The purpose of any drill is to create a different type of recesses and holes in a given material. This process occurs due to the rotation of the cutting element around its axis. In addition to creating new holes, with the help of these tools you can expand old ones that have a small diameter. According to their design, application and production method, all types of drills have noticeable differences. Let's consider them in more detail.
Classification by type and form of the working part
Due to the different types of tasks and functions, the elements have a different form of the working part and are classified as follows:
- Drill type screw. Its second name is spiral. It is the most common, because in everyday life they use it most often. This tool, the length of which is from 5 to 20 or more centimeters, will help in drilling both wood and other types of materials: metals, ceramics, concrete. The range of models of spiral tools is available in diameters from 0.1 mm to 3 cm.
- Flat drill. It has the shape of a pen. This feature gave him another name - feather. First of all, it is used to create deep holes of a relatively large diameter. The cutting element of such a tool is made in the form of a blade.
- To perform a deep drilling robot, long products that have two screw channels are used. Through them comes a special fluid that cools the tool during the work process. In most cases, the channels are placed inside the drill.
- There is also a view such as a single-sided drill. It is used only in cases where the future hole must be made with high accuracy. Due to the single supporting plane and the location of both edges for cutting on one side of the axis, the result of working with this tool is of high quality.
- Drill by type of ring. The structure of this type is interesting in that it is hollow inside. Thanks to this design, a narrow ring comes out during drilling. These types of drills have another name - crowns.
- To make a center hole, you can use the so-called centering product. It is in any hardware store.
As a result, we can conclude that there are various types of drills. And their purpose is also different. Let's look at ways to sharpen.
Types of sharpening drills
Having considered the types and shapes of work surfaces, it is necessary to disclose the issue of sharpening these elements. The process, or rather its form, is completely dependent on the tasks that will be performed by this tool.
The following types of sharpening are available:
- Ordinary, spiral. It is used for work with steel, non-ferrous metals, plastic.
- For cast iron. The name speaks for itself - for work with a mixture of cast iron.
- Cross grind at the edge. For all types of drilling work.
- With centering tip. For work with soft materials.
- Cone-shaped view with undercut.
- Processing with a pointed jumper and a main blade for adjustment. It is applied to strong steel.
Shank design classification
There is a classification of drills, the main criterion of which is the structure of the rear part - the tool shank.
According to this classification, the following types of tools exist:
- Cylindrical type.
- Cone-shaped.
- Faceted. With six, four or three faces.
- SDS products.
Production technology
Some types of drills are made of a solid metal billet. These include tools whose diameter exceeds 8 mm. Drills with a diameter up to 6 mm are made of alloys.
This is a special steel, which is also called high-speed. Those types of tools whose diameter exceeds 8 mm are made by welding. The shank of such products is made of an alloy of carbon steel. And the cutting part is made of high - speed alloy steel . For processing fragile and brittle materials (soft wood, some metals) a drill with carbide inserts is used. Such tools are equipped with grooves of various shapes. There are straight, screw and beveled types.
Hole shape classification
The shape of the holes produced is another method for classifying products. According to this characteristic, they are divided into the following types:
- Conical shape.
- Square.
- Stepped.
- Cylindrical.
Classification by Coverage
The material with which the drill is covered is a very important characteristic of the tool.
The coating determines the durability and effectiveness of the tool. According to this parameter, the following products are:
- The budget option for coating the drill is oxide film. The function of this coating is to protect the tool from corrosion and protect against overheating. Thanks to the oxide film, the service life is extended.
- Ceramic type coating. It is made from titanium nitride. Due to this, this type of coating increases the operational life of the tool by three times. But there is one drawback. It is forbidden to sharpen such drills.
- As a derivative of the past type of coating, titanium aluminum nitride was created. In this case, the resource of the drill increases by 5 times.
- Similar in effect to titanium aluminum nitride is titanium carbonitrade.
- The most durable and wear-resistant are tools that are coated with diamond spraying.
Types of metal drills
For work on non-ferrous metals, cast iron and steel, spiral products are perfectly suitable.
The chips that form during processing go through the grooved grooves. Drills for working on metal have differences among themselves not only in the material and coating from which they were made, but also in the type of shank. To determine the quality of the tool, you do not need to be a high-class specialist. Just look at the color of the coating. Poor quality tools have a gray tint. If the color of the product is black - this is a sign of a higher quality. A drill with a bright golden hue indicates that the tool is coated with titanium nitride and its quality is excellent. Speaking about the strength of the material itself, from which the drill is made, it can be noted that it should be carbide. After all, metals themselves have high strength. Therefore, for their processing, a material is needed whose strength will be greater.
For wood processing
When it is necessary to make several small holes in the material of wood, the simplest twist drill is suitable for this . For work of high precision or when you need to make a large hole, use special tools for working with wood. They are made of tool steel, carbon-containing or alloyed. For metal work such a tool is not used.
Types of wood drills:
- Spiral type.
- Helical.
- By the type of pen or feather.
- Crowns for wood processing.
- Forsner drill.
For work with concrete
To work with more durable surfaces (concrete, brick, stone) you will need a very strong product that has a solid tip. The alloy from which the types of drills for concrete are made has high strength characteristics. Work with such a tool is performed using shock-rotational mechanisms (perforator). Most often, SDS shanks are used for this type. To carry out a specific drilling, the types of drills need to choose the appropriate type. To make a small hole in solid concrete, it is necessary to use a drill in the form of a screw with a solid tip. For large openings, special carbide toothed crowns must be used. As a rule, they are coated with diamond spraying. This is necessary for greater efficiency and longer life.