machine is 600 watts. But it will not be superfluous to look into the passport or ask the seller. Since the Makita BO5031 eccentric sander does not contain such data in its name.


Dust collector option

The result of the work of the grinding machine is not only a flat and smooth surface, but a rather large amount of fine dust. Of course, the manufacturers took care of the availability of a dust collector for her. But everyone has his own and is not always convenient.

difference, grinding, machine, polishing

So, for example, Makita’s eccentric sander is equipped with three types of dust collectors. plastic, rag and paper. But Bosch grinders only with plastic dust collectors with the possibility of replacing them with a vacuum cleaner. When buying an ESM, you should always consider the option of a dust collector that will be convenient for everyone in particular. The dust collector itself, of course, does not affect the quality of work, but even when cleaning it, you don’t want to bother too much.

Reviews of the 7620 Rodcraft eccentric sander

This pneumatic eccentric sander costs 326 euros. According to the manufacturer, it is a dream for the body repair specialist. The equipment is convenient to use, insulated in all necessary places where the hand can touch. According to users, such a machine will be able to do everything from hard disks to soft ones with a good finish. The equipment can be used for perfect smoothing of surfaces. Consumers love that the tool has a swivel connection for dust extraction, and perhaps even without a vacuum hose. Thus, the user will be able to carry out grinding work autonomously using only one compressed air.

Straight Air Grinder Review: 7025RE Rodcraft

If you need a pneumatic sander, then you can pay attention to its direct version, which is represented by the above model. You will have to pay 230 euros for it, which, according to users, is an affordable cost. You can use this equipment in one of the options presented, for example, as equipment for working with both hands, as a tool for working in narrow and deep places, as well as a device for processing cylinders. The pneumatic straight grinder is equipped with noise mufflers, which increase the comfort of work. The equipment weighs only 1 kg, which eliminates operator’s hand fatigue. The maximum number of revolutions per minute is equivalent to 22,000. The air connection is made through a hose with a diameter of 1/4 “. In one minute, the machine will consume air in a volume of 490 to 600 liters. The power of the tool is 700 W.

Specifications of 7131 Rodcraft Angle Air Grinder

This pneumatic sander, priced at € 331, is a large flat head polisher with M14x2 spindle. The handle is equipped with a heat-insulating layer, and the device has a rear connection for exhaust air outlet. Considering the technical characteristics, it is worth highlighting the disc diameter, which is 178 mm. The pneumatic angle grinder has a power of 500 W. As for the maximum number of revolutions, this parameter is 2500 units per minute. When connecting, use a thread whose outlet diameter is 1/4 inch. The device will consume air in a volume of 525 liters per minute. This model weighs 2 kg and is capable of operating at an operating pressure of 6.3 bar. For connection it is necessary to prepare a hose with a diameter of 8 mm. If you choose a machine for carrying out a certain type of work, then it should be noted that the class of its operational load is 3.

Specifications of the JetaPro

This air sander j 1038b is an orbital equipment enclosed in an aluminum casing. The user can comfortably engage the soft grip. The maximum rotational speed is 11,000 rpm and the pressure is 6.3 bar. It is noteworthy that this machine has a low weight, which is equivalent to 0.96 kg. If necessary, you can adjust the number of revolutions by choosing the speed depending on the characteristics of the material being processed and the surface. Considering the technical characteristics, it is worth highlighting that the diameter of the sole is 150 mm, the orbital stroke is 5 mm. Additional functionality includes a speed controller and dust extraction. The diameter of the air inlet is F 1/4 “.

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Today, enterprises that are engaged in the field of repair, construction, automobile production and metallurgy cannot do without a pneumatic grinder. It is required to purchase high-quality equipment of this type when it becomes necessary to process ceramic, marble, metal, granite and other surfaces.

Review of the features of the polishing machine for cars “Caliber UPM-180E

On sale today there are also grinders for cars, as an example is the model “Caliber UPM-180E”, which is a tool for use in small industries and home workshops. The tool can be used for polishing a variety of surfaces and is ideal for finishing body polishing and applying anti-corrosion compound. This equipment weighs 3.2 kg, the number of revolutions can vary from 600 to 3000 per minute. If you purchase this device, you will have to give it a rest from time to time during operation, since the manufacturer did not include protection against engine overheating in the kit. Among other things, the tool does not have a soft start. The power of the device is 1200 W, which turns out to be enough to perform the corresponding tasks. Includes a polishing disc, two handle mounting screws, a side handle, and two brushes.

Scope of use

Today, this equipment is used for cutting pipes and profiles, cleaning seams, as well as chamfering. The pneumatic sander is used when it is necessary to polish the car body. Such equipment performs a fairly wide range of tasks, and the classification of devices is very diverse.

