Orbital Or Random Orbital Sander Which Is Better?

Belt sander

This is an electric sander

, the working tool of which is a sandpaper tape glued in the form of a ring. The tape is put on a pair of rotating rollers, one of which is driving, and moves along a flat pressure table located at the bottom of the unit.

A belt sander usually has a high speed abrasive element and high power. With this unit you can:

• easily and quickly remove a layer of wood of a few millimeters;
• align the height of glued wooden blanks, for example, when making doors;
• trim the edge of a part or round the corners of a workpiece;
• remove old paint or varnish coating, both on wooden and metal surfaces;
• clean metal from rust.

It is necessary to take into account the fact that after processing wood or metal with a CMM belt, small longitudinal scratches remain on the surface. To eliminate them, you will have to use an orbital or surface grinding (vibrating) CMM.

Where is it used?

The vibrating surface grinding machine is used in the workshop or during repairs and restoration of surfaces. During its operation, the moving platform comes into contact with the material, removing the top layer from it. The tool grinds materials with different levels of hardness and strength. Artificial and natural stones, polymers, wood, and metal are susceptible to impact, ensuring the removal of plaque and contaminants (carbon deposits, rust, scale). On the farm, the use of vibrating PMs is quite diverse.

Using them you can create the following actions:

• achieve the desired evenness and smoothness of the wood surface during restoration and repair of furniture;

• renew floors whose coating has partially peeled off;

• clean soot from household utensils used in food preparation;

• prepare walls, ceilings, window sills, stairs for finishing.

This is only a small part of the jobs that modern grinding tools can successfully handle.

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What are the types of grinding machines?

A grinding machine (MG) is an indispensable tool when performing various types of finishing work: polishing and grinding metal, wood, concrete, stone and other surfaces. Therefore, it is not difficult to guess that the choice of a grinder is made taking into account the types of work that are supposed to be performed in each specific case. Existing types of grinding machines allow you to level out unevenness in various materials, eliminate differences in height, and perform rough and fine grinding of surfaces. They differ not only in their design, but also in their operating principle.

Eccentric (orbital) devices

An orbital sander differs from other types of grinding machines in that it works like a regular vibratory sander

, only with circular movements of the sole.

Due to the rotation of the working platform, a certain layer of material is removed, and vibration grinds and cleans the surface being treated. The depth of processing is adjusted by the pressing force on the tool. The equipment is attached to the sole of the unit using Velcro.

An eccentric sander can be either electric or pneumatic. An eccentric pneumatic sander is used mainly in production and has its advantages over electric tools.

• Since this circular CMM does not have an electric drive, its weight is significantly less.
• Due to the light weight of the tool, it is used for leveling walls and ceilings.
• Due to the lack of an engine, the unit has a minimum number of parts that can fail.
• The grinder can be used in areas with a high risk of explosion, where the use of power tools is prohibited.

Eccentric sanders win first place among all units designed for grinding materials, thanks to the highest quality of surface treatment. Therefore, “orbitals” are mainly used for fine grinding and polishing. They are used to process plastic and metal surfaces, perform grinding and polishing work on wood, and polish varnished surfaces. They are also often used in car repair shops to prepare car bodies for painting and to polish the car after painting.

For standard polishing and grinding, “orbitals” with an eccentric stroke amplitude of 5 mm are used. For cars that require high quality polishing, it is better

choose a device with an amplitude of 3 mm.

Classification of tools

In stores you can find grinding machines designed for household or professional needs. Each type has its own characteristics, which it is advisable to know about before purchasing.

Household

A household tool is chosen if you have to work with it irregularly. On average, CMMs are designed to operate for 20 hours per month from 220 V, which is much less when compared with professional samples.

Every 15 minutes of working with a household grinder, you must stop for 10-15 minutes, otherwise there is a risk of damaging the engine.

Attention! Manufacturers do not recommend working with the device for more than 3 hours during the day. If you need more, you will have to abandon the household device in favor of a more serious one.

The advantages of a household unit are its affordable price and ease of operation.

Professional

This type of tool is designed to work continuously for a long time. Typically, professional grinding machines are used in production. They are much more reliable than household ones because they are made from higher quality materials.

The equipment is designed for multi-shift work in intensive mode. The devices are quite large, since a more powerful motor is located inside the case.

When developing a grinding machine for professional use, not only production requirements are taken into account, but also criteria such as convenience and safety. Therefore, manufacturers produce equipment that creates a minimum of vibration.

