Which metal drills are best? We help you make a choice

Marking drills for metal

1. Twist drill markings
2. Center drill designation
3. Marking of the feather cutting tool
4. Conclusion

Markings for metal drills are special designations that are indicated on the cutting tool. It is imperative to pay attention to all the indicated numbers and letters in the marking, as they indicate the diameter of the device, the grade of steel from which it is made, the accuracy class, as well as the country of origin or brand of manufacture. Drills that have a diameter less than 2 mm are not marked; products whose size is from 2 to 3 mm are marked with diameter and steel grade. If the cutting tool is large (more than 3 mm), then all possible parameters are indicated on it. It is necessary to know the marking features in order to select drills of the required size, since not all devices are suitable for drilling certain holes. More detailed information is available on this website elengi.com.ua.

Twist drill markings: meaning of letters

Solid spiral cutting tools made of high-speed steel have the following grades: P 9, P18, P9K15. The letter P means that the product is made of high-speed steel. After the letter P there is a number that indicates the amount of tungsten that the tool contains. The average is taken. More letters and numbers follow. The numbers that are indicated after the letter indicate the content of the alloying substance in the alloy; this is a percentage parameter indicating the mass fraction of the substances. For example, if K6 is indicated, this indicates that the alloy contains six parts of cobalt, which helps to increase heat resistance. If M4, it means there are four parts of molybdenum. That is, after the letter P and the number, a special letter (the name of the element) and a number (the amount of the element present in the alloy) are indicated - this is the percentage content of the alloying element.

photo: marking of a twist drill for metal

For example, the following marking is indicated: Р6М5Ф3. This means that the drill is made of high-speed steel with the addition of 6 parts tungsten, 5 parts molybdenum and 3 parts vanadium.

Important: the labeling does not indicate the quantitative addition of chromium or carbon, since the first element has a stable parameter of 0.4%, and the second has a value equal to the vanadium content.

An example of a symbol for a spiral tool with a cylindrical shank.

A device that has increased accuracy, diameter - 15 mm, version 1, accuracy class A, designated: 2300-7066 A1 GOST 886-77. This value indicates the accuracy class of the device. It can be A1 - increased accuracy or B1 - normal accuracy. 2300 – operational and design characteristics, 7066 – manufacturing serial number. GOST - in accordance with what standards the device is manufactured.

If you purchase an elongated spiral drill with a cylindrical shank, then AB 2300-0055 will be written on it. AB is the enterprise index, 2300 is the operational and design characteristic, 0055 is the serial number of the standard size of the device according to the factory standard.

An installation with a conical shank has an indicator of 2301; for solid ones, the manufacturer’s trademark, diameter, grade of carbide, and the letter “T” must be indicated if the installation has increased accuracy.

Imported devices are designated HSS or DIN. The HSS device has an additional marking - a letter that indicates the working material. For example:

• HSS-Co (addition of cobalt);
• HSS-E (cobalt addition);
• HSS-G (addition of metal P4M3 - molybdenum);
• HSS-R (addition of metal P2M1 - molybdenum).

The marking of DIN drills has a standard parameter of 338 - this is a technical standard that fully complies with GOST 10902-77.

Center drill designation

The designation of centering drills is established according to GOST 14952-75. The designation has an additional letter A, B, C or R.

1. A and B indicate that the design is used for 60 degree openings and has (B) a safety cone or does not have one (A).
2. C – used for 75 degree holes without a safety cone.
3. R - for holes that have an arcuate shape.

photo: marking of a centering drill for metal

The installations have a designation, for example, 2317-0118 GOST 14952-75. 2317 is an operational and design characteristic, 0118 is the serial number of the standard size of the device according to the factory standard.

For example, if the number 0001 is indicated, then the diameter is 1 mm. Devices of group B have marking features. 2317-00-12 if this is the second version, and 2317-0113 if this is the first.

Group C is designated: 2317-0022 (second version), 2317-0124 (first), group R 2317-0027. This is if the diameter is 1 mm.

The marking of the p6m5 drill may not be indicated in this type of device.

Marking of the feather cutting tool

1. P18 is a satisfactory indicator, increased grindability, indicating a wide range of quenching temperatures.
2. P 9 – characterized by increased wear resistance, a narrower range of hardening temperature indicators, and increased ductility.
3. P6M5 – molybdenum is additionally added, increasing the tendency to decarbonization.
4. R12F3 – have reduced grindability, used for drilling in medium mode. Added 3% vanadium.
5. R6M5F3 – increased wear resistance, work at medium cutting speed, used for carbon and alloy tool steels.
6. R9K5, R6M5K5, R18K5F2 – cobalt is added, which provides increased secondary hardness, heat resistance, and increased cutting conditions.