Main varieties

If you want to purchase a pneumatic grinder, you should pay attention to three main types of such equipment, each of which is used to perform a kind of task. For example, a radial machine, which is also called a straight line, is used in cases where it is necessary to clean up welds, casting and other areas on the periphery of the surface to be treated. Most often, such devices are used during assembly and assembly operations. A pneumatic sander can also be angular, the cost of such equipment is quite affordable, you can find a huge number of models of angle options in a wide range on sale. This is due to the fact that with this equipment you can process almost all types of surfaces. This equipment can be equipped with a disc, an abrasive wheel, a metal brush, a sandpaper, as well as a dust extraction device. Another type is the orbital machine, which is different in performance, but easy to use. A velcro emery wheel acts as a working surface. A similar pneumatic sander can grind, polish, grind metal, wood and composite parts.

Polishing machines: types and tips for their use

It is not enough to make or repair many products or surfaces. It is imperative that you also give them a characteristic shiny look, polish. For this purpose, special devices are often used.

Features of the

The polishing machine can be used in a wide variety of fields. In particular, this device is used for finishing and improving the appearance of surfaces. The wide functionality of the tool is provided by changing nozzles and pastes. Tasks such as:

  • making a mirror or window glass shine;
  • improving the appearance of the car;

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Regardless of what kind of task is being solved, the polishing machine has a fairly typical structure:

  • body;
  • drive mechanism;
  • a pair of handles;
  • removable polishing wheel.

The appearance of such a device is similar to an angle grinder. However, the big difference is the use of completely different discs. It is natural that with an increase in the size of the working part, the processed area also increases. Also important characteristics of polishing machines are the grain size of the installed discs and the total power of the device. As the technical characteristics increase, so does the price.

Fixtures and spare parts

Regardless of the specific model of the polishing machine, its auxiliary equipment plays an important role. Among the nozzles, the bag stands out for its role. It allows you to collect as much debris, dust and waste as possible. As a result, the work is done as cleanly as possible.

Adhesive backing pads allow the sanding discs to be attached to the holders. Special flexible shafts help to work in hard-to-reach places. For the grinding itself, brushes or rollers made of nylon, metal and special composites are used. Polishers are supplied with main and auxiliary handles. But when choosing such components, you must carefully check so that they facilitate the work, and do not complicate it.

The sole for a vibration machine, as already mentioned, can be made in the form of a triangle or rectangle. The first type manifests itself better in a confined space, the second. in cases where it is necessary to process the maximum area. If the initial power cord is short, you will have to use an extension cord continuously. Of course, all spare parts and auxiliary components must be purchased only from official manufacturers.

Subtleties of choice

To choose the right polishing machine, you need to pay attention, first of all, to the power. This figure can vary from 0.8 to 2.5 kW. You should also take into account the pace with which the disc is spinning. The maximum value is 10 thousand revolutions per minute.

difference, grinding, machine, polishing

Important: you should buy only polishing machines with a speed regulator. Thanks to it, the selection of the operating mode according to the surface features is ensured.

It is advisable for inexperienced and inexperienced users to give preference to machines with automatic adjustment. Such a tool allows you to polish anything without fear of damage. But it is still worth practicing on old, obviously unnecessary, parts and surfaces. Battery-powered systems are more mobile than plug-in systems.

According to the type of drive, it is customary to distinguish pneumatic and electric polishing machines. The good thing about the pneumatic design is that the compressor drive does not require power consumption. In addition, such a device is the most stable and does not impose special requirements during operation. However, electric devices have an important advantage. increased mobility (due to the lack of binding to the air supply hoses). Removable rechargeable batteries allow you to use the device even where there is no stable power supply.

Attention should be paid to eccentric (orbital) polishing machines. experts consider such devices to be the most productive. The ability to work with a wide variety of surfaces is also very important. The orbital grinding and polishing system is equipped with a round-shaped platform. The grinding parts are fixed on this “support plate”. Working plates are made from:

  • fleece;
  • sponges;
  • felt;
  • corundum;
  • fur and other raw materials.

To fix the sanding block, both Velcro and a clamp can be used. The first method is appreciated for its convenience, and the other. for its economy. It is worth remembering that eccentric machines generate a significant amount of dust. Therefore, some manufacturers equip their products with channels through which it will be diverted. The main function of the sole is fine sanding (produced by rotational movements), and the auxiliary back-and-forth processing helps to improve the result.

The eccentric sander is available in different power levels, ranging from 150W to 1000W. For the simplest manipulations, you can limit yourself to low-power devices. no more than 400 watts. intensive work of the motor is needed only for coarse grinding of hard materials. Some devices are capable of delivering power over 2000 W, however, these models can only work in “wet” mode.

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In most cases, eccentric polishers are equipped with 125 mm discs. This solution is distinguished by the most rational vibration amplitude during finishing. However, the most serious work is successfully performed only with devices that allow the use of circles with a diameter of up to 215 mm.

Eccentric polishing systems are characterized by a wide range of applications. They work as efficiently as vibration complexes. In terms of power, the orbital polishing machine is comparable to belt mechanisms. It is important that it can also grind the treated surfaces. When selecting eccentric devices, one must not forget about the difference between household and professional models.

The versions used at home are mostly for wood polishing. As a rule, these are relatively low-power systems, capable of operating only with frequent interruptions. If it is firmly known that you will have to process metal and stone, you should give preference to the professional versions. These eccentric polishers are very heavy. But they can act for a very long time, while stably saving the working resource.