Deltoid sanders

This is a separate class of vibrating CMMs, since their main difference is the deltoid sole. The delta-shaped grinder is popularly called the “iron”.

Some hand grinders of this type have a rotating work platform. In such units, the worn sandpaper angle can be changed by simply turning the sole of the unit.

Due to its miniature size, the “iron” has good maneuverability and is used for processing complex surfaces, for example, for body repairs.

What are these devices?

Hand grinders are compact and lightweight analogues of industrial designs. All of them process surfaces with an abrasive material - sandpaper. There are different options for using this material, and corresponding tools are made for each of them.

They have different designs designed to perform specific tasks:

Mosaic sanders

The mosaic grinding machine is used for processing mosaic and concrete monolithic floors, as well as stone coverings. Using this technique you can:

• level out various sagging and eliminate floor defects;
• level floors;
• impart a certain degree of roughness to the surface before covering it with various decorative and protective compounds;
• polish large areas of concrete surfaces.

As equipment for concrete, mosaic grinding machines use special cutters - Frankfurt cutters. Floor mosaics are also polished with these cutters.

Polishing machines

Polishing machines are mainly used for grinding (polishing) car bodies. In appearance, a grinding polishing machine is very similar to a regular grinder, but differs from an angle grinder in the following ways.

• The handle is located on top of the body, that is, parallel to the working tool.
• The unit has a low minimum spindle speed (from 800 rpm), which is very important for polishing work. For comparison, for an angle grinder this figure can be within 2800 rpm.
• There is a function to keep the speed at the same level even under load.
• Polishing machines are always produced with speed control and soft start.

Polishing grinders can also be battery-powered.

You should know that a cordless grinder can only work effectively for 20-30 minutes, after which it needs to be recharged.

Planetary grinders

This type of grinder is used for polishing and grinding stone surfaces, for example, in the manufacture of fireplaces, window sills, countertops and other products made from this material. The planetary grinding machine consists of an electric drive and a planetary type grinding base.

This device uses flexible diamond-coated grinding discs as equipment. The unit is equipped with nozzles for supplying water cooling to the treatment area and has a connection pipe for connecting to a vacuum cleaner. The latter is connected to the CMM to remove stone dust during “dry” grinding of the material.

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Applications for eccentric sanders

• fine sanding of wood, plastic and metal
• polishing paintwork

Based on the listed capabilities, ESMs are used in the repair and manufacture of furniture, finishing work, body work during car repairs

The disadvantages of ESM include the inability to process corners and relief surfaces. You should not try to get the edge of the sanding disc, for example, into the recess of a door panel - the edge of the sanding disc can leave deep scratches on the wood. If you need to machine small parts and complex surfaces, it may be better to choose one of the engraving machines or renovators with appropriate attachments.

Surface grinding (vibrating) machines

If we take into account the cleanliness of the processing of parts, then surface grinders occupy an intermediate position between belt and orbital ones. With their help, they carry out finishing grinding of flat surfaces made of a wide variety of materials - plastic, wood, stone, metal... Thanks to the relatively large working plane, the PSM is suitable for working with serious quadrature. The secret to the popularity of vibrating sanders lies in their moderate cost, the availability of equipment elements, and the absence of dead processing zones (the flat out-mounted sole easily handles corners).

The main working body of a surface grinder is a plate, which makes frequent reciprocating movements with a small amplitude. The motor in such machines is located vertically, which makes it possible, using the “eccentric-counterweight” tandem, to convert the rotational movements of the shaft into translational movements of the platform.

Most vibrating grinders traditionally boast a motor power of 150–300 W; they are quite maneuverable, moderately light and compact. This level of power plant is almost always sufficient. However, such unanimity among manufacturers would be, at least, strange - there are models with a power of up to 600 W (Makita 9046). They are, of course, heavier and larger, but can work at low speeds for a long time without overheating.

Choosing a grinder | Which one to choose and what are the differences?

Makita 9046

The most important indicator of the PSM is the amplitude of the sole stroke. It may vary in different models, although it is invariably a relatively small value. On average for the class, the platform moves by 1–3 mm; in more mobile models, figures of 5–6 mm may appear (Festool RS 100). A larger amplitude helps to polish the surface faster, but such processing will also be rougher.

