Each master has at hand such a reliable tool as an angle grinder. Using this device, you can not only perform high-quality material cutting, surface grinding, but also sharpen kitchen knives. Since for certain types of work a minimum rotation of the disk is required, it is recommended to purchase a device with speed control.
Angle grinder with speed control is a versatile and multifunctional tool that makes it easy to cope with any task in construction and repair. The main difference between such an angle grinder is the ability to independently set the speed of rotation of the disk, depending on the type of material being processed. Manufacturers produce a device with an electric motor, the power of which can be from 500 to 1500 watts. For cutting workpieces, you can choose machines with an average capacity of 800 watts, but if you plan to grind, it is recommended to give preference to more powerful models, since the area of contact with the surface of the processed material in this case is larger.
an angle grinder with speed control is absolutely safe to use, since all models are equipped with a full range of protective systems that prevent injury. We list the main ones.
- Soft start device. It is responsible for the smooth operation of the tool after pressing the start button. This device can also act as a limiter for inrush current, which extends the life of the device.
- Safety clutch. In the case when during the processing of material the disk of the angle grinder begins to “bite” or wedge, this device starts an emergency stop.
- Emergency brake. Performing processing of solid material, the tool can be twisted and pulled out of the hands. The brake helps to stop disk rotation in 3 seconds.
- Impregnation of the coil with a special composition. Since the cutting and grinding of the material is accompanied by the appearance of abrasive dust, its penetration into the device is prevented by the additional treatment of the coil with a protective layer. This avoids short circuit problems.
- Heat dissipating slots. Protect the device from overheating during intensive work.
- Balancing system. Circles of the machine may unevenly grind, after which shaking and beating of the apparatus may occur during processing of the workpieces. Smooth work helps a special automatic balancing.
- Overload fuse. When the cutting part is heated to a temperature above 160 degrees, the automatics are triggered, and the speed of rotation of the disc is initially reduced to 200 rpm, then it completely stops.
an angle grinder with a speed regulator weighs from 2 to 5 kg, their performance depends on the diameter of the disk and the number of revolutions. Mini-models that are suitable for working with circles of 115 and 125 mm are very popular with masters. Their speed ranges from 10,000 to 11,000 rpm. An angle grinder with circles of 115 mm is usually used for cutting material with a thickness of not more than 28 mm and is well suited for grinding wood, tile, porcelain and glass. Devices with 125 mm circles are considered the most demanded, since they cope well with grinding the surface of any material and cutting parts with a thickness of 30 mm. If it is necessary to perform cutting and grinding of steel pipes, bricks and concrete, it is recommended to use a device with a circle of 150 mm, while metal processing should be carried out at high speeds, and stone. at lower speeds.
The cutting disc is mounted in an angle grinder with speed control by means of a spindle stop and a protective key; in some models there is also a self-clamping system. Additionally, manufacturers also equip the tool with a casing that protects the craftsman from dust, sparks in the eyes and destruction of the circle on the go.
What is the adjustment for?
The quality of cutting and grinding of the material directly depends on the set speed of revolutions in the angle grinder. Since hard and thick workpieces lend themselves well to cutting at maximum speeds, and aluminum, on the contrary, can melt when heated, when working with them, you should adjust the speed of rotation of the disk. Management of operating modes is provided only in models equipped with a special regulator. This function is useful and used in several cases.
- When processing stone. This material is well cut and ground at low speeds, for each type of stone its own disc speed is separately selected.
- For finishing fragile surfaces that require careful handling. At high speeds, such products may deteriorate.
- When replacing one circle size with another. In this case, a speed adjustment is needed.
- When using crowns and discs with diamond coating. To avoid overheating and breakage, processing of the workpieces should be carried out at low speed.
Video: Angle Grinder 150 mm Adjustable
If the tool only plans to carry out rifled operations, then there is no need for a speed controller. In universal use, the angle grinder is indispensable. The system for adjusting the speed in the angle grinder is represented by integrated circuits. They are reliable in operation, operate with a soft start system and a tuned module.
Advantages and disadvantages
Angle grinders with speed control are on the construction market in a huge assortment. Depending on the design features and technical characteristics, they can have both pros and cons. So, household models are compact and light in weight, but their functionality is limited. In such a device, productivity is also reduced, during operation they quickly overheat and require constant stops.