Floor grinding and polishing machines can efficiently process concrete and natural stone.

High-quality devices of this format are capable of:

  • align the base;
  • prepare it for finishing;
  • sand the surface to perfect condition;
  • to compact and harden the treated layer.

Attention: floor polishing becomes effective only when the device is supplemented with an industrial vacuum cleaner. Otherwise, everything around will be very heavily covered with dust.

When preparing to sand the floor, consider the grain size and mechanical strength of the diamond tool. When grinding, increased pressure on the surface to be treated is of great importance. Therefore, a more valuable option turns out to be cars that can be weighted with additional loads.

High quality grinding and polishing machines (including the Hodman brand) are equipped with planetary gearboxes and high-powered motors. Good mechanisms use chrome-plated steel tool holders. These holders must be fastened so that the movement occurs smoothly and quickly, even on uneven surfaces. This condition significantly increases the controllability of the machine.

Manual rotary mechanisms are used for polishing cars. Along with them, orbital systems can be used. The difference between them is the number of rotation axes (1 and 2, respectively). The lines of leading companies include both rotary and circular models. Each variety is good for its specific task.

Rotary apparatus is better than orbital one:

  • by performance level;
  • by a variety of substrate diameters;
  • on the maneuverability of the working part;
  • to save the efforts of the builder;
  • by noise level;
  • joint safety;
  • by the duration of operation.

It should be borne in mind that rotor systems have a rather low performance. This is why they generate less heat. The risk of damage to the varnish is also reduced. The appearance of “holographic” defects is almost excluded. Such a tool is great for soft polishing, however, it hardly helps to polish hard varnishes.

With all the importance of polishing a car, a few more words must be said about woodworking machines. Such devices have various applications. Some options help level out irregularities, while others are for finishing.

Important: Do not try to use angle grinders and belt machines for sanding wood. Then the surface will be too rough.

The wood is processed with eccentric machines. Despite their lightness and lack of special noise, they perfectly help to process curved areas, as well as profiled surfaces. The corners of the discs can easily be taken into the recesses and notches. However, at the same time, the tool can process a large block of wood in a short time.

Sometimes wood is polished and sanded with vibration systems. They are equipped with triangular or rectangular soles. Vibrating mechanisms assist in finishing. However, the performance of such devices is unreasonably low. In addition, a vibrating machine, even a triangular one, cannot work close to a wall or other obstacle.

The stone polishing and grinding tool invariably has working parts with diamond particles. For full processing, a whole set of discs with grains of various fractions is required. When selecting tools, pay attention to:

  • the color of the processed stone;
  • working part resource;
  • the amount of work;
  • efficiency, regularity and intensity of manipulations.

For working on concrete, those tools that are intended for manipulating natural stone are not suitable. Specialized fixtures can give the concrete surface perfect smoothness and increase its strength. At the same time, the permeability of the material to water decreases. Despite all the differences between specific models, the designs are pretty close. The rotating assembly is complemented by an abrasive element capable of removing the top layer of artificial stone.

Using polishers and grinders, you can:

  • make fresh concrete screed smoother;
  • smooth out the mass for finishing;
  • remove the cracked, rapidly decaying layer;
  • get rid of minor deformations;
  • increase adhesion for subsequent coating with paints and varnishes.

Rating of the best models

Summing up the review of the varieties of polishing and grinding technology, we can confidently say that they are very diverse. Still, there are a number of models that deserve close attention. Among the inexpensive versions, it is worth mentioning the Sturm AG1014P. This device, although marked with the logo of the German brand, is assembled in China. The designers were able to create an excellent mechanism capable of removing dirt and unnecessary coating, as well as artificially aging wood.

An electric motor with a power of 1400 W rotates at a speed of up to 3000 turns per minute. The total weight of the tool is only 3.35 kg. Options for soft start and latching of the start key are provided. The rotational speed in the loaded mode is maintained at a stable level. advanced (professional) option. Bosch GSI 14 CE.

A significant amount of money will need to be paid for the Makita BO6040. With this apparatus, you can remove rust and polish various flat surfaces. BO6040 is considered the ideal option for car paintwork. The determination of the number of vibrations and the rate of rotation of the shaft is carried out using an electronic system. Thanks to the smooth start-up, the processing is carried out in a gentle manner.

Usage tips

You can use a polishing machine for processing car bodies only after applying a special polish to the surface. In terms of chemical composition, this drug is quite complex. Getting ready for work, you need to prepare a couple of polishing wheels: one for rough, and the other for subtle effects. A small amount of paste is applied to the discs. Therefore, it is impossible to process large areas in one step.

The speed during rough processing should be minimal, and as the work approaches the logical end, it increases. An even distribution of the polish is achieved if the work is carried out using the “cross” method. initially horizontally and then vertically. The approach to wood polishing should be different. To get a good result, you should carefully study the features of a particular machine and the manufacturer’s recommendations. You should also take into account the characteristics of a particular type of wood.