Another nuance is the frequency of the sole stroke. At high speed the machine will quickly remove a relatively thicker layer, while at lower speed it is easier to achieve a precise finish sanding. Some manufacturers make the frequency of movement of the platform variable, exceeding 20,000 strokes per minute (Bosch GSS 280 AE L-BOXX), which allows you to adapt to the processing of different types of materials and the characteristics of specific surfaces.

Bosch GSS 280 AVE

When choosing a vibrating sander, special attention must be paid to the platform. With its dimensions, everything is quite simple, there are two options: a kind of “standard” and “mini” models - the plate area is about 100 mm 2 (Makita BO4557, Sparky MP 250). Toddlers are good for tight, tight spaces. Obviously, the sole must be of high quality, perfectly flat, with clear geometric shapes. Budget machines are equipped with a platform made of steel or high-strength plastic, while more expensive analogues are equipped with cast platforms made of aluminum or magnesium alloys (Festool RS 100). A good sole is characterized by precise balancing, which is easily determined by a low degree of vibration when operating without load (idling). It is also important what the pad is made of; the most suitable option is a porous polymer, it is better

than rubber, “holds” the plane.

Vibratory grinders with a delta-shaped platform are included in a separate class; they are popularly called “irons” (Hitachi SV12SH, Makita BO4565). Due to their miniature size and good maneuverability, they are used for processing objects with small parts and complex surfaces, such as furniture, carpentry, staircase elements, and car body. Their triangular platforms are rotary - you can continue to work unevenly “eaten” by a petal of sandpaper (Festool Deltex DX 93E) or removable (with quick installation of another type of platform - for concave/convex surfaces, for structuring, polishing, rubbing).

Festool Deltex DX 93E

Emery can be attached to the site in different ways. It is more convenient when the paper is secured with Velcro, but special equipment is relatively expensive. The option with spring-loaded clamps is somewhat more complicated, but you can use inexpensive sanding paper that you cut yourself (you just need to make holes in the right places for dust removal).

The fight against fine dust, which inevitably forms when using a grinder, poses many challenges for developers. They have to work hard to protect all mechanisms. In this case, special motor sealing, protected bearings and switches, an impenetrable housing, and a channel system with forced dust extraction are used. To ensure that dust is removed from the work area and does not saturate the air, it is directed into a collection bag or filter; in most cases, a vacuum cleaner can be connected to the nozzle - this is the most effective method of protection.

Tips for use

You can use a polishing machine to process car bodies only after applying a special polish to the surface. The chemical composition of this drug is quite complex. In preparation for work, you need to prepare a couple of polishing wheels: one for coarse, and the other for fine impact. A small amount of paste is applied to the discs. Therefore, it is impossible to process large areas in one go.

The speed during rough processing should be minimal, and as the work approaches its logical finale, it increases. Uniform distribution of polish is achieved if you work using the “cross” method - initially horizontally and then vertically. The approach to polishing wood 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.

We devoted previous articles to screwdrivers, angle grinders, chain saws, jigsaws, mixers, spray guns, miter saws, jackhammers, and hammer drills. Today, all our attention will be focused on the tool that uses sandpaper.

Sanding or aging a wooden part, removing paint and varnish, removing rust, grinding off burrs, rubbing putty, processing plastic, polishing stone - all this and much more can be done with modern grinding machines. So, we offer the slogan: “Choose a grinder with us, choose like us, choose better than us!”

Sanding: This process causes discomfort for many, even at the mere mention of it. What can I say, grinding is a monotonous, labor-intensive, painstaking, dusty, sometimes noisy, slightly harmful operation, but, unfortunately, inevitable. Modern requirements for finishing work have reached unprecedented heights; no one questions the fact that the surfaces must be perfectly even and smooth. Finishing high-tech coatings are increasingly striving for thin layers and only highlight the shortcomings of the base. Even enlarged sheet building materials with a ready-made decorative coating have to be joined, followed by caulking/puttying or sealing the seam, followed by sanding. Domestic builders, finishers and shop workers (of stone products, bulk polymers, metal) are slowly but surely getting used to new standards, previously unknown.

Fortunately, the hardware did not lag behind for long: the working people are helped to cope with the task at hand by highly specialized, relatively inexpensive tools - grinding machines, which we can no longer do without. Gone is the painfully familiar sandpaper, attached to a wooden block, or held in one’s hands. The leaders of capitalist production have produced many, many wonderful professional grinding devices designed for any occasion, without neglecting home craftsmen - those who like to create something with their own hands. Understanding the variety of grinders and making the right choice is actually not difficult, the main thing is to know what a particular tool is intended for, and also clearly understand what tasks you will set for the grinder.

