A home master always has a tool at hand: a drill or a puncher. But the drills wear out quickly and become dull. As a result, they have to be thrown away and searched for new ones in stores. But the real owner will save his time and try to figure out on his own how to properly sharpen a drill for metal and what tools will be required for this.
What are drills
They differ in metal and diameter. Their characteristics depend on their purpose for processing specific types of material: for wood, stone, metal. The latter type is the easiest to sharpen at home. Let's dwell on it. Each drill has 2 back surfaces that give the tool tip a conical shape and 2 cutting edges. If you put it on a horizontal washer, then the cutting edges will touch it, and the part behind them will lag behind them. It is located at a certain angle, which is called the "rear". The run-off should be approximately 0.2 mm for each inversion. All this you need to know if you are going to sharpen a metal drill with your own hands,for example, organizing a workplace in the garage. After all, when processing the tool, you need to give the correct shape.
How to organize your workplace
You will need a grinding wheel. But you can do without it. For example, adapt a power tool: a grinder with a rotating disc or an electric drill. The main thing is to install it on a workbench and fix it well. When sharpening, the quality of the metal changes (it loses malleability), and the drill heats up. To avoid this, you need to install a jar of water nearby. It will have to periodically immerse the machined tool. Machine oil can be used instead of water. Before sharpening metal drills, care must be taken to avoid injury. Eyes must be protected with special glasses, they will protect against chips and crumbs.
Sharpening
Beginning to process the tool, you must remember that it must be at the same angle. It is necessary to press the drill firmly against the grinding wheel. The process of sharpening on an electric emery consists of several stages. First, the tip of the drill is formed, then the cutting edge, and finally, the back surface is sharpened. Ideally, after processing, the back should be in the shape of a cone, and the cutting edge should be at the perfect angle.
When the main part of the work is done, it's time for fine-tuning. A professional master will be able to tell you how to properly sharpen a drill for metal. You can call him as a mentor. If youif you want to master this business yourself, then start experimenting with broken, blunt tools. As a result of processing, a jumper is formed. For drills with a diameter of up to seven millimeters, its length should be from 0.5 to 0.7 millimeters. In larger ones, it can be from one to one and a half millimeters. If the drill has a large diameter, then it is necessary to remove the edges on the shank. They experience great cutting resistance. To do this, you need to very accurately mark the circumference of the tool into three parts. Now on them you need to very carefully remove the metal to an equal depth.
Jump Processing
Another important point: you need to know how to properly sharpen a drill for metal and process a jumper. Most often at home on a grinding machine it is difficult to achieve the desired result. The ribbon is needed in order to reduce the load on the drill, increase the speed and accuracy of drilling. The overall process is as follows. The undercut of the jumper and the back face is made at the edge of the circle, at a slow speed. The drill should touch the sharpener for a short time. Then it must be taken to the side, turned one hundred and eighty degrees, again pressed to the circle. Periodically, if the metal heats up, the tool being processed must be dipped in water so that it does not lose elasticity. If you use a wet abrasive block, the risk of damaging the drill is greatly reduced.
Check sharpening
After the process is completed, it is necessary to check the quality of the work done, the symmetry of sharpening. Forin order to make sure how correct the sharpening of the drill for metal was carried out, you can arm yourself with a magnifying glass or use a drill. It is necessary to insert the processed tool into it and bring the felt-tip pen to the cutting edge. Then turn off the drill and check where the mark on the drill remained. If one side is more dirty than the other, then it needs to be sharpened. The second way is to drill plastic with a hand drill. On the side where more chips go, the edge of the drill is larger. She needs to be improved. After you succeed in sharpening the drill for metal correctly, you will receive a tool with restored working qualities. To keep them for a longer period, you need a box. To avoid damage, hitting each other or other objects, they should be wrapped in oiled cloth or tied with an elastic band.
