Can a polishing machine be used as an angle grinder

How to choose an “angle grinder” (angle grinder)?

Angle grinders or, as the people say, “angle grinder”. Specially designed for cutting hard metals and stone, roughing, cleaning, grinding surfaces, etc.

The working tool “angle grinder” is most often an abrasive disc for cutting or grinding a certain type of material. Cutting discs are much thinner than grinding wheels.

Each specific disc is designed for a strictly specific type of material. Failure to do so may result in loss of the disc and injury.

The maximum permissible size of the abrasive used is the first main characteristic of an angle grinder. These include:

  • maximum permissible diameter (D) and its thickness (b),
  • and also the connecting thread of the spindle (d).

As for the diameter of the disc, it is this characteristic that determines the functionality of your tool. The larger this value, the deeper you can make the cut.

The working surface of the disc is its edge, not the side surface. Therefore, it is recommended to make deep cuts in several passes.!

The next characteristic is the idling speed of the spindle. The key point in calculating the optimal spindle speed is the fact that the linear speed of the cutting tool surface at the point of contact with the workpiece surface should be close to 80 m / s (of course, relative to this workpiece). Therefore, the rotational speed of large-diameter discs is lower than that of their smaller counterparts (the logic is extremely simple: the higher the disc diameter, the longer the circumference, and the larger the long working surface of the tool the machined surface will come into contact with during one spindle revolution).

Many models of angle grinders, especially those belonging to the professional category, are equipped with a spindle speed control system. This is done for several reasons:

  • firstly, it is not at all necessary to use the disc with the maximum diameter in the “angle grinder”. For a smaller diameter, a higher rotation speed is required;
  • secondly, during operation, the disks are erased and, accordingly, a higher rotation speed is required;
  • thirdly, the “angle grinder” is also used for grinding and cleaning surfaces, and at high speeds, many processed materials begin to simply burn, which is undesirable.

Power consumption. This indicator is very closely related to the maximum diameter of the working tool, because a disc with large dimensions weighs more and experiences more significant loads. In addition, a more powerful tool is more durable, does not heat up as quickly, etc. Therefore, professional angle grinders designed for long-term work are more powerful than their non-professional counterparts.

Some features are associated with tool power and spindle speed

  • a range of angle grinder models are equipped with an inrush current limiting system or a soft start system. Due to the presence of this system, at the moment the tool is turned on, there is no significant inrush current (at least it does not exceed 16A), which makes it possible to connect it to a household power supply;
  • some advanced models of the “angle grinder” are equipped with a system for maintaining a constant speed of the disc (constant electronics), so that, regardless of the applied force, the working tool is in optimal working mode;
  • there is also a system for protecting the tool from switching (self-disconnecting brushes). This system is used in more advanced angle grinders. The essence of the process is as follows: if during operation there was a short-term disconnection of the supply voltage, and then the voltage appeared again, the angle grinder will not start working on its own. To continue working, you must turn it off (using the on / off button), and then turn it on again;
  • automatic disk balancing system. Its essence is as follows: in the process of work, a disc (especially a cutting disc) in most cases wears out unevenly (whoever worked himself knows). Because of this, the machine begins to vibrate, thereby making the work process even more difficult. To eliminate this inconvenience, some manufacturers have come up with an automatic disk balancing system. The principle of its operation is similar to the principle of operation of the vibration stabilization system of some washing machines (bearing with missing balls).

Now a few words about angle grinders in general. They are one-handed or two-handed. Both those and others can be equipped with an additional handle, which can be rearranged for ease of operation. The more possible options there are, the naturally better (and for the left-hander as well).

Ryobi Angle Grinder as a POLISHER?

If we talk about the handle, then in some models of the “angle grinder” special vibration-absorbing handles are used for more comfortable work. Some manufacturers, for the convenience of work, suggest not to rearrange the handle, but to turn the gearbox.

The disc is replaced, as a rule, using keys (they are attached to the tool).

Also, a number of models are completed or can be additionally equipped with a special nut that is screwed and unscrewed manually, that is, without additional tools (for example, the SDS quick-locking nut for BOSCH). In addition, for the convenience of replacing the disc, most of the current “angle grinders” have a spindle lock button.

