Features and working of angle grinders

In a typical angle grinder, the power from the engine is transmitted to a gear head which has an abrasive disc that spins at a rapid rate. These discs can be of different types that are suitable for varied jobs involving different target materials. Some of these disc types include abrasive grinding discs, sanding discs, cut-off discs, wire-brush wheels, and buffing pads. Due to the extreme speed at which the wheel or the disc rotates, the force is projected laterally during cutting. To counter this torque, the Angle grinder incorporates large bearings.

The usage of the correct wheel/disc for different materials plays a very important part in the smooth functioning of the tool. Normally, for metal cutting, the grinder uses a depressed center wheel; for wood cutting, a flap wheel is used; and for stone cutting, a GC wheel is used. A hinged face plate with wing nut fasteners helps in easier wheel removal.

Sometimes, due to the extra pressure that needs to be applied on the surface to be cut, the grinder has a side handle, enabling the user to grip the device with both hands. To make the tool more efficient and to lessen the energy expenditure of the user, the power-to-weight ratio of the tool is increased. 

Another version of the angle grinderis a small grinder with a collet. It is generally used for blending, smoothing, and de-burring. This type of angle grinderis commonly utilized with carbide burr, mounted points, and sanding discs.

Some angle grinders have side brush caps to simplify brush changing. Productivity is further enhanced in some higher end angle grinders through an electronic power control that maintains the speed of the tool under all working conditions. The presence of an electronic start-up ensures a quick start of the device. The wire brushes that can be attached to angle grinders are useful for cleaning rust from the work surface and the buffing wheel is used for polishing. Moreover, the absorbing tool rest helps placing down the tool safely even as the disc is rotating at a fast speed, while coming to a stop.

The most common speed of the rotating wheel in angle grinder available today is 5,500 rpm and can go up to 7000 rpm; whereas, the speed of the angle grinderwith small grinding wheel rotates as fast as 19,000 rpm to 31,000 rpm. This high speed coupled with the operation of the engine can generate a large amount of heat in the tool and the vented metal gear case helps to dissipate the same.

What to look for in a angle grinder?

The most important factor while choosing a angle grinder is to decide on the right kind of grinder required for the work. The typical angle grinder with 6” disc is ideal for cutting, grinding, sanding, sharpening, rust removing and other applications. While opting for this type of grinder, one needs to consider the comfort Level of the user while in application. The rotation speed of the grinder is very high and kickbacks while in operation, which can prove to be dangerous. Look for the grinder with an impact absorbing tool, coated spindle housing that would not make the machine hot. Moreover, the body of the tool should be in such a way that the user can have a steady hold on it. angle grinders should be compatible with different types of wheel such as grinding and cutting wheel. Changing of the wheel should be extremely easy, consuming minimal amount of time and effort. Other accessories and features such as the cord length, wrench, arbor nuts, flanges, etc should be considered while purchasing. The hardened helical-cut alloy steel gear and shaft ensure longer durability of the tool.

If you opt for the angle grinder with small grinding wheel then the most important aspect to be considered here is the rpm. Also, consider the power-to-weight ratio while purchasing the tool. The collect capacity is the next feature of the grinder that needs to be taken into account. Usually the maximum collet capacity of these grinders is ¼ inch, but can vary. The power rating of angle grinders varies from 0.5hp to 0.8hp. Some reputed manufacturers of angle grinders include Chicago Pneumatic, Milwaukee, and DeWalt.