Choice Of Angle Grinder 125 Mm With Speed Controller

15 best grinders (angle grinder)
Top popular angle grinder. According to the reviews of professionals and amateur craftsmen.

Criteria for Selecting a Good Angle Grinder

Number of handles

The convenience and safety of work depends on this parameter. The angle grinder comes in one-handed and two-handed. The first option is common among relatively light models, both household and professional. The lightweight angle grinder can be simply supported with the other hand on the body. The two-hand angle grinder is a heavy professional and semi-professional model that requires physical strength and a secure grip to work effectively and safely. It is good if the handle / handles of any angle grinder have a rubberized coating or vibration damping system.

15 best grinders (angle grinder)

  1. The best angle grinder for a disc with a diameter of 115 mm
  2. The best angle grinder with a maximum disc diameter of 125 mm
  3. The best angle grinder for discs up to 150 mm in diameter
  4. Best angle grinder with maximum disc diameter of 180mm
  5. The best angle grinder for discs up to 230 mm in diameter
  6. Best Cordless Angle Grinder

Angle grinder with speed controller: power tool capabilities

selection of angle grinder 125 mm with speed controller

If the angle grinder does not have a speed control, can I install it myself?Most angle grinders (angle grinder), among the common people of Bulgarians, have a speed controller.

The speed controller is located on the housing of the angle grinder

Consideration of the various adjustments should begin with an analysis of the electrical circuit of the angle grinder.

The simplest diagram of a grinding machine

Advanced models automatically maintain rotational speed regardless of load, but tools with manual disc speed control are more common. If a trigger-type regulator is used on a drill or an electric screwdriver, then such a regulation principle is not possible on an angle grinder. Firstly, the features of the instrument suggest a different grip when working. Secondly, adjustment during operation is unacceptable, therefore, the rpm value is set with the motor turned off.

Why regulate the rotational speed of an angle grinder at all?

  1. When cutting metal of different thickness, the quality of work is highly dependent on the speed of rotation of the blade.When cutting hard and thick material, it is necessary to maintain the maximum rotational speed. When processing thin sheet metal or soft metal (for example, aluminum), high speed will lead to melting of the edge or rapid blurring of the working surface of the disc;
  2. Cutting and cutting stone and tiles at high speeds can be dangerous.In addition, the disc, which rotates at high speeds, knocks out small pieces from the material, making the cutting surface chipped. Over, for different types of stone, different speeds are selected. Some minerals are just processed at high speeds;
  3. Grinding and polishing is basically impossible without speed control.Incorrectly setting the speed, you can ruin the surface, especially if it is a paintwork on a car or a material with a low melting point;
  4. The use of discs of different diameters automatically implies the mandatory presence of a regulator.Changing the disc Ø115 mm to Ø230 mm, the rotation speed must be reduced by almost half. And holding an angle grinder with a 230 mm disc rotating at 10,000 rpm in your hands is almost impossible;
  5. Depending on the type of crowns used, stone and concrete surfaces are polished at different speeds. Over, with a decrease in the rotation speed, the torque should not decrease;
  6. When using diamond discs, it is necessary to reduce the number of revolutions, since their surface quickly breaks down from overheating.Of course, if your angle grinder works only as a pipe, angle and profile cutter, you will not need a speed controller. And with a universal and versatile application, the angle grinder is vital.

Typical speed regulator circuit

This is how the governor board assembly looks like

The engine speed regulator is not just a variable resistor that steps down the voltage. An electronic control of the magnitude of the current is required, otherwise, with a drop in speed, the power will proportionally decrease, and, accordingly, the torque. In the end, a critically low voltage value will come, when, with the slightest resistance of the disk, the electric motor simply cannot turn the shaft.Therefore, even the simplest regulator must be calculated and executed in the form of a well-developed circuit.

And more advanced (and, accordingly, expensive) models are equipped with regulators based on an integrated circuit.