To increase the safety of work, angle grinders are equipped with protective covers that can be adjusted like a handle, and in some models even without the use of an additional tool. To protect the “angle grinder” themselves from abrasive dust, the windings of their electric motors (armored windings and protective cord bandage of the armature) can be additionally protected.

Never start working with an angle grinder without protective goggles! The rotating speed of the working tool is very high! In addition, most manufacturers strongly recommend the use of special protective gloves and a helmet.

Above mentioned is the fact that there are professional and non-professional grade “angle grinder”. So, in addition to their visible differences in technical characteristics, professional angle grinders are also distinguished by the fact that, being designed for longer and harder work, their components are made from more durable, but, accordingly, more expensive materials.

Since the “angle grinder” can be safely attributed to the “unsafe” tool, in order to avoid accidental switching on, many models are equipped with a protection button against accidental switching on.

Angle Grinders Accessories

Rough and cut-off wheels. Rough and cut-off wheels can be used to separate workpieces easily, quickly and economically, as well as to grind. When working with a roughing wheel, the machining angle should be between 30 and 40 degrees. If the workpiece to be machined requires a flatter angle grinder, the grinding wheel must be ground from time to time to get the grinding edge on the workpiece again. Cut-off wheels are not recommended when working on wide sides of metal workpieces and when cutting swinging workpieces.

Grinding discs are economical in operation, have a wide range of processing of metal, wood, plastic and stone.

Cup grinding wheels made of hard metal can be used on small planes, remove all kinds of layers on plastics (fiberglass), adjust limestone or aerated concrete panels, remove thick layers of paint, etc.

Grinding belts for angle grinders. Velcro-bonded paper sanding discs and rubber backing fiber backing discs (heavy duty in heavy sanding work) are suitable for a wide range of materials: wood, varnish, metal and stone. Operating range. from fine to coarse sanding, peeling off scale and rust. They are especially effective in car repairs.

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Diamond cutting discs. Each type of these discs is intended for a strictly specific type of material: discs for granite. for very hard material (they get stuck in viscous), asphalt discs become dull in granite, and varieties for concrete are not suitable for limestone.

Helpful hint: flat cuts lead to quick material separation and increase tool life, deep cuts in one pass increase the working time, reduce the tool life, while the disc is exposed to significant overloads. For example, in practice, when cutting a concrete wall with a special diamond blade with a diameter of 230 mm, it is not recommended to go deeper than 20-25 mm in one pass. And the maximum allowable cutting depth for this circle. 60-65 mm. Deeper cuts are possible, but with the help of special devices, which can be attributed more to machine tools. In addition, it is strongly recommended to cut metal reinforcement in reinforced concrete with a special cutting disc for metal.

Types of diamond cutting discs:

  • type “concrete” cuts effortlessly on hard types of concrete, as well as on reinforced concrete;
  • the “granite” type cuts into superhard rock such as gneiss and granite;
  • type “asphalt”. best for handling difficult abrasive materials such as fresh concrete and asphalt;
  • type “building material”. for interchangeable use in the processing of fired brick and concrete.
polishing, machine, used, angle

Scorpio E (grinding)

Rotary-orbital model. No compressor is required to ensure normal operation. If you wish, you can connect a vacuum cleaner for dust extraction.

  • eccentric stroke is 3 mm;
  • circle with a diameter of 150 mm;
  • revolutions. 1000 per minute;
  • power is supplied from a 220 V network.

The model is the best option for machining planes with the deepest damage. The manufacturer does not recommend using for processing bumpers, pillars and openings.

Basic set: LH19, LHR21, LHR75, Skorpio E, TA50, Brid, LHR15 and Mille

The set considered in the past still did not have enough tools to effectively fully polish numerous openings, which creates an urgent need to add the TA50.

This allows the master in the future to provide the most comfortable conditions with deep damage to the paintwork in rather narrow places. However, this will require additional installation of a compressor.

As an impressive help, it’s worth adding a few more modifications. For example, the rotary LH19 with the available circle diameters of 135, 160 and 180 mm, respectively, allows not only to heat well, but also to effectively melt and at the same time hide existing deep scratches.

Planetary Mile is equipped with a circle with a diameter of 140 and 165 mm, respectively. A distinctive feature is the ability to cut paintwork, but without the possibility of heating, which automatically excludes the possibility of holograms formation.