As for professional tools, they are very powerful and endowed with additional functions that allow them to be used for a long time without overheating the mechanism. Such an angle grinder is of excellent quality, easy to operate and designed for both cutting and grinding of workpieces. The disadvantages of these models are the high price and heavy weight, since the device frame and additional components are made of durable material.
The main advantage of an angle grinder with speed control, regardless of their modification, is the ability to set a specific mode of operation. Thanks to this, the apparatus becomes multifunctional and allows the processing of various materials.
Models and their characteristics
Today, angle grinders equipped with speed control are in great demand among craftsmen. This type of tool is well suited for cutting, polishing and grinding workpieces. The construction market is represented by an angle grinder manufactured by both domestic and foreign companies. Well-established models of several brands.
- Bosch GWS 850 CE. This device is lightweight, which simplifies its management. The power of the machine is 850 watts, it is well suited for polishing marble and granite. The instrument comes with a six-position disc speed controller. The minimum speed of 2800 revolutions, the maximum of 11000 per minute, for processing wood the machine uses a special nozzle, designed for high speed. The manufacturer additionally equips the device with a handle, a key, discs and washers for attaching nozzles.
- Makita GA5030. This is the lightest grinding machine (its weight is 2 kg), which is designed for simple household work. Using the device, you can easily cope with the cutting, grinding and polishing of various materials. Thanks to the additional handle, the workflow is greatly simplified; disks with a diameter of 115 and 125 mm can be installed on this model. The tool has a power of 1400 watts, thanks to the speed control it is classified as a professional model. In addition, the angle grinder has a power-on lock, a stabilization system of revolutions, in order to protect the device from overheating, it is recommended to periodically turn it off during intensive work.
- Metabo WEV 10-125 Quick. This modification is available with the ability to change the speed and maintain a power of 1200 watts, the design provides an electronic engine protection system against overloads. The speed of rotation of the cutting wheel automatically changes depending on the type of work and is fixed at variable loads. Of all the 125-mm machines produced, this model is the best, it is characterized by a large number of revolutions and speed control. The angle grinder also has a safety clutch and replaceable brushes, which are disconnected when the voltage drops in the mains. In addition, the manufacturer supplemented the tool with an overheat indicator, stabilizer and a long cable.
Hitachi G13SS modification can complete the review of the popular angle grinder with speed control. Due to its high power indicators and the possibility of using it with discs with a diameter of 150 and 230 mm, it is highly rated among the types of equipment. The device is perfect for both repair and construction work. The machine can cut metal workpieces and grind parts from different materials. A distinctive feature of the device is its narrow grip and low weight, which makes it comfortable to use.
An angle grinder with a speed control is one of the most popular and widely used tools. Since this tool is represented by various modifications, it is difficult to make the right choice in favor of a particular device. The first step is to determine how the device will be used for domestic or professional purposes. In the event that infrequent and simple works are planned, then a small low-speed machine is suitable. For the simultaneous implementation of high-quality cutting and grinding of the material, it is best to opt for professional models.
In addition, it is worth paying attention to the following characteristics of the device:
- minimum and maximum speed;
- additional functions;
- drive options that can be used with the tool.
An important criterion when choosing is the frequency of operation of the device. For constant and intensive work, you need to buy models in which the outer case is made of durable metal and supplemented with brass inserts. When installing the pipeline, it is advisable to use devices with a maximum level of protection against water and dirt.
How to use?
Despite the fact that all models of the angle grinder with speed control are reliable, they still require proper care and operation. Therefore, it is periodically necessary to replace the working nozzles and contact brushes, add oil to the gearbox and clean the engine compartment of dirt. In addition, a technical check of the tool is also provided, it should be carried out at least once a month.
When replacing disks, the device must be turned off, the gearbox locked with the button, then remove the old nozzle and put in a new one, pressing it tightly with the nut. Oil filling is simple: to do this, remove the gearbox cover, having previously unscrewed the fixing bolts. As for cleaning the housing from dust, it is carried out using a vacuum cleaner.
Work with an angle grinder must be carried out in accordance with all safety regulations. The craftsman needs to wear protective gloves, goggles or a face shield. Do not start cutting the material with a broken or cracked disc, as it may cause injury. Grinding with a cutting disc is also not allowed, and cutting is cleaned.
For cutting and polishing various materials requires a certain speed of rotation of the disk, it can be adjusted using a special automatic system, which is controlled on the body by moving the lever. Thus, it is possible to easily reduce or increase the speed. In addition, you can lower the speed using large diameter discs.
See how to properly do-it-yourself the speed control of an angle grinder in the next video.