It is customary to distinguish three main types of grinding machines: belt, eccentric (orbital), surface grinding (vibrating). They all have their own specialization and form a unique cascade of capabilities, ranging from fast rough processing to delicate finishing grinding. Many of those who are closely associated with grinding “on duty” have in their arsenal a full set of tools of this class. Belt sanders are the heavy artillery for removing large layers from large surfaces. PShMs are oriented towards finishing. And ESMs are capable of producing even better results, bordering on polishing, but, compared to vibrating machines, they have a different operating principle and a different filling.

— “Interskol” EShM-125/270E

.On the next line of the rating is an inexpensive eccentric grinder from the Russian EShM-125/270E. This is a kind of quintessence of a grinding machine. There are no additional features on it, except for the simplest one in the form of adjusting the speed - only bare functionality.

The power of the Interskol EShM-125/270E is 270 W, which provides a maximum rotation speed of 12,000 rpm, which is enough to effectively perform the direct grinding task. Fastening the sheet with Velcro. There is a built-in dust container for dust and waste. For its extremely low price, Interskol EShM-125/270E can be considered simply an excellent device.

Random orbital sanders

Random orbital sanders are considered the most effective and versatile tool for polishing and grinding surfaces. In industrial production and private use they show the best results in surface quality.

Polishing and grinding are possible thanks to a combination of rotational and eccentric movements of the soleplate. The sole rotates in orbit and simultaneously scrolls around its axis. This complex movement of the abrasive allows for efficient grinding with minimal imperfections.

The machine weighs from 1 to 3 kg, is equipped with a round sole with Velcro, to which an abrasive wheel on a felt basis is attached. The soles come in two sizes - diameter: 125 and 150 mm. Machines with a 125 mm soleplate are lighter, designed for smaller areas and for more delicate work than sanders with a 150 mm soleplate. Electric motors consume between 200 and 900 watts - more power means more performance. When installing the equipment, it is important that the holes on the sander sole coincide with the holes in the abrasive wheel, otherwise the dust removal process will be difficult.

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They are used for rough or fine grinding on large surfaces, for interlayer processing of materials and coatings, for polishing, processing large surfaces along and across the grain. Often machines of this type are used in carpentry and car painters. Using ESM, volumetric, profile and curved surfaces are processed. When working with an eccentric sander, it is unlikely to damage the workpiece: make abrasions, burn the material, or overdo it with the grinding depth. The noise and vibration levels are lower than other types of grinding machines.

The disadvantages are obvious: eccentric machines are not suitable for processing internal corners and recesses. Productivity is low compared to belt sanders.

Delta vibratory sanders

The peculiarity of this instrument is its compact, lightweight body - the instrument weighs up to 1 kg; delta-shaped sanding pad, which is why these machines are called “iron”. Electric motor power up to 300 W. Grinding in hard-to-reach places is carried out due to the fact that the triangular sole makes rapid vibrations with a small amplitude. The accessories (sanding sheets) for this tool are not sold everywhere and are more expensive than paper-based sanding belts or grinding wheels.

Using a delta sander, fine grinding of protrusions, blind corners, edges, profiles, cleaning of exposed glue, processing of objects with small parts and complex surfaces are performed.

The delta-shaped orbital sander is especially good in carpentry, furniture making, stairs, and automotive body work; it is used as a main tool or in addition to eccentric or orbital sanders.

Electric file

There are special-purpose belt sanders, so-called belt files or electric files. Often used for cleaning welds and grinding materials in hard-to-reach places. Only certain equipment with a width of 9 to 30 mm is suitable for electric files. Such belt sanders weigh much lighter than conventional ones - 1-2 kg.

— FESTOOL ETS EC 150/5A EQ

. And finally, the leader of the rating is the Festool ETS EC 150/5A EQ orbital sander. Its compact dimensions and light weight are combined with a good power of 400 W and provide rotation up to 10,000 rpm. The maximum disc diameter is 150 mm. First-class build quality, sanding pad brake and EC technology contribute to durability. The built-in vibration reduction system will protect your hands, and the dust collector will eliminate flying dust. The Festool ETS EC 150/5A EQ is a quality sander that can be used in any position, even on overhead surfaces, without straining yourself. The quality of grinding will always remain at the highest level. Everything in this device is thought out and functional: from the stabilization system to the geometry of the case. Choosing a sander is not the easiest task, and we hope that we could make it at least a little easier for you. Choose one of the proven tools, and then the risk of getting a pig in a poke instead of a reliable and effective tool will be minimized. And remember that the best sander is the one that suits your needs and fits your needs.

