Corner grinder is you need speed adjustment. What is a revolution regulator and why it is needed

Do.it.yourself

An integrated option for adjusting the number of revolutions of the circle will make it possible to carefully process materials such as wood or plastic. At low speeds, comfort and safety increase. The most practical option is in the radio and electrical work, one hundred and studios involved in restoration.

In addition, among professionals using the power tool, there is a judgment that the more trivial the device is arranged, the more reliable it is. And it is advisable to remove the additional service “filling” by the boundaries of the corner grinder. With a similar approach, equipment maintenance is greatly simplified. In this regard, some firms deliberately produce outdoor individual electric controllers connecting to the network cable angular grinder.

This is interesting: how to work properly with a corner grinder. cut, saw, hold, put a disk

Chips on the choice

How to choose the right corner grinder? To do this, use several basic criteria.

To select a suitable tool, you should decide on a specific type of work that is to be performed by this tool. Corner grinder can be of different types: network, with batteries, gasoline and pneumatic.

Network models are perhaps widespread most. Such corner grinders work from a home network, that is, from a simple outlet. Such tool models have high power, compactness and high rotation speed of cutting discs.

Battery devices are deprived of this minus. They have a special mount for power supply, which are charged from the mains. After charging, you can work with such a tool without any wires. Typically, such corner grinders have compact dimensions and small diameters of cutting discs. As a rule, such models are more expensive than standard tools. Also, the period of their work is limited by the capacity of the power supply.

Bulgarian gasoline models are infrequent. Such devices are characterized by large dimensions, because they need a fuel tank, as well as an internal combustion engine. Among the advantages, it is worth highlighting the high power of these models, a wide range of disks selection and autonomy. Negative aspects include their weight and volume, high noise level and, of course, additional fuel costs for the device.

Pneumatic models angular grinder are often used for production purposes and very rarely for household work. These are unusual corner grinders that work from the stream of compressed air, need a special compressor. In such models, the problem of overheating is completely excluded, and the period of work can be limited only by the human factor. Also, such models are the lightest and most silent.

For simple work on processing and grinding surfaces, light models of grinding machines with a small diameter of the cutting circle are suitable. For the cutting of strong materials, it is worth selecting a more powerful and, accordingly, bulky equipment with a large diameter of the disks. Diameters of the discs can be from 125 (minimum size) to 230 (maximum size) mm. that is, the size range is quite wide. The universal diameter of the cutting disk is 180 mm. In such a circle you can process surfaces and cut the material.

When choosing a disk, you should conduct an attentive visual inspection. Even small injuries and chips can lead to extremely sad consequences. By the way, almost 90% of accidents when working with an angular grinder occurs due to the fault of the defect on the cutting discs.

An important criterion for choosing is the convenience of work. The corner grinder should be equipped with comfortable handles, should not slip out of the palm of your hand and have a large weight. Many corner grinders have an electronic relay to protect against voltage and overload jumps. This is a useful function, so you should choose a tool with such a fuse.

Do.it.yourself manufacture

For manufacture, many try to install a dimmer from lighting lamps or a rotation regulator of a vacuum cleaner. Nothing will come out of this due to high loads in the first case and the difference in the number of revolutions in the second.

To independently make a device to adjust the speed of rotation, you need to be able to read and develop electronic circuits and embody them into a finished product. Otherwise you just need to buy a ready.made regulator or corner grinder with it.

For the manufacture of an elementary thyristor design regulator, you need to purchase five necessary parts on the radio market, and the device itself will fit in the case without problems. But the corner grinder with such a device will lose speed when using. It will only be enough for polishing and working with soft materials.

If serious work with large diameters discs is planned, the regulator on the KR1182PM1 chip, or a similar imported. This scheme will provide a minimum power drop and maintaining revolutions, and also does not wear out the electric motor.

Especially important is the issue of adjusting the revolutions in the manufacture based on an angular grinder of various stationary machines like a circular saw. Then the regulator can be connected in a separate starting machine.

Any method of correcting the rotation of the device expands the spectrum of its application and work with it becomes more convenient and safe.

