The arsenal of both home and professional craftsmen should have many different tools. Drills are indispensable for a whole range of work. Today there are many varieties. However, the twist drill is most widespread. This is due to a number of its features and functions. The device of this tool, as well as the scope of its application, deserve special attention.
General information
The drill is a cutting element of the tool that makes holes in various materials. There are many varieties of them. Select the type of cutter, based on the features and working conditions. By their characteristics, drills for a perforator, drills should be harder than the material.
The purpose of the drill is different. They can be used for processing metal, wood, concrete, glass, tile. Each tool, depending on the purpose, has its own characteristics.
The most widespread today is the spiral drill. It is also called screw. It has a cylindrical shape and has a number of design features.
Drill device
The twist drill has three main elements. This is the working part, the shank and the neck of the cutter. In the first section are two spiral helical grooves. This is a cutting element. They also take chips away from the workplace well. If the technique has this capability, it is through these grooves that lubricant is fed into the drilling area.
The working part consists of a cutting and calibration department. The latter is also called a ribbon. This is a narrow strip that extends the surface of the groove on the mill. The cutting section consists of two main and two auxiliary edges. They are located along the mill cylinder in a spiral. Also to this part include the transverse edge. It has a conical shape and is located at the end of the drill.
To securely fasten in the machine or hand tool, the cutter has a shank. It may have a foot for removing the drill from the socket or leash. The latter provides the transmission of torque from the tool holder.
The neck is needed to exit the abrasive wheel when grinding the working part.
Product Features
Drills for a puncher, a machine tool, which have a spiral shape, are the most popular today. This is due to their special characteristics. They are well directed in the hole, and also have a large reserve for regrinding. Due to the design features, this cutter removes chips well and easily supplies lubricants to the working surface. These features make the presented variety of drills very popular.
For the correct designation of geometric parameters, there are designations. The diameter of the drill can be very different. However, the designations remain the same. The tip angle at the vertex is referred to as 2Ο. The slope of the grooves is denoted by the letter Ο, and the end transverse edge is denoted by Ο. The rake angle in the drawings is referred to as Ξ³ and the trailing corner Ξ±.
Together, these metrics are called drill geometry. It reflects the position of the grooves, cutting edges, as well as their angles.
Tool varieties
The classification of cutters takes into account such an important indicator as the shape of the shank. It can be of the following varieties:
- Mill with a cylindrical shaft (GOST 2034-80).
- Drills with a conic shaft (GOST 10903).
- Tool with a tapered shank (GOST 22736).
In order for the master to be able to fulfill all the tasks assigned to him, the drill is released of various types. In the first embodiment, the cutter is mounted in a three-jaw chuck or other intended device.
Twist drill with a cylindrical shank can be made in short, medium and long versions. Such a tool has 3 accuracy classes: increased (A1), normal (B1) and normal (B). They can be made both welded and solid. The shank should not have annular cracks, lack of fusion or surface shells.
Conical varieties are mounted directly in the equipment spindle or adapter sleeve (if the size does not match).
Tapered shank
In the manufacture of mills with a tapered shank of the type presented, several different standards are used. Twist drill (GOST 10903) is applicable for products of normal length. This group also includes several other standards that are used in the manufacturing process of long, elongated cutters. These instruments can be issued with or without a neck. Moreover, its size is not regulated in any way.
The milling cutter with a tapered shank (GOST 22736) regulates the production of products with a diameter of 10-30 mm, which have a carbide plate. They can be made in shortened or normal form. The accuracy class for these products can be increased (A) and normal (B).
Drills with a tapered shank with a diameter of more than 6 mm are made by welding. For narrower sections, a one-piece type of manufacture is allowed.
Drills for metal
In addition to the breakdown of mills according to the principle of the shape of the shank, there is a classification regarding the processing material. The mill can be designed for metal, concrete, there is also a drill on wood. Spiral workplace is applicable for all varieties of material. The difference is only in the design of the tool.
Depending on the type of metal, the type of drill is selected . They are applicable to alloyed, unalloyed steels, cast iron, alloys, non-ferrous metals. Sometimes they are used for processing hard plastics. The durability of the use of the product depends on the thickness and hardness of the working area. This is a universal type of tool. A metal drill can fully drill a hole even in wood.
If the tool slowly sinks and heats the material very much, it is necessary to sharpen it. If its diameter does not exceed 12 mm, the procedure is carried out manually. But for larger cutters, special equipment is used for sharpening.
Concrete drill bit
One of the most difficult materials to process is concrete. It requires the use of tools with special welded carbide plates. They are called victorious. Today, any carbide tips are called that way.
Such a tool in the process of processing the material leaves holes with a diameter larger than the drill itself. This is due to his beating. If a drill is used, the drill shank may be cylindrical. A different type of mount is used for the hammer drill. It is called SDS. There are several types. Such a system allows you to quickly change the nozzle in the punch and other equipment.
Sharpening such drills is possible. However, care must be taken that the tool does not overheat. Otherwise, the carbide plate may fall off.
Wood drill
A suitable twist drill on wood is made of ordinary high-strength steel. Such material does not put forward serious requirements for the material of the cutter, its shape. This is the most ordinary drill. Quite simply, you can screw an ordinary self-tapping screw into soft wood or chipboard. You do not need to use a drill for this. However, there are situations where one cannot do without it.
If you want to make a hole up to 600 mm deep, you should use screw varieties of the cutter. Their diameter can be from 8 to 25 mm. Their length may be different. This is convenient if you need to make a through or through hole. If required, use an extension cord.
When drilling a drill after several revolutions, it is removed from the material and cleaned of chips. Then continue to work. Their length can be 300, 460 and 600 mm.
Having familiarized themselves with the main characteristics and the method of using such a tool as a spiral drill, everyone can choose the right variety for themselves. This is a very popular type of cutter. Their unique qualities, a wide range of applications make them very popular.