Integrated circuit of the regulator. (most advanced option)

If we consider the electrical circuit of the angle grinder in principle, then it consists of a speed controller and a soft start module. Power tools equipped with advanced electronic systems are significantly more expensive than their simple counterparts. Therefore, not every home craftsman is able to purchase such a model. And without these electronic blocks, only the winding of the electric motor and the power button will remain.

The reliability of modern electronic components of the angle grinder exceeds the resource of the motor windings, so you should not be afraid of purchasing a power tool equipped with such devices. The only limit can be the price of the product. Over, users of inexpensive models without a regulator sooner or later come to install it on their own. The block can be purchased ready-made or made by yourself.

Smooth start

The function is needed for safety. Both for you personally and for the entire power grid. Just imagine: you turn on a typewriter, which is designed, for example, for 11,000 revolutions. At the same time, the disc immediately starts spinning at a breakneck speed. Is it good? The consequence is a sharp jerk, a traumatic situation, an instant load on the gears. And the gearbox won’t say thank you for that.

With this function, the cranking time of the motor increases, which favorably affects the operation of the tool.

In which class to look: semi- and professional, household

We cut concrete correctly: dust protection

Any angle grinder in tandem with a specific attachment can cut metal. Whatever you take. Yes, and dealing with concrete is not a problem, only a lot of dust flies, and not only in the eyes, but also directly into the device. Micro- / macroparticles settle on the rotor (anchor), as a result, the service life is significantly reduced, as well as the service life.

The manufacturers wondered: shouldn’t they invent an “armored tank” for such cases? This is how the armature winding reservation appeared, or in simple words. The protection of the engine part by pouring resin or installing gratings, which forms a “shell”.

Protection can be partial. In semi-professional models and complete. When, in addition to the electric motor, bearings and gears are also hidden, and plugs are installed outside the case, which is very similar to a tank.

When working with concrete, the probability of getting dust particles in the eyes reaches 99%. Therefore, it is useful to have safety glasses for safety. They also use respirators and special gloves.

Apart from this feature, which, again, is not found in every angle grinder, there are other ways to collect dust.

Connecting a vacuum cleaner

Yes Yes. An ordinary vacuum cleaner with which you clean an apartment can just as well pull dust “in hot pursuit”, that is, straight from under the blade. To implement this tempting scheme, you will need an overhead casing with an outlet for the vacuum cleaner pipe (it clings to the base of the native casing).

In this case, it is important to monitor the degree of fullness of the container or bag, as well as stock up on replaceable filters.

Ideally, for these purposes, connect a construction vacuum cleaner. There is often an auto-on function in unison with an angle grinder. By the way, at the end of the work, it is recommended to keep any vacuum cleaner in tension, since the dust continues to spread for some time.

Another the simplest folk way. If you have an ordinary angle grinder without dust protection, but you really need to cut a couple of strobes in the wall, wrap a stocking, rag or any other fabric around it. This will partially block the ingress of concrete chips into the holy of holies of the mechanism. The only thing is to monitor the condition of the rag and change it periodically. If this is not observed, then you can burn the instrument, do you need it?

Additional electronic functions

For homework, do not flatter yourself with electronic bells and whistles. Some of them are available only in the professional line, but still there is something in the household segment.

Disk rotation speed

In angle grinders, the rotation speed of the working shaft varies from 2.5 to 12 thousand revolutions per minute. The working range is in the range from 3000 to 6000 rpm. As a rule, the manufacturer sets the optimum rotation speed for his machine depending on the motor power, and sets this parameter at the design stage.

High-end angle grinders are equipped with a working shaft speed regulator. This adjustment is especially relevant when changing discs frequently. For example, when a disc with a diameter of 230 mm rotates at a frequency of 10 thousand rpm, it will be very difficult to hold the tool in your hands.

Angle grinder motor power

The more engine power, the more force the tool develops, the more dense materials it is able to cut. With increasing power, the weight of the device increases. The industry produces tools with motors from 0.5 to 3 kW. For home and summer cottages, it is recommended to choose an angle grinder with an engine power of 0.8 to 1.2 kW. The more powerful mechanism is more difficult to hold in your hands, it consumes more electricity during operation.