What technical parameters should you pay attention to when choosing

When you need a polishing machine, how to choose is often a real problem. In this case, it becomes necessary to pay attention to numerous technical parameters, including:

  • circle diameter;
  • used type of rotation and speed.

It is advisable to consider separately for better understanding.

LK900 Mille

The best option for craftsmen with any work experience.

  • planetary model;
  • the eccentric stroke is inconsistent, varies within 3-5 mm;
  • circle diameter. 140 and 165 mm, respectively;
  • works from 220 V power supply.

The tool is able to cut varnish almost at the same level as the rotor, but there is no possibility of a hologram forming. The model is an excellent solution for those who need to process doors and various convex surfaces.

Tool weight is 3 kilograms.

How to choose a polishing machine

A polishing machine is an indispensable tool in everyday life, especially for those who live in a private house. To be satisfied with the purchased model, you need to know about the available features.

LHR21, LHR75, Skorpio E, Brid and LHR15

To the previous options considered, you can safely add a few more modifications. The LHR21 is equipped by the manufacturer with a circle with a diameter of 180 mm and an eccentric stroke of 21 mm. This provides a unique opportunity. to process large surfaces as quickly and efficiently as possible.

Skorpio E is considered to be a very complete grinding device, which does not require additional installation of a compressor for its operation. Its functionality is sufficient for efficient processing of deep damage in any area.

iBrid

The model on the Russian market is found in several variations:

  • rotary;
  • rotary-orbital.

Main technical parameters:

  • eccentric stroke indicators. 3 or 9 mm;
  • circle with a diameter of 40 or 70 mm. Depending on the selected tool model;
  • rotation speed varies from 2 to 5 thousand revolutions per minute;
  • power is supplied from a 220 V power supply or a rechargeable battery.

The main advantages are compactness, the ability to work in an autonomous mode (on a single charge). A distinctive feature is to carry out work in hard-to-reach places.

Not recommended for use on a plane. When working with deep damage, the model has proven itself not from the best side.

LHR12 (Duetto)

The model is equipped with the most balanced circle with a diameter of 150 mm. It can be used as a tool for processing large areas, for example, an automobile hood and mid-planes:

  • doors;
  • trunk, etc.

The eccentric has a stroke of 12 mm, which makes it possible to use the tool as a grinder. Additional features include a modern compact high-quality case, which at first glance may seem unusual for craftsmen with extensive experience.

Note: LHR15 is one of the replacement options with a classic body, but without the ability to carry out grinding work.

What are the machines?

Depending on the functions performed and design features, the sighting device can be:

  • Collapsible. One of these products is the Benchmaster Shooting Tab. The set consists of a table and a chair, which, if necessary, can be easily disassembled. This machine allows the rifle to be zeroed in a sitting position.
  • Stationary.
  • Universal.
  • Specialized, i.e. designed for certain types of weapons. Mostly on such devices, air rifles are zeroed in. A feature of such machines is their low weight.
  • Designed for sighting only.
  • Used in the service of guns.

Stages of work

  • Cut the metal pipe so that you get two pieces 700 and 400 mm long.
  • Grind burrs in the pipe sections obtained.
  • In order to prevent deformation, you need to insert wooden beams into the ends of two pieces of pipe.
  • Cut the hairpin into two pieces 400 mm long and chamfer them.
  • Two holes must be drilled in the pipe section (700 mm). Their indent from the edge of the metal piece should be 20 mm.
  • Drill four holes in the section (400 mm). Two of them should be located 20 mm from the edges of the pipe (as is the case with a large piece), and the two holes between them should be placed 150 mm apart.
  • Using a bolt, join the long and short sections at the corners. It is recommended to place washers between them in order to prevent paint abrasion. Its presence will preserve the color coating of the machine in cases when it is folded. A wing nut is used to fasten the bolt.
  • On a short section of the pipe, you need to install the studs and fasten them firmly with nuts. When making a machine for zeroing a carbine with your own hands, it is very important to pay attention to the reliability of the connections, since the presence of a backlash can adversely affect the accuracy of fire.
  • Insert a washer in a short metal section in the outer hole, and then a bolt and a wing nut. The presence of a limiting nut will enable the owner of the machine to carry out its adjustment in the horizontal plane.
  • Fix the carabiner stop with a 150 mm long bolt. This work is done on a long stretch. The bolt is installed in the second hole.