They have the designation 2304 - operational and design characteristics. Full marking 2304-4001-50-108. The indicator from 50 to 108 may vary. It indicates the possible diameter value.

Conclusion

Each device must indicate the steel grade (P and number), additional elements included in the composition (M, K, F and number - percentage), the diameter of the drilling part, as well as the trademark of the manufacturer. In order to choose the correct size device, pay attention to these parameters, as well as to the design symbol.

About cobalt drills. Their review, alloy and characteristics.

Good afternoon. In this article we will write about drills, what kind of metal drills there are, their purpose and areas of application, as well as the alloys from which they are made. I’ll tell you right away what niche our company occupies - we sell tools for various purposes, including we import drills from China.

Metal drills come with different types of shanks. The most common of them are: cylindrical shank (c\x) and conical shank (k\x). There are also drills with a triangular shank and a hex shank.

Drills come in several series:

• The average series with c\x is described in GOST 10902-77.
• A short series with c\x is described in GOST 4010-77.
• A long series with c\x is described in GOST 886-77.
• Particularly long series - they are also called Extra long with c\x are described in DIN 1869. - Chinese standard.

If you carefully study these GOSTs, you will notice that they are all united by a reference to GOST 2034 - Technical requirements for drills. In GOST 2034, at the end of paragraph 1.2, the following is written: “At the customer’s request, it is allowed to manufacture drills from alloy steel grade 9ХС according to GOST 5950.” Those. Formally, drills can be made from any alloy.

The most popular are drills made of R6M5 alloy. What is R6M5?

Alloy R6M5 is otherwise called M2 (European name), HSS6542 - Chinese name.

Chemical composition of alloy R6M5 “W: 5.50-6.75; Mo:4.50-5.50; Cr:3.80-4.40; V:1.75-2.20;"

We often hear not the most flattering reviews about Chinese drills... Why does this happen? and what manufacturers and sellers hide behind this.

I’ll tell you a little about the standards and alloys that you buy and use not rarely, but most often.

The first place in cost in China goes to the HSS4241 alloy. Drills made from this alloy are available in “Black finish - black, not polished”, and they can also be ground (a little more expensive). In addition to the alloy, you can order a Titanium Nitride (TiN) coating - it’s also not that expensive, but the drill gets a marketable appearance for pennies. Another trick is Marking. The Chinese immediately warn that these drills are very cheap and can only be used on wood. However, this does not prevent the Russian importer from ordering the coveted “P6M5” marking. What kind of alloy is this? , the chemical composition of this alloy is “W: 1.50-2.50; Mo:0.60-1.20; Cr:3.80-4.40; V:0.50-0.70;" - which is translated into Russian designation as “Р2М1”. This alloy is very popular on the Russian market.

The second most expensive alloy in China is HSS4341. These drills are made in the same way as HSS4241 - they differ in different chemicals. composition in this case we get “W: 3.50-4.50; Mo:2.50-3.50; Cr:3.80-4.40; V:1.20-1.80;” - which translates into the Russian designation as “R4M3” - in terms of durability, these drills are significantly better than 4241. In terms of cost, they differ significantly from 4241. The buyer believes that these are good Chinese ones.

Third place goes to the alloy HSS9341. These drills are made in the same way as HSS4241 and HSS4341 - they differ in chemical. composition in this case we get “W: 8.50-9.50; Mo:2.70-3.30; Cr:3.80-4.40; V:1.30-1.70;” - which is translated into Russian designation as “Р9М3” - in terms of durability, these drills are almost like R6М5 (HSS6542). And the cost is almost no different from the R6M5. They are in very little demand in the Chinese market.

Fourth place deservedly goes to the alloy HSS6542 - P6M5. The execution is no different from its predecessors. The chemical composition is as follows: “W: 5.50-6.75; Mo:4.50-5.50; Cr:3.80-4.40; V:1.75-2.20;". They are popular in China, but they are brought to Russia much less than HSS4241 and HSS4341. The cost of these drills is significantly higher. Bringing these drills to Russia and honestly labeling them as R6M5 will be problematic due to the established market and this alloy simply cannot compete on prices.