Tips for choosing a corner grinder with a smooth start

To work far from energy sources, choose a tool working from the battery. This increases the cost and limits the operating time, but allows you to use corner grinding even in the field.

There are also gasoline and pneumatic corner grinders, which are used mainly at industrial enterprises. Devices with internal combustion engines do a great job with a sharp overall blanks with a diameter of up to 400 mm. Models working from compressed air need a compressor with a capacity of 200-400 l/min.

Consider the other parameters affecting the choice of corner grinder.

The size of the disks used

All discs for the Bulgarians, including devices with the function of speed adjustment, are divided into two types: cuts and references. The diameter of the circles varies from 100 to 500 mm. The most common sizes are:

On the overall models, it is allowed to install a smaller diameter, provided that the landing hole is complied with.

It should be remembered: the larger the size of the disk, the more massive the device will be. This will affect the duration of the working cycle.

Engine power

The power of household models does not exceed 1 kW. For professional devices, this parameter can reach 5 kW.

The depth of cutting directly depends on the size of this parameter.

The presence of manual and electronic protection

Busting the disk during operation is the biggest nuisance. Corner grinder can break out of the hands and cause serious damage. Possible reasons:

• Circle contact with an outsider;
• work with too durable item;
• Weak tightening of the spindle nut;
• exceeding the maximum number of revolutions;
• Disk operation, the material of which does not correspond to the processed surface.

All this leads to the fact that the working nozzle breaks or spreads into parts. In the latter case, fragments flying at high speed are a danger to human health.

To reduce the risk of injuries, manufacturers equip the tool with mechanisms of protection against jamming.

All inexpensive models have a special casing to protect against disk fragments in case of jamming. These are international safety requirements.

Protection systems can be divided into two types:

• Mechanical. Special couplings are installed on professional models with the function of speed adjustment. In the case of overloading or jamming the disk during the transmission of torque, it begins to slip, preventing damage to the nozzle.
• Electronic. In this case, a special security unit is responsible for an emergency stop. Its principle of operation is based on reading electrical parameters during operation. A sharp termination of rotation is accompanied by a leap of current, which sensors instantly react to, de.energizing the tool.

Other functions

• Protection against random inclusion. Two launch buttons are installed on the corner grinder. Inclusion occurs only with the simultaneous press.
• Work stabilizer under load. When cutting especially dense materials, the electronic system automatically supports a given number of revolutions. The function is useful to masters who work with overall blanks of stone, marble or concrete.

How to make a regulator from a dimmer?

A very effective and easy solution to this issue will be the creation of a remote frequency converter. In the role of a converter, you can use a dimmer. a device for regulating the level of illumination. When creating, you will need an electric carrier and a fork. I must say that the implementation of such a device can be performed by different methods. Especially simple are 2: using an automatic machine and without it.

• Screw 2 wires to the ends of the electro.outlet so that one is more authentic. After that, connect the long end to one of the contacts on the fork. The end of the 2nd wire is fixed on the contacts of Dimmer, and its other conclusion is connected to the 2nd contact of the fork.
• When using the 2nd version, it is necessary to make a number of modifications to the circuit, and specifically place the gun on the cord between the fork and the dimmer of the machine. Mostly ordinary switches are provided in dimmers, but we need automatic, which, if something goes wrong, will turn off our device from the mains.

So, the frequency converter of the angle grinding machine is ready, and for practicality it can be placed in a specialized case or fixed on the wood panel. It should only be taken into account that such a device is homemade, and when working with a power grid, you must be careful.

About how to make a speed controller for a corner grinder with your own hands, watch in the video below.

How to disassemble an angular grinder for diagnosis

To diagnose the electrical part of the corner grinder, as well as eliminate the mechanical breakdowns of the device, you will need to disassemble it. Dismantling is carried out according to the following algorithm.

After extracting the anchor, the engine stator will remain in the casing, which is also easily extracted for diagnosis after unscrewing the fasteners.

Installation of a regulator on an angular grinder

Do.it.yourself revolutions control regulator can be mounted in four versions:

Installation of a regulator on an angular grinder. diagram

• in the handle;
• into the outer box, which is attached in a convenient place on the tool body;
• into the cooling cavity (manufacturers use this particular option);
• On the network cable.