A professional tool is designed for long-term operation, it has a higher service life. If large-scale construction is planned in the country, cutting steel bars, assembling formwork. You can use a tool with a motor up to 1.5 kW.

Additional features

Additional features offered by the manufacturer will make working with an angle grinder convenient and safe:

  • Smooth engine start. A very useful function. The disc spins up to working speed gently, without an “explosive” jerk at the start.
  • Automatic disk balancing. Reduces vibration of the instrument in the hands. Particularly helpful when using an unevenly worn disc.
  • Number of handles. For household grinders, as a rule, there are two threaded holes and one handle that can be rearranged. This is very convenient if you need to change your hand while working in order to get into a narrow place.
  • Rotation speed regulation. The electronic circuitry maintains a constant speed of rotation of the motor shaft, regardless of the load on the disc. The work goes faster, the motor and gearbox will last longer.
  • The presence of a dust protection system. An important function for concrete work. The gearbox and shaft are protected from the ingress of cement particles, increasing the service life of the tool.
  • Possibility of connecting a construction vacuum cleaner. Along with personal protective equipment. Respirator, goggles and gloves. It increases the comfort and safety of work. The workplace will remain clean.
  • Locking the start button. For extended operating conditions such as grinding or polishing, the operator does not need to keep the button depressed in the operating position.
  • Auto power off. If the light is turned off during operation, the machine cuts off the power to the tool so that it does not start itself when the power supply is restored.

Disk rotation speed

In angle grinders, the rotation speed of the working shaft varies from 2.5 to 12 thousand revolutions per minute. The working range is in the range from 3000 to 6000 rpm. As a rule, the manufacturer sets the optimum rotation speed for his machine depending on the motor power, and sets this parameter at the design stage.

High-end angle grinders are equipped with a working shaft speed regulator. This adjustment is especially relevant when changing discs frequently. For example, when a disc with a diameter of 230 mm rotates at a frequency of 10 thousand rpm, it will be very difficult to hold the tool in your hands.

Rating of popular models of angle grinder

Large angle grinder.

Inconvenient for making precise cuts, for example, cutting pores in welds on thin-walled pipelines. The 6.7 kg weight, like that of the GA9040RF01, is more difficult to control for the accuracy of the immersion depth. Cutting discs of large angle grinders start at 2 mm thick, as opposed to 0.8 mm for small 125 models.
Even a physically strong worker can hardly cope with the force of a jerk, when the rig is jammed. But the depth of cut up to 85 mm, in one plunge without turning the workpiece, can only be performed by large angle grinders, such as DWT WS22-230 D or Titan BSUM20230. Cutting through is more hindered by the dimensions of the case. You can go a little deeper by tilting the angle grinder, but the cut will no longer be perpendicular to the surface.

Small angle grinder 125mm Titan PSUM9125

One-handed models.

Professional, such as Makita GA5030 or AEG WS10-125, household, such as BauMaster AG-90122X or Dnipro-M MShK-980 differ from other tools. They have a short body: 250-280 mm; light weight: 1.5-2 kg; electric motor power: from 700 to 1000 watts, and girth: 175-190 mm.
The small diameter of the main handle, only 55-60 mm, with a tapered end, allows the small 125 mm single-handed angle grinder to be held even by a worker with a medium palm and short fingers.

A strong grip is reinforced with ribs on the non-slip plastic of the body, like in Einhell TE-AG 125/750, or with rubber pads, like in Vitals-Master Ls 1272HL.
To turn on without the help and interception with the second hand, the wide Start key is installed on the side and of the slide type, like in the Stanley STGS9125. It does not need to be felt, it is always in the area of ​​the thumb and thus the angle grinder can be operated even with a glove. To increase passive safety on small one-hand angle grinders, keys are installed with a shift force above average, like in Dnipro-M MShK-800.

This tool is useful for short cuts and localized grinding. For example, in a confined space under the bottom of a car, in the engine compartment, in an overhead position or standing on a ladder when the worker can hardly reach the object even with an outstretched hand.
Working with wire brushes with one hand is inconvenient because heavy rigs have a higher moment of inertia and skid.