The fifth place is occupied by the alloy “M35” - R6M5K5 or HSSCo, it is also a drill for stainless steel, it is also called a “cobalt drill”. This alloy has a new element - cobalt. Cobalt increases the heat resistance of the drill and also improves its mechanical properties. The design is slightly different from its predecessors; the Chinese do not coat them with titanium nitride - this makes no sense. The sharpening angle is 135°. Chemical composition “W: 6.00-6.70; Mo:4.70-5.20; Cr:3.80-4.50; V:1.70-2.00; Co:4.50-5.50;" , judging by the chemical composition, you can see that tungsten and molybdenum have a lower content tolerance - this means that the Chinese approach the manufacture of these drills more responsibly and with high quality than other alloys.

The sixth and last place is occupied by the M42 alloy. - R2M10K8. Drills made from this alloy are almost not represented on the Russian market, however, you can notice that Bimetallic Crowns are made from this alloy. Chemical composition “W: 1.15-1.85; Mo:9.00-10.00; Cr:3.50-4.25; V:0.95-1.35; Co:7.75-8.75;".

Chem summary compositions are given in the table

You can buy drills from us: Check out the availability and prices of drills by sending a request to our email address or call our phone number

A reputable supplier of drills should always have a chemical analysis of the drills. It is our custom to do a chemical analysis for each incoming batch and attach the results at the first request of the client.

There are many manufacturers of drills on the market. VIZ, Tulamash, TIZ and many others. We cannot say what alloy they use in the manufacture of drills, since we did not carry out chemical testing. analysis drilled them. In the near future we will compare drills from different manufacturers and post a video.

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Explanation of markings

Before you figure out what types of drills there are by model, you should pay attention to the markings. The designation is primarily influenced by the diameter. For thin products, marking is usually not provided; products starting from 3 mm are marked. As the thickness increases, the amount of information increases - accuracy classes, manufacturers, etc.

The alphanumeric designation is simply deciphered. By tradition, domestic products begin to be designated with the letter P, that is, high-speed steel. The next number indicates the percentage of tungsten. The following numbers and letters contain additional components and their quantities. So, K is cobalt, M is molybdenum. The greater the number of elements included, the better the characteristics (temperature, mechanical load) of the drill.

The content of carbon and chromium is not applied, because with the first the content is proportional to the amount of vanadium, and the second is always 4 percent. When the introduction of vanadium is more than 3%, the letter F and its amount appear.

Imported products are marked as DIN and HSS.

DIN designates multi-purpose tools suitable for normal and deep-hole drilling. They have different coatings, easily recognizable by color.

HSS have differences in the letters following the abbreviation. G - indicates the presence of a tool capable of handling carbon and alloy steel; it will process cast iron, aluminum, and copper alloy. E – a tool that can handle alloy/carbon steels, as well as acid-resistant and stainless metals.

Titanium steels are designated HSS-G TiN and HSS-G TiAlN. For them, any of the above metals will not be a hindrance.

Legend

Deciphering the chemical composition of steels classified as HSS is difficult, since their designation does not contain any detailed data. As a rule, catalogs for tools made from steels of this category contain information about the materials for which they can be used. In order to relatively accurately determine the chemical composition of HSS steels, it is necessary to use special equipment or solve this issue experimentally.

Most likely, this is a German analogue of high-speed steel HSS M2

H.S.S.

The letter R is often added to this abbreviation. These are drills that are characterized by the least durability. They undergo roller rolling and heat treatment.

HSS G

This designation is applied to drills whose cutting part is ground using Borazon (CBN). HSS G tools are the most common and are distinguished by their increased durability. In addition, a metal drill on which such a designation is applied creates the least runout when processing with it.

HSS with letter E

This designation indicates that the material used to manufacture the product contains cobalt. Tools with the HSSE designation are ideal for machining difficult materials and materials with high viscosity. As mentioned above, an analogue of the HSSE designation is the M35 marking. There are also international analogues of the HSSE designation (HSS-Co5 and HSS-Co8), which can be used to accurately determine how much cobalt is contained in the steel alloy.

Steel of this grade is extremely difficult to cut with a grinder

HSS G TiN

This designation indicates that the surface of the tool is coated with titanium nitride. Due to this, both the hardness of the surface layer of the product increases (by approximately 2300 HV) and its heat resistance (up to 600°).

HSS G TiAIN

The surface of the tool with this designation is coated with titanium nitride alloyed with aluminum. Thanks to this coating, the hardness of the surface layer of such a drill increases by approximately 3000 HV, and the thermal resistance by 900°.

HSS E VAP

Products with this designation can be used