Installation of an additional box does not require cutting the case for the output of the regulator, but the place should be chosen very meticulously so that the innovation does not interfere with convenient to keep the tool. Installation in the handle or cooling cavity will need to cut a hole for the output wheel, the main thing here is not to lose the rigidity of the protective casing and clean the edges well so that you do not hurt your hands when working.

Often the best option is the wire mount. In this case, the regulator is easy to test, you do not need to think about the place and method of fastening (island and the plastic case are quite suitable). If desired, it can always be removed and remade.

Advantages of universal corner grind

Corner grinder (angular grinder) Metabo Wev 10-125 Quick 600388000 (in the box). Photo 220 volts

It is not always a regular corner grinder without additional options that it is possible to solve the problem of processing some types of materials, the working tool is not adapted for efficient revolutions that the angular grinder gives out without a speed regulator. Especially acute the problem of choosing the necessary modes faces users engaged in grinding, stripping, polishing various materials. To perform work, sometimes you have to look for another tool with suitable characteristics.

Universality angular grinder with adjustment of the number of revolutions just consists in the ability to set the speed of rotation, for example, cord.shaped when cleaning. When performing grinding operations, the contact spot between the working tool and the processed surface increases, which requires the use of high.power grinder. Such corner grinder with additional options installed on them perform almost any type of work with various materials.

Criteria for choosing a corner grinder with an electronic rotation frequency regulator

Corner grinder with an electronic revolution regulator is far from a cheap purchase option. The volume of work should be clearly represented, the performance of which will need a change in the speed of rotation of the working tool. Having made sure the validity of the purchase of a corner grinder with such an option, the technical characteristics of the corner grinder are selected in combination with the capabilities of the electronic control unit to influence the selection of the operating mode. Detailed information about the selection criteria can be found at the link “Choose a corner grinding grinder with speed control”.

What is this function, principle of operation, electrical circuit, pluses angular grinder with a regulator

Most of the models of the Bulgarians do not have a built.in revolutionary control regulator, as on vacuum cleaners. Such devices work only at maximum rotation speed. However, if you integrate a special regulator into them, a person will be able to lower the momentum to such a level that one or another material can be better processed.

For what purpose is the angular grinder low speed

Many people are interested in why it is necessary to adjust the speed on the corner grinder. Most often people decide to reduce the speed of rotation of the circle in order to more carefully process plastic or wood.

Also, at reduced speed, the safety of using such a power tool increases. The fact is that at low speeds, the corner grinder vibrates less and sits in the hand much better.

Additional Information! Many professionals who regularly use Dewalt or Interskol grinders at home, recommend that the speed regulators outside the device be removed. This simplifies the tool maintenance. In addition, the corner grinder will not have to be disassembled if the rotation settings module breaks.

Why corner grinding is a smooth start and a revolutionary control regulator

In modern models of angle grinders, two technologies are used that increase the safety and characteristics of the power tool:

• Rotation speed regulator. This device is installed so that a person can switch the mode of operation of the motor.
• Smooth start. Most often this function is found in expensive models from dimmer. When using smooth descent, the work of the motor will gradually increase from the zero mark to the maximum value.

The above technologies are very useful. The fact is that with their help it is possible to reduce the wear of the tool and increase its life. Therefore, people who have decided to purchase a corner grinder are recommended to look for models with built.in smooth descent and a rotation regulator.

Connection diagram without power regulator

People who have decided to independently connect the device to set up revolutions should familiarize themselves with the corner grinder circuit in advance. This will help to understand how everything works in it.

The main element of the entire scheme is the stator. He has two on interconnected windings. They are connected to a voltage source through a separate switch. It is in it that the start button is installed, which is responsible for the start of the operation of the corner grind.

Each of the existing windings is connected to graphite brushes using special contacts, which are securely connected to the surface of the collector. At the same time, the ends of the winding are connected to collector lamella. As a result of this, a closed electric circuit is obtained.

How to make adjustment for angular grinder at home, home.made options

If a person wants to get a free adjustment for a corner grinder, you can try to make it yourself. However, before this it is necessary to familiarize yourself with how to make it correctly.