How to make a machine for zeroing a carbine with your own hands?

Before operating any small arms, it is necessary to determine its characteristics. You can cope with this using the zeroing procedure. By doing it manually, it is impossible to get accurate results. Therefore, today, professional military personnel, hunters and amateurs of guns and pistols widely use a special machine for sighting weapons. This device is now also used to train personnel of the armed forces of many countries of the world.

About drawings

For a craftsman, if he has the necessary materials and tools, it will not be difficult to make a machine for shooting a carbine with his own hands. Drawings of such devices are of interest to many who want to facilitate the process of creating a sighting structure. During the manufacture of the machine, the master can perform complex turning, milling and welding works. The process can be greatly simplified by creating a do-it-yourself rifle zeroing machine from a metal pipe. Construction drawings by craftsmen are mainly replaced by generous publications of photos of the finished device, recommendations for its manufacture and description of the technology. Or they are offered for purchase on the Internet subject to a significant prepayment. Therefore, they are a kind of deficit, very much in demand in the networks.

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What is the essence of sighting?

The objective of this event is to combine the point of average hits of the weapon with the target’s sight. It can also be the crosshairs of optical sights.

In the course of work, the following is carried out:

  • sighting in the sight;
  • the accuracy of hits is determined;
  • selection of a certain type of bullets.

It is desirable to carry out zeroing in the shooting range. closed space, in which the influence of wind is excluded. The essence of the work is to securely fix the small arms in the machine and then fire at a certain distance to the target. The carbine located on the frame is guided to the target by special regulating elements. The weapon fixed in the machine acts as a heavy machine gun.

The end result of good zeroing is that the shooter finds the midpoint after a few shots. After that, by tightening the flywheels, the aiming mark is aligned with the hole formed after the shot in the target.

What is a sighting machine?

The product is a special device that allows rotation when aiming a fixed small arms. Many firms specializing in the manufacture of weapons also sell these systems.

Despite the variety of models, any zeroing machine performs one function: with the help of a rigid base it reliably secures the weapon, eliminating any impact on it of human and weather factors.

What tool to work?

You can make a machine for zeroing a carbine with your own hands using the following inventory:

  • angle grinder (angle grinder);
  • electric or hand drill;
  • screwdriwer set.

Safety engineering

Never neglect the safety precautions when working with the grinder. At the end, I will tell you a real case from my practice. But in order.

Disk balancing.

Expensive grinders are able to automatically balance the disc. When cutting, very often the disc wears out unevenly. To avoid strong vibrations during operation, the spindle has a clever bearing that balances the uneven disc.

Soft start system.

Many powerful grinders of the more expensive segment are equipped with an electronic system that smoothly starts the disc. Those. the disc does not turn on instantly, but with current limitation and, with an increase in revolutions, the current increases to a maximum. Although this happens quickly and in order to determine whether there is such a system in an angle grinder, you will need to turn it on. If the angle grinder does not jump out of hand when turned on, the system works.
However, do not confuse a soft starter with a weak angle grinder. There are angle grinders themselves low-power. They start up with a slight jerk and spin up for a few seconds. But it is worth touching such an angle grinder to the working material, as the speed drops significantly.

Disks.

Always make sure that the disc is inserted correctly. Cutting discs are thin. Thick. for grinding. Do not tempt fate and try to gently grind surfaces with a cutting disc.

I do not recommend placing circular discs on an angle grinder. For cutting wood, there are other machines.

If you do not neglect these simple safety rules and use high-quality discs, then they will not break and fly in all directions. I did not insert photos from the Internet, which happens when the safety requirements are not observed when working with an angle grinder. Look for yourself.

By the way, in addition to the grinders we are used to, there are battery-powered machines, which is sometimes very useful.

Almost every brand that produces power tools has such machines.
Enjoyable and safe work for you!

p.s. And finally,

Handle attachment options.

There are machines with a fixed main handle and an additional handle that can be unscrewed. And there are grinders where this very handle can be screwed in from the other side or from above.

What you need to know about angle grinder

The angle grinder, or, as we often call it, the angle grinder, came to us, oddly enough, from an angle grinder in the 1970s.

In general, an angle grinder (or grinders) is a rather broad concept. But I will tell you about the features of working with an angle grinder from the point of view of a plumber. I will share examples from my experience. And I will say a few words about safety when working with the tool.