Rating of the best inexpensive grinding machines for car polishing

You can choose an electric grinder for car painting and polishing among inexpensive units. Cheap models are usually not suitable for service use, but they are quite convenient to use in the garage.

Bosch PSM Primo

The German grinding machine is small in size and light in weight. Equipped with a built-in dust microfiltration system, suitable for treating the most inaccessible areas of the car. The electrical device contains a container for collecting waste. The model operates quite quietly and does not cause irritation.

You can purchase a Bosch PSM Primo grinding unit from 4,600 rubles. Pros

• weight 600 g;
• does not make noise when used;
• prevents dust from flying around the room.

Minuses

• it is difficult to find replacement sandpaper;
• not suitable for large-scale work.

Makita BO3711

An inexpensive electric machine with smooth speed control and reliable abrasive fastening comes with a functional dust collector. Provides high-quality polishing of the car surface; the handles of the unit are rubberized and do not slip. The weight of the tool is 1.6 kg.

The price of the Makita BO3711 grinder starts from 4,500 rubles

pros

• convenient speed adjustment;
• fastening the sandpaper to the clamps;
• The cable is protected from abrasion.

Minuses

• no adapter for vacuum cleaner;
• The network cable is short.

Bort BWS-1000-125

A budget sanding machine with a power of 1000 W easily copes with any task of polishing a car body. It has a durable metal body, the power button is conveniently located on the handle. There is dust protection; the electric machine comes complete with a casing, a side support and a key for replacing the disk.

You can buy an electric grinding machine for a Bort car from 2,700 rubles

pros

• good power;
• universal disc size 125 mm;
• wide range of equipment.

Minuses

• vibrates slightly during operation;
• makes a lot of noise;
• The network cable is short.

— Bosch GEX 150 Turbo

.The second creation of the Germans from Bosch and the third place in the rating is the GEX 150 Turbo grinding machine. Its main advantage is the power of 600 W, which, together with a rotation speed of up to 6650 rpm, ensures efficient and high-quality grinding of various materials. There is a dust collector to which you can connect a vacuum cleaner and get rid of dust as you work. Bosch GEX 150 Turbo is one of the most powerful and productive grinders. Yes, not the lightest, but the weight plays into its favor, so together with the anti-vibration system, shaking is reduced to nothing. Yes, not the quietest, but quite ergonomic, pleasant to use, and most importantly - durable.

- Dewalt DWE6423

.

DWE6423 is an eccentric sander model from the American brand Dewalt. It can also be classified as a budget, but effective device. This sander produces 12000 rpm with 280 watts of power. The maximum disc diameter is 125 mm. There is a speed control, a dust collector and a speed stabilization system. Comfortable operation is facilitated by built-in vibration protection. At a low cost, one cannot fail to note the build quality of the Dewalt DWE6423, which gives a strong feeling of device reliability when handling it. The weight of the model is acceptable, the price is affordable, and the handle is comfortable - how much more is needed for comfortable work.

Our article will help you decide on the right model - How to choose an angle grinder for your home.

Pay attention to the parameters when choosing a grinder

It should be noted that both of these grinders mostly perform finishing work, and if you have the task of performing work on a large scale, then the wrong choice will bring you not only financial losses, but also wasted time.

Vibrating or eccentric sanders can have different purposes:

• For household use;
• Professional scope of application.

When choosing a grinder, you should pay attention to the following technical characteristics:

• Platform stroke amplitude. This is one of the main characteristics of grinding machines. Average vibration value. 2-3 mm. The higher the amplitude, the higher the performance of the grinder, but the grinding becomes much coarser. That is, if you need a grinder for primary processing, pay attention to models with high amplitude. For finishing purposes. on the contrary, machines with an amplitude of 2 mm and below;
• Sole size. PShM and EShM soles come in different sizes and shapes, although there are generally accepted standards. for eccentric diameters 122 and 150 mm, for PShM 187x90, 115x230, 114x105 mm. Models with small soles will help when working in hard-to-reach places;
• Speed ​​adjustment. Thanks to this function, you can customize the operation of the machine. primary or finishing processing, as well as choose the optimal speed for grinding a particular material. For example, if we are sanding soft wood or plywood, then it is recommended to choose medium speed, and if we are sanding hard wood. high;
• Power. The power consumption of machines can vary from 130 to 900 W. But, as a rule, for most work, a power of 200-300 W is quite enough, because such models are light and compact, easy to control, and work with them is more comfortable;
• Attaching sanding paper. Manufacturers have provided 2 types of fastening for a surface grinder: a clamp (similar to a regular latch with a spring, which is found on most household-grade sanders) and Velcro (less hassle with it, since you don’t have to cut the paper, it has a standard size, but the cost of such machines , as well as consumables, above).
• Additional handle. For PShM and EShM, the additional handle is either cast or removable. If it is removable, this reduces the size of the device and allows you to use the tool with one hand. This is convenient when sanding small parts.

