In construction and repair, tools such as a hammer drill, drills, screwdrivers are often used. They have a drilling function, and sometimes you have to deal with the problem of how to properly sharpen a drill yourself to extend its service life. There are ways to sharpen spiral drills that can be used at home, and for this it is not necessary to have a special machine.
Drills differ in the metal from which they are made, and the angle of sharpening. In its structure, the drill should be harder than the material for the processing of which it is used. As an example, consider a drill, the simplest in form - for working on metal. For sharpening, an electric tool with a rotating grinding wheel is suitable. To ensure the safety of the process, the tool is tightly screwed to the workbench and put on special glasses to protect the eyes. Before sharpening the drill, you need to take care of the presence of a container with coolant nearby, because when grinding it will heat up. So that the drill metal does not lose its qualities from overheating, it must be cooled. The angle of sharpening the drill is the angle that is formed by the cutting edges when viewed from the side. Since the twist drill has a tapered end, it has two cutting surfaces. Its back plane is rotated at a certain angle. When sharpening, it is necessary to control the position of the drill. Its rear surface should be 0.2 millimeters behind the rotating washer, and over the entire radius.
If you need sharpening a drill for metal or wood using an electric sharpener, then you should know that the process will take place in several stages. First, the back surface is formed at the drill, as a result of which its end should acquire a conical shape. After this, it is necessary to form a cutting edge, while being careful. After sharpening the drill, a jumper appears at its end. For drills with a diameter of up to seven millimeters, it should be equal to 0.5-0.7 millimeters. If the drills are larger in diameter, then the jumper can be from one to one and a half millimeters. At the end, final sharpening is carried out, as a result of which the rear corner of the drill is created. It directly depends on what metal the drill is made of.
The main difficulty of this method is sharpening a drill with seasoned angles. Experience comes with practice. They recommend using a goniometer, on which you need to set one hundred and eighteen degrees. If the drill was sharpened correctly, then when drilling it will leave chips from both of its spiral grooves.
Much less often than drills for wood or metal, they require additional processing of drill bits for concrete. However, there are some peculiarities. So, when sharpening a drill on a grindstone during severe overheating, it is not recommended to lower the drill into water, otherwise its plate may burst. It is better if it gradually cools down in the air. When sharpened correctly, the drill has straight cutting edges, and their intersection must coincide with the axis along which the drill rotates. If these rules are not followed, the drill will become blunt faster and there will be a risk of breakage.
When sharpening a drill, the process is better controlled with a washer. It should have a diameter less than that of a drill. When installing the drill in the hole of the washer, its leading edges should touch it and the rear edges behind it by 0.2 millimeters. Some rules must be followed. For example, when sharpening, you need to show maximum attention so as not to damage the cutting surface of the drill. To do this, leave 0.2-0.3 millimeters intact. The metal is removed from them last.
After reading this material, you should not be bothered by the question of how to sharpen the drill, and what rules should be followed. Now you do not need to throw out a dull drill, as you can cope with the problem on your own.