For myself, I have divided the angle grinder into three types: small, medium and large. (We do not take into account very large ones)

The best combination, in my opinion, is to have a large and small angle grinder in operation.

The small angle grinder is very comfortable to crawl into tight spaces, it is lighter and safer (easier to hold)
a medium-sized angle grinder. this is the very alternative when there is no big, and you can not finish with a small one.
Well, the large one is designed for cutting large pipes (it has a large cutting depth). Those. has a disc of a larger diameter and, accordingly, a cut is obtained deeper, which is important when working with large diameters.

Once or twice for household needs or every day (professional need)?
If you need an angle grinder for a one-time job or you buy one just in case, then buy a household one. It is inexpensive, and if you have to work all day, just let it cool down every half hour.

If for household needs you want a more reliable angle grinder (so as not to overheat), then I recommend taking a small angle grinder at a price of 3-4 cheap ones. Large cutting machines for household purposes are rarely needed. When working with pipes, the small angle grinder can cut pipes up to a diameter of 50 mm (with a 125 mm disc)
When buying an inexpensive angle grinder, it must be borne in mind that it will not be able to serve for a long time, because it is made of cheaper materials.
The first thing that usually “flies” at a household angle grinder during intensive use is the gearbox bearings.

Dust protection

When working on an angle grinder for long periods of time, be sure to use a respirator. You can ordinary

Or use a half mask with a charcoal filter

Protection against accidental activation.

Most of the angle grinder are equipped with a safe power button. To launch such a tool, you need to push the lever forward and only then press the button.

Soft start: yes or no

The angle grinder is a pretty powerful tool. If we take into account the models with a power of 2. 2.5 kW, then they can be compared with a washing machine. When the instrument is connected to the mains, critical loads occur. Such loads can damage the network. This can be prevented by using a soft start, which is widely used on modern angle grinders.

The presence of such a function can be determined by the operation of the tool. If the angle grinder starts up smoothly, without any jerk, then the soft start is installed in it. This allows not only to create comfortable working conditions with tools, but also to protect its structural elements from rapid wear.

How to make POLISHER MACHINE from ELECTRIC DRILL and old ANGLE GRINDER

Working circle diameter

Also here it is necessary to remember about the features of certain models. So, for example, if we are talking about household angle grinders, then they have a one-sided handle fixation. As a result, such tools are only able to work with circles up to 12.5 cm in diameter. If the model is equipped with a double-sided fixing of the handles, then it is possible to install discs from 18 to 23 cm on it.Of course, in some models an additional removable handle is provided, which makes it versatile for various jobs.

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If we talk about popularity, then the first place is taken by an angle grinder with a circle diameter of 12.5 cm.It is such models that are in great demand and are widely used both in everyday life and in construction.

Ergonomic angle grinder

When choosing an angle grinder, you should pay attention to its weight and ease of use. Specialists recommend paying special attention to the holder. The handle will control the machine during operation. Therefore, its location should be convenient. Among other things, the holder absorbs some of the vibrations that occur during the operation of the angle grinder. Therefore, it must have anti-vibration function.

As for the weight of the tool, this parameter largely depends on its power. So, for example, if you take an angle grinder with a power of 0.8 kW, then it will weigh on average 2 kg. Higher wattage models will weigh more. For example: a 5 kW machine weighs about 3.5 kg.

It is also worth knowing that there is a wide selection of angle grinders on the market today. Previously, models were produced that work exclusively on a household network. But, modern tools are capable of operating from rechargeable batteries. Of course, such models are quite expensive compared to conventional angle grinders. But, they have a number of advantages that make this price difference completely insignificant.

The main advantage of cordless tools is their ease of use. Now the operator’s movements are not limited by the length of the network cable. This angle grinder can be used in places where it is not possible to connect to the electrical network.

Of course, you need to understand that batteries have limitations in their work. Therefore, periodically they will need to be put on charge. If the tool will be used for a long time, then it is worth paying attention to models with a high battery capacity. You can also extend the operating time using a replaceable battery. So, while one is charging, the other can be installed in an angle grinder and work with it.