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Subtleties of choice

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

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’s still worth practicing on old, obviously unnecessary parts and surfaces. Battery-powered systems are more portable than plug-in systems.

The following video will help you choose the right polishing machine.

Based on the type of drive, it is customary to distinguish pneumatic and electric polishing machines. The pneumatic design is good because the compressor drive does not require electricity consumption. In addition, such a device is the most stable and does not impose any special requirements during operation. However, electric devices have an important advantage - increased mobility (due to the lack of connection to the air supply hoses). And removable batteries allow you to use the device even where there is no stable power supply.

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

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

READ How An Orbital Sander Works

To secure the sanding block, either Velcro or a clamp can be used. The first method is valued for its convenience, and the other for its efficiency. It is worth remembering that eccentric machines emit a significant amount of dust. Therefore, some manufacturers equip their products with channels through which it will be discharged. The main function of the sole is fine grinding (produced by rotational movements), and auxiliary reciprocating processing helps improve the result.

The eccentric sander has different power levels - they range from 150 to 1000 W. For the simplest manipulations, you can limit yourself to low-power devices - no more than 400 W. More intensive motor operation is only needed for rough grinding of hard materials. Some devices are capable of delivering power in excess of 2000 W, however, such models can only operate in “wet” mode.

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

Eccentric polishing systems are distinguished by their wide range of applications. They work as efficiently as vibration complexes. The power of an orbital polisher is comparable to belt mechanisms. It is important that it can also grind the surfaces being processed. When selecting eccentric devices, we must not forget about the difference between household and professional models.

The versions used at home are mostly designed for polishing wood. Typically, these are relatively low-power systems that can only work with frequent breaks. If you know for sure that you will have to process metal and stone, you should give preference to the professional versions. Such eccentric polishing mechanisms are characterized by their large mass. But they can operate for a very long time, while consistently saving working resources.

Floor sanders and polishers can effectively process concrete and natural stone.

High-quality devices of this format are capable of:

• level the base;
• prepare it for finishing;
• sand the surface to perfection;
• compact and strengthen the treated layer.

When preparing to sand a floor, you should consider the grain size and mechanical strength of the diamond-coated tool. When grinding, increased pressure on the surface being processed is of great importance. Therefore, vehicles that can be weighed down with additional loads are a more valuable option.

High quality grinding and polishing machines (including the Hodman brand) are equipped with planetary gearboxes and high-power motors. Good mechanisms use chrome-plated steel tool holders. These holders must be fastened so that 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 own specific tasks.

A rotary device is better than an orbital one:

• by performance level;
• by the variety of substrate diameters;
• by the maneuverability of the working part;
• to save the builder's effort;
• by noise level;
• on safety for joints;
• by duration of operation.

It should be borne in mind that rotary systems are characterized by rather low productivity. This is why they produce less heat. The risk of damage to the varnish is also reduced. The appearance of “holographic” defects is almost excluded. A tool like this is great for soft polishing, however, it does little to polish hard varnishes.

Despite the importance of polishing a car, a few more words must be said about wood processing machines. Such devices have various areas of application. Some options help smooth out uneven areas, while others are intended for final processing.

Wood is processed with eccentric machines. Despite their lightness and the absence of much noise, they are excellent for processing curved areas, as well as profile surfaces. The corners of the discs easily fit into the recesses and notches. However, the tool can process large amounts of wood in a short time.

Sometimes wood is polished and sanded using vibration systems. They are equipped with soles of a triangular or rectangular configuration. Vibrating mechanisms help to achieve a fine finish. However, the productivity of such devices is unreasonably low. In addition, a vibrating machine, even a triangular one, cannot work close to a wall or other obstacle.

