For sharpening, the ripples exist special devices that help properly withstand all the working angles of this tool. But if there is no desired device at hand, it is easy to learn how to spend this responsible operation. Start practicing in sharpening is better with the minimum diameter of 10 - 12 mm.
A little theory
This is a drill sharpening angle, it is approximately 120 degrees.
After sharpening, the front cutting part of the tool must be symmetrical. If the displacement occurred, you need to fix it - drag.
Behind the cutting edge there is a rear section or rear surface. It should be directed relative to the cutting edge by 1 - 1.5 mm down toward the drill shank.
Preparation for the operation
On a grinding stone, the marker is applied parallel to the axis of rotation. Now we will try to correctly arrange the drill in space for sharpening. We apply the drill with the rear cut of the cutting edge to the drawing on the grinding stone, tightly without gaps. The drill must be located strictly horizontally!
At the same time, the inflicted feature will be somewhat above the axis of rotation sharpened.
The longitudinal axis of the tool in the horizontal plane will be rotated to the left of about 30 degrees, this will ensure the correct overall sharpening angle of 120 degrees. After writing this position in space.
Go to practice
We undertake the drill in the work, with knocked down cutting edges and try to sharpen it. We find the correct position of the tool in space, begin sharpening.
At first one side, then another. Do not hurry, we make work as neat as possible. If the lumpy lumps are overheated, it is spooled to red, dip the tool into the container with water. Then continue to work.
Check the result
As if everything turned out. The sharpening angle of about 120 degrees, the rear slice has the right bevel to the drill shank.
We take a drill, insert a sharpened tool into the cartridge. We try to drill a steel plate with a thickness of 8 mm.
Everything goes pretty good.
However, a true criterion for a properly performed operation is a chip of a spiral form. If it is also symmetrical two-sided, then it means that the angles of sharpening are optimal.