What you should pay attention to. Electric power

Probably, an important indicator of such a tool is electrical power. Today on the market you can find an angle grinder, the power of which ranges from 05 kW to 2.7 kW. When choosing, it is worth considering the fact for what purpose the tool will be used. If the angle grinder will be used exclusively in everyday life, then a model with a power of up to 1 kW will suffice. With the help of such a tool, it will be possible to easily cut and grind some material in a short time.

If the angle grinder will be used often for construction purposes, for example, for cutting concrete, then it is worth choosing models with a higher power. A tool with a power of 1.5. 1.7 kW will be the optimal solution for such cases.

Features of the instrument and a bit of history

Looking deeper, the angle grinder is an angle grinder. The name of the tool is due to the fact that its assembly was carried out in an angle grinder. It was this country that was the supplier of such construction tools. In the Soviet Union, the angle grinder appeared in the 70s. last century. In the West, this tool has already been widely used for various purposes. Such a lag in development was explained by the fact that the USSR then did not focus on the construction industry.

The first models of this tool were used exclusively for grinding certain surfaces. This is already over time, the angle grinder began to be used for cutting hard materials. Today it is difficult to imagine construction without the use of such an irreplaceable tool. Indeed, it can be used to cut metal, ceramic tiles and other materials that are used for the construction and decoration of buildings.

If you analyze the modern market, it can be noted that the angle grinder is divided into two main types:

In addition, the angle grinder is also distinguished by the size of the working wheel. The most common options are models that work with a canvas with a diameter of 12.5 and 25 cm. Of course, there are other discs with a diameter of 18 and 28 cm.

It should be borne in mind here that the diameter of the working blade largely depends on the power of the motor. So, for example, if you put a wheel that is slightly smaller than necessary on an angle grinder, this can lead to its destruction. In addition, what materials the angle grinder can work with depends on the power of the motor. If the tool is chosen for cutting steel, then it is best to opt for 2kW models.

The tool consists of such basic elements as:

  • Housing. This is the main part of the angle grinder that houses the power unit.
  • Rotating spindle. The necessary attachments are attached to it.
  • Toothed front that connects the spindle to the motor.

As you can see, the angle grinder is not as simple a tool as it seemed at first glance. Therefore, her choice must be approached very carefully.

Electric angle grinder or how to choose a grinder

An angle grinder is an electric tool that is designed for cutting, cleaning and grinding various hard materials. Such materials include concrete, metal, stone and others. Of course, today they are developing circles, the main working element of the angle grinder, which will work with other materials with lower hardness. So, this will allow you to use the tool for cutting wood and other materials. Today we will try to figure out what an electric angle grinder is and how to choose a grinder.

Before deciding this issue, I propose to consider what the tool is and its based characteristics.

Spindle travel speed

Discs with a diameter of 11.5 cm can rotate up to 11 thousand times per minute. If a canvas with a diameter of 20-30 cm is used in the work, then it is better to opt for models that are capable of accelerating it to 6.6 thousand revolutions. If you neglect this rule, then during the operation of the angle grinder, destruction of the working blade may occur. And this, as you know, is very dangerous for the life and health of others. Of course, some models are equipped with switches that allow you to adjust the torque of the tool.

Tool safety

An important requirement for such tools is safety in use. This is especially true for machines that have a lot of power. The main protective element is the casing. It protects the operator from dust, sparks and small particles that form during the operation of the angle grinder. Experts do not recommend using a tool with a removed or damaged cover, as this may cause injury.

It is also worth remembering about the means of protection. Work with an angle grinder should be carried out in special glasses and gloves, which will protect the skin and organs of vision from damage.

So, it is worth recalling the basic safety rules while working with tools:

  • Before starting work, it is necessary to check the integrity of the casing and the mains cable. It is undesirable to use a tool that has significant damage and defects. Doing so can cause destruction of parts and injury to the operator.
  • Work must be carried out in protective goggles that have a sufficient degree of protection.
  • Hold the angle grinder as tightly as possible during operation. For example, if the disc suddenly jams, the angle grinder can be knocked out of your hands. As a result, this will not only damage the instrument, but also cause injury.
  • Material that can be cut or grinded must be well anchored.
  • Do not put pressure on the angle grinder during operation to speed up the process. It can break the circle.
  • the angle grinder is not used for cutting wood.
  • Now you know not only how to choose a tool, but also how to use it correctly to protect yourself from injury.