Polishing and grinding tools for stone invariably have working parts with diamond particles. For complete processing, a whole set of discs with grains of different fractions is required. When selecting tools, pay attention to:

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

Tools that are designed for manipulating natural stone are not suitable for working on concrete. Specialized devices can give the concrete surface an ideal 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 quite similar. The rotating unit is complemented by an abrasive element that can remove the top layer of artificial stone.

Using polishing and grinding machines you can:

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

Sander: vibrating or eccentric

expert in the category “Power tools”

To obtain an even and perfectly smooth surface when sanding, I always recommend that craftsmen use two sanders. One is for initial, rough stripping, the other is for final stripping.

If everything is clear with the initial processing. here you need to take a belt sander, then when bringing the surface to perfection you can use one of two types:

Vibratory (another name is surface grinding, or abbreviated as PShM);

• Eccentric (ESM, another name is orbital).

Both are designed for sanding substrates when completing work. Which of these cars is better

. Is the sander vibratory or eccentric? I will tell you today in this article.

You will learn what their main differences are, how their design determines the capabilities of each device, and what their strengths and weaknesses are.

The information presented will give you the necessary knowledge on how to sand surfaces of different shapes using these units, and which one will suit you best.

Design differences between the two machines

Both machines are capable of delicately sanding the surface with sandpaper. In fact, they do the same job, but there is a difference between them. They differ in both shape and operating principle. The surface of a PSM is often rectangular (but can be deltoid or square). And the eccentric one. the sole is round. Therefore, depending on the complexity of the grinding work and the shape of the workpiece, you choose a machine with a convenient sole shape. For example, steps or shelves can be easily sanded with a grinding machine; thanks to the angular sole, they can be reached into any corner.

The eccentric machine is used for working with both flat surfaces and radii, as well as wooden parts of various shapes. Orbital and eccentric sanders are used in construction workshops; in car repair shops they perform not only finishing work for sanding wood, but are also convenient for various types of finishing work. But still, their main purpose is to ideally prepare the surface for painting or give the part the required shape.

Essentially, these are two identical tools, but there are some differences. A surface (vibrating) sander can handle any surface: wood, plastic, metal, walls (plasterboard). But she does it a little rudely, unlike ESM. In turn, an orbital sander will perform this entire list of work more delicately due to the fact that it has an additional rotation function, which helps hide sanding marks.

Basic principles of grinding

These two types of grinders differ significantly in the grinding principle. First, let's review the vibrating tool. The mechanism of operation is quite simple; to clean the surface, reciprocating movements with an amplitude from 1-3 (low-power) to 5-8 mm (powerful) are used. This allows you to cope well with a metal surface or plastic, unlike ESM. However, PShM leaves marks on wood and is not suitable for opening with varnish, but only for coating with paint.

The principle of operation of an ESM is that with the help of a round sole, not only vibration occurs, but also rotation around its own axis. Thanks to this double movement, the ESM perfectly prepares the surface for varnishing. During operation, it leaves no sanding marks at all. Models of this type ideally create the effect of abrasive grinding. Widely used for furniture restoration or decoration.

General Features

• Most modern grinders are equipped with a dust removal system: a construction vacuum cleaner is connected through a special connection or the kit includes a dust collection bag. This makes the work process cleaner, the tool itself is better controlled, and the consumption of abrasive equipment is reduced.
• Based on the type of power supply, machines are divided into mains-powered and battery-powered. The advantages and disadvantages of cordless grinders are obvious - mobility and independence from the mains, but operating time is limited by battery charge.

Let's sum it up

Advantages of eccentric sanders:

Pros of vibration sanders:

• Effective sanding of wood, stone, primer, metal;
• There is a wide choice of sole sizes and shapes - rectangle or delta;
• It copes well with corner surfaces, does not leave unworn areas on the edges, close to the edging, in narrow places.

We count the following as disadvantages of PShM:

• The quality of grinding is not as high as that of an ESM. Often leaves scratches on wooden areas.

If we talk about surface cleaning, then for more delicate grinding it is better

select and use eccentric machines.
They better
in the finishing stage and are designed for perfect sanding.
Although their productivity is significantly lower than that of vibration ones. However, an orbital
tool is indispensable on volumetric surfaces with curved and profile parts.

It's better in a larger area

use a vibrating sander, as its power and performance are much
better
. If you need to process a surface with corners, then you cannot do without a vibrating machine. Thanks to the rectangular shape of the sole, corners and hard-to-reach places, as well as the edges of the product, are easily processed.

