Drill – a universal tool, without which simply can not do when carrying out repairs of all kinds of complexity. To date, there are many kinds of drills, and therefore it is very important not to make a mistake and make the right choice so that later you do not have to replace or even throw out such a tool in case of its premature failure.
- Choosing a drill for metal
- Choosing a drill bit for concrete
- Drills for wood: how to choose?
Essentially all the drills differ only in their appearance (diameter and length), as well as with the material to work with which they are designed and, as a consequence, sharpened. Accordingly, it is necessary to initially choose the size of the drill (it is necessary that such a tool corresponds to the thickness of the material to be bored, or self-tapping screws, anchors, etc.). Next, you need to pick up drills depending on the work to be done.
Choosing a drill for metal
Drills for metal from conventional (meaning those that are used for processing wood) are distinguished by their versatility. Such a tool is indispensable when working with metals and with its help, it is possible to create holes in alloyed and non-alloy steels, cermets, cast iron and non-ferrous metals.
The most common today are spiral drills for metal. As a rule, such metal drills are a cylindrical rod in which two screw grooves are formed, forming cutting edges. These grooves are made at an angle of 10-45 ° to the axis of the cutting tool.
Pay attention also to the material from which the drill is made. To date, the most high-quality tool for metal processing is made from high-speed steel (for example, T11302 or M2) or allowed (for example, 150Cr14). These drills have increased durability and strength, and also provide the opportunity to achieve maximum results during operation.
Choosing a drill bit for concrete
Concrete is a strong and powerful material, which is very difficult to process, especially to drill a hole. As a rule, special drills with tungsten and cobalt hard alloy soldering (“win”) are used for drilling concrete. In addition, thanks to the use of modern technologies in the manufacture of cutting tools, drills made from modified tungsten-cobalt alloys have appeared on the market.
For the treatment of bricks or concrete, drills are used, in which the tips are soft or of medium softness. In the same case, if it is necessary to treat granite or other solid materials (for example, the same tile), then without using the winning drills with medium and high hardness plates (in addition, a series of teeth and reverse sharpening are performed on them) is simply indispensable.
Drills for wood: how to choose?
For the treatment of wood, the modern market offers the widest choice of highly specialised cutting tools. In particular, it is simply impossible to imagine working with a tree without using three basic types of drills:
- Spiral drills are sharply sharpened metal spirals, which are used to create holes in wood with a small diameter (from 3/8 “to 7/8”), but quite a significant depth (12 “-24” mm). Due to its spiral shape, such a tool is very easily removed from the working area after completion of work.
- Fountain drills are generally used in cases where it is necessary to create any blind hole in wood with a diameter of 3/8 “or more. It should be noted that such a drill can only be used to create holes since, in view of the absence of cutting edges On the lateral surface, it is simply impossible to ream the already existing one.
- Cylindrical (ring, core) drills are widely used to create large diameter holes (from 1 “). The main advantage of using such drills is the possibility of obtaining a neat hole without scoring and other defects, as well as high processing efficiency.
General recommendations when selecting drills
When choosing drills for work, it is necessary to pay attention to their appearance. The tool, if it is a question of really high-quality, should not have chips, dents, scratches and other defects. Cutting edges should be high-quality sharpened along the entire length and have a uniform color.
When choosing drills, regardless of the material for which they are designed, you need to pay attention to their color – it is easy to determine the final hardening treatment, which was carried out:
- Gray-steel – processing was not carried out.
- Black – the drill was treated with superheated steam for hardening.
- Golden – the drill has passed the processing of the release to relieve the internal stresses of the metal.
- Bright gold – on the surface of the instrument, a layer of titanium nitride is applied, designed to strengthen it and extend the service life.
It is not superfluous to note the fact that when choosing a drill, you need to pay attention to the company – the manufacturer. The best preference is given to eminent companies that are on the market for more than one year. Only, in this case, it is possible to avoid fakes and extra spending of money.