Without loss of power

Many people dream of creating a home.made device for regulating revolutions without further power loss. However, in fact, it is almost impossible to make them. The fact is that such regulators should be equipped with special sensors. They independently monitor how quickly the circle rotates and, if necessary, adjust the speed. Only manufacturers of Bulgarians can do such devices.

Important! At home, it will be possible to make regulators on semiconductor schemes. They do not guarantee complete conservation of power when changing the speed of revolutions.

Electronic device testing

People who managed to independently assemble the regulator should test it before connecting to a corner grinder. This must be done to verify the performance of the manufactured module.

To check the serviceability of the regulator at home, you will need an overhead electric socket. Two wiring is installed in it, one of which is connected to the board. The second must be connected to the network cable.

When all the wires are connected, you get a sequential electric circuit. To check the regulator to the circuit, you need to connect the light bulb and try to reduce its power. If its brightness began to decrease, then the electronic device works and it can be put in a corner grinder.

How to reduce/increase the speed of disk rotation

There are situations when it is necessary not only to reduce, but also to increase the speed of rotation. In this case, it is not necessary to understand how to make a corner grinder with a do.it.yourself speed adjustment. It is much easier to buy a universal Chinese regulator, with which it will be possible to change rotation speeds.

Such devices are sold in separate plastic boxes. They are equipped with an outlet for connecting a corner grinder and a cord with a fork for connecting a device to a power source.

Additional Information! It is quite convenient to use such modules. You just need to connect a corner grinder through the installation and select the operating mode on the regulator.

How to put, connect

A device to reduce and increase speeds can be connected in various ways. There are two methods that are most often used when connecting the regulator:

• As an external control device. It is recommended to place such modules outside the power tool. Quite often, people install boards on semiconductors to regulate the power of corner grinders into network carrying.
• Installation inside the tool. This method is extremely rare. The fact is that mounting the device into the case is quite problematic due to a small amount of free space. Also, this method is not popular due to the fact that the regulator will often overheat in the corner grinder body.

Additional Information! If you can’t connect the regulator yourself, it is necessary to entrust this work to a professional.

How to disable, remove voltage sensor

There are situations when you need to get rid of the connected module to set up revolutions. Most often this happens if the device fails and because of this it is not possible to use the corner grinder. In this case, only one thing remains. to disconnect the sensor.

Disable the regulator is quite simple. If it is mounted in the tool, you will have to remove the case and carefully disconnect all the wires. When using the external module, it is still easier. It is necessary to disconnect it from the outlet and corner grinder.

Electric equipment device for corner grinders

For 40 years, the appearance of the corner grinder has practically not changed: an oblong body with an engine mounted inside and a gearbox, a screwed handle and a protective casing on the side.

Corner grinder, like any tool, sooner or later refuses to work. But there are situations when the simplest repair of electrical equipment is sufficient to eliminate the malfunction. To carry out this minor repairs, you need to have a concept of how such equipment works inside, and be able to read its electrical circuit.

The electrical circuit of a grinding machine consists of such elements:

How to disassemble an angular grinder for diagnosis

To diagnose the electrical part of the corner grinder, as well as eliminate the mechanical breakdowns of the device, you will need to disassemble it. Dismantling is carried out according to the following algorithm.

Using the key, remove the disk or other nozzle from the unit spindle.

After extracting the anchor, the engine stator will remain in the casing, which is also easily extracted for diagnosis after unscrewing the fasteners.

Connection of a smooth start

The electronic speed controller is mainly needed by domestic masters to expand the capabilities of corner grinder in terms of grinding and processing soft materials. Professionals, as a rule, use a specialized tool for certain types of work and use an angular grinder only for its intended purpose. With a smooth start device, the situation is different. For a household purpose tool that has a slight power, this option is useful, but optional. But for professional Bulgarians with drives over 1000 watts, it is vital. In addition to the above improvements of operational characteristics, smooth start is extremely important for the safety of the operator. Corner grinder with a circle of Ø230 and a capacity of 2000 W weighs 5 ÷ 6 kg, and in order to keep it during a starting jerk, certain efforts and a stable position are required.