Sources:

https://vahatehnika.com/mashin/orbitalnaya-ili-ekstsentrikovaya-shlifmashinka-chto-luchshe.html https://storgom.ua/novosti/shlifmashinka-vibratsionnaya-ili-ekstsentrikovaya.html

Manufacturers rating

• Bosch. This brand is engaged in the production of electronic PSMs for carpentry experts. The range includes models with a platform measuring up to 92x182 mm, developing up to 22,000 rpm with a power of 300 W. Easy-to-change equipment is complemented here by the greatest convenience when performing narrow sanding of wood and plastic.

• DeWalt. This is a South American brand specializing in the production of professional surface grinders. The models are adapted for long-term work, including on a construction site or in large premises. They help achieve flawless smoothness without effort.

• Makita. This Japanese manufacturer presents a wide range of products, providing a very comfortable choice of PShM for different purposes. The machines are equipped with modern control systems, strong high-speed motors, and dust extractors. The set of equipment is one of the richest.

• Metabo. This German brand is mostly focused on producing eccentric models, but its range also includes surface grinding equipment. The ergonomic body, compact dimensions and adjustable intensity make it a good choice for amateurs and experts.

• Ryobi. This is a Japanese manufacturer that relies on innovation. The machines have a special non-slip coating on the handle and use a completely new dust removal system.

• "Fiolent". This is quite an exciting manufacturer, which has recently received Russian “registration”. Its model range includes heavy and massive machines for scraping floors and other work that requires long, continuous exposure to the surface of the material. The platform has a large power reserve, but there is no excessive vibration.

• "Interskol". This is a manufacturer that produces its products for the domestic market. The range of models includes technologically noteworthy solutions with built-in dust extractors, elements that dampen vibration and noise. Powerful vibratory sanders are equipped with soleplates or cast aluminum, which last a very long time. The kit includes a power button lock, which is irreplaceable for long-term continuous operation of the device.

• "Fiolent". This is quite an exciting manufacturer, which has recently received Russian “registration”. Its model range includes heavy and massive machines for scraping floors and other work that requires long, continuous exposure to the surface of the material. The platform has a large power reserve, but there is no excessive vibration.

How to choose a grinder. Types of grinders based on operating principle.

This carefully describes what types of grinders there are, and discusses the operating mechanism of each type.

Random orbital sanders

While introducing you to the principle of their operation, it is worth mentioning this type of sander that is used from time to time, such as orbital sanders. In orbital sanders, the circular working surface rotates around its own axis. But that's not great enough. The round working surface of eccentric machines, in addition to rotational ones, also performs oscillatory movements, combining orbital and non-rotational types of movement. Such a complex movement path allows for more uniform grinding of the curved-convex surface being processed with uniform use of abrasive. To put it another way, the scope of activity of eccentric sanders is very extensive. They cope well with various curved surfaces and are not good for cleaning, sanding, polishing wood, metal, plastic products, and additionally for particularly fine sanding.

Just like when using vibrating grinders, when selecting an eccentric grinder, it is necessary to note the amplitude of oscillations and not the power. The 1st varies from 3 to 7 mm. The next reason is from 170 to 750 W. The higher the speed of movement of the working surface, the faster the processing occurs and the rougher the grinding. More powerful machines have slightly higher performance. Just as in the case of a passage with vibrating machines, fastening of replaceable sheets to the sole of eccentric devices occurs using a clamp or Velcro.

The braking system, which prevents the disc with abrasive from spinning idle, will help to avoid unnecessary disadvantages of not scratching the surface being treated. It is also worth asking whether the machine is equipped with a speed controller. Low speeds are necessary for rough processing without sanding painted surfaces, high speeds are necessary for hard wood species without finishing work.

A small addition: there are two types of eccentric sanders. The first ones - with a handle for the palm, light, compact. 2nd - with a classic handle. If you have to do delicate delicate work, it is better to trust first. They will help polish the most inaccessible places on objects. But machines with a classic handle are excellent at processing large surfaces.

Used as a candidate for manual labor, a vibration grinding machine is a tool with a flat working platform on which special consumables are attached to perform operations to clean the surface and make it smooth. Affordable price, functionality and reliability make it a beautiful choice for the home workshop. The technical features of flat sanders for wood allow them to successfully handle large volumes of work, ensuring the highest quality of surface treatment of the material without significant time costs.