When choosing an electric emery, you should focus on the power, the number of revolutions per minute and the quality of the grinding wheels. For domestic use, emery of low power, with low revolutions and circles made of electrocorundum, may be suitable.
Electric emery allows you to quickly and easily sharpen knives, chisels, drills and other tools. It is an emery stone that is driven by an electric motor. A mixture of corundum and magnetite is used as an abrasive material in electric emery. The higher the corundum content, the more pronounced the abrasive qualities of the emery.
Usually, on one electric motor, two grinding wheels are located parallel to each other at once - one with larger particles of abrasive material, and the other with smaller ones. Accordingly, one circle is intended for a coarser sharpening, and the second for a finer one.
When choosing an electric emery, first of all you need to pay attention to a sharpener. There are professional, semi-professional and household grinding wheels. A household sharpener is not designed for long-term daily use (no more than two hours a day). A professional grade sharpener can be used for up to eight hours a day.
For sharpening tools at home, it is enough to use a household sharpener and a low-speed engine - up to 150 rpm. As a rule, in such emery circles are used with a diameter of no more than 20 centimeters and a thickness of up to 40 millimeters.
The most popular grinding wheels are made of aluminum oxide and are designated as "25 A". They do an excellent job of processing soft metal products - scissors, axes, steel corners, etc.
Grinding wheels 64 C are gray-green in color and are made of silicon carbide. They are designed for sharpening products made of hard metals and alloys. Such circles are not suitable for processing products and tools made of soft metals, since they cause an almost instantaneous appearance of dross.
It is also important to consider the grit size of the grinding wheel. The higher it is, the rougher the grinding will be. The smallest grain is marked with the number 8, and the largest - 40. Wheels with a fine grain are suitable for precise sharpening.
The higher the power of the electric emery, the harder materials can be processed on it. Now on sale are widespread sharpeners with a capacity of 120 to 400 watts. In everyday life, as a rule, emery with a capacity of 150 to 200 watts is used.
On store shelves, you can find electric emery from different manufacturers. The most popular brands are "Croton", "Energomash", "Zubr" and "Interskol" sharpeners.