The smooth starting unit can be purchased in retail chains and self.control over the case any corner grinder inside the case. The video below shows its installation on a new powerful corner grinder acquired by the author for food. This video is also interesting in that its author, using a switch device, demonstrates the value of the current jump when the corner grinder is turned on first without smooth start, and then with this device.

The most advanced control device for corner grinding is the system for maintaining revolutions under load, which also performs the functions of the rotation speed regulator and provides a smooth start. On the Internet you can find a scheme for manufacturing such a device on the U2010b chip, but it is quite complicated even for those who have the initial skills of amateur radio. Is it possible to purchase a ready.made unit maintaining speed and how much it costs? If someone can answer this question, please share information in the Комментарии и мнения владельцев.

Features of the installation of the finished block

In the purchase and installation of an industrial regulator, the corner grinding grinder is inwardly, in most cases it is necessary to modify the body. cut a hole in it to output the adjusting wheel. However, this can adversely affect the stiffness of the casing. Therefore, the installation of the device outside is preferable.

The numbers on the adjusting wheel indicate the number of spindle revolutions. The value is not absolute, but conditional. “1”. small turnover, “9”. the greatest. Other numbers are used to orientation when regulating. Placement of the wheel on the case can be different. For example, on the angular grinder of Bosch PWS 1300–125 CE, Wortex AG 1213–1 E or WATT WWS-900, it is placed at the base of the handle. In other models such as Makita 9565 CVL, the adjusting wheel is located in the end of the casing.

The regulator connection diagram to the corner grinder is not not easy, but from time to time it is not always easy to stretch the cables to the button, which is placed on the other end of the device case. The task can be dared to select the rational cross.section of the wire or its withdrawal to the surface of the casing.

A good option. installing the controller on the device for another mount to the network cable. It rarely comes out of the first sample, you have to test during the device, then make some adjustments. This is easier to do when access to its elements is open.

Fundamentally! If there is no experience with electrical circuits, it is more advisable to purchase a ready.made factory regulator in other words of an angular grinder equipped with this function.

Why you need to adjust the speed to the corner grinder

Any corner grinder is constructively “sharpened” to work only with a cutting or a circle of a certain diameter. There are six of the most common diameters in the interval of 115 to 300 mm, which corresponds to six groups of spindle rotations at idle. For example, a corner grinder with Ø125 mm circles have a rotation frequency of about 11 ÷ 12 thousand. rpm, and with circles Ø150 mm. 9 ÷ 10 thousand. rpm. Such values ​​of the spindle revolutions are due to the fact that the cut.out discs are designed for high.performance hardening of solid materials (metal, stone, ceramics) at cutting speeds up to 80 m/s.

However, when cutting and especially grinding soft and viscous materials, completely different cutting parameters are required and, accordingly, the use of a tool with a speed regulator. over, this applies not only to wood and plastics, but also to steels, alloys of titanium and aluminum. For example, the processing of plastic and soft varieties of wood occurs at cutting speeds from 8 to 12 m/s, grinding of titanium and stainless steel alloys. within 15 ÷ 20 m/s, and even ordinary steel is grinded no more than 30 m/s. Therefore, the speed of rotation of grinding nozzles in the Bulgarians should be less than the passport several times. At the same time, it should be noted that in the bulk of the revolution regulators, the angular grinder is inherently the power regulators supplied to the electric motor of the corner grinder. That is, a decrease in the number of revolutions is achieved by a decrease in the power of the source by a value of up to 15 % of the nominal. But for grinding and cutting soft materials, this does not matter much, t. to. In this case, a small power is initially required.

Revolutions and smooth start. for what we need

In modern grinders, two important functions are used that increase the reliability and safety of the tool:

• revolutions control. a device designed to change the number of engine speeds in various operating modes;
• Smooth start. a scheme that provides a slow increase in engine speed from zero to maximum when the device is turned on.

They are used in electromechanical tools, the design of which uses a collector engine. Help to reduce wear of the mechanical part of the unit during inclusion. Reduce the load on the electrical elements of the mechanism, putting them into the work gradually.

When the power is turned on, a spasmodic transition occurs from rest to rotation of the disk at a speed of 2.5–10 thousand revolutions per minute. Those who worked with a corner grinder are well known that the machine simply “breaks out of the hands”. It is at this moment that the overwhelming amount of breakdowns associated with the mechanical part of the unit occurs.

The windings of the stator and rotor are experiencing no less load. The collector engine starts in a short circuit mode, the electric motor is already pushing the shaft forward, but inertia still does not allow it to rotate. There is a leap of starting current in the coils of the electric motor. And although they are structurally designed for such work, sooner or later the moment comes (for example, when jumping on the network), when the insulation of the winding does not withstand and there is an interval closing.

When the tool starting circuit and changes in the engine speed is included in the electrical circuit, all of the above problems automatically disappear. Among other things, the problem of “failure” of voltage in the common network is solved at the time of launching a hand tool. And this means that the refrigerator, TV or computer will not be dangers of “burning out”. And safety machines on the counter will not work and turn off the current in the house or apartment.

The final starting scheme is used in the grinders of the middle and high price categories, the revolutionary control unit is mainly in professional models angular grinder.

Additional electric circuits increase the cost of the tool, but increase the service life and level of safety during operation.

Why do you need a smooth start

The presence of such a start is a very important point. When the powerful power tool connected to the network is launched, the starting current is thrown, which is many times higher than the rated current of the engine, the voltage in the network sags. Although this throw is short.term, it causes increased wear of the brushes, the engine collector and all the elements of the tool according to which it proceeds. This can cause the failure of the tool itself, especially Chinese, with unreliable windings, which can burn at the most inopportune moment during the inclusion. And there is also a large mechanical jerk when starting, which leads to rapid wear of the gearbox. Such a start extends the life of the power tool and increases the level of comfort during operation.

The electronic unit allows you to combine the speed control and smooth start into one whole. The electronic circuit is implemented according to the principle of impulse. phase control with a gradual increase in the phase of the opening of the systemist. Such a block can be supplied with corner grinders of different capacities and price category.

Varieties of devices with an electronic unit: examples in the table

Angle.grinding machines with an electronic unit: Popular in the photo

FELISATTI AG125/1000S Bosch GWS 850 CE Makita SA5040C Makita PC5001C FLEX LST 803 VR

Do.it.yourself revolutions

The revolution regulator is not installed in all models of the Bulgarians. You can make a block for adjusting revolutions with your own hands or purchase a ready.made.

Factory regulators of the revolutions of the Bulgarians: photo examples

BOSH Bulgarian revolution regulator control controller Bulgarian BOSH RIGNITAL RIGHTARM STURM RIGNITAL RIGHTARM DWT RIGNITAL RIGHTARTION DWT RIGHTS

Such regulators have a simple electronic circuit. Therefore, creating an analogue with your own hands will not be difficult. Consider what the speed control for Bulgarians is assembled from up to 3 kW.

Production of printed circuit board

Since the circuit is very simple, there is no point in installing one to install a computer program for processing electric circuits. Especially since printing needs special paper. And not everyone has a laser printer. Therefore, let’s go the easiest way to make a printed circuit board.

Take a piece of textolite. Cut the necessary size for the chip. Roll the surface and degrease. Take a laser disc marker and draw a scheme on a textolite. In order not to make a mistake, first draw with a pencil. Next, proceed to etching. You can buy chlorine iron, but after it the sink is poorly washed. If you accidentally drop the clothes, there will remain spots that cannot be removed to the end. Therefore, we will use a safe and cheap method. Prepare a plastic container for the solution. Pour in hydrogen peroxide 100 ml. Add the floor of a tablespoon of salt and a bag of citric acid up to 50 g. The solution is made without water. With proportions, you can experiment. And always make a fresh solution. Copper should be scattered. It takes about an hour. Wash the board under a stream of deck water. Drill holes.

You can make it even easier. Draw a scheme on paper. Glue it with tape to the cut textolite and drill holes. And only after that to draw a scheme with a marker on the board and poison it.

Wipe the alcohol board with a rosin flus or a conventional solution of rosin in isopropyl alcohol. Take a little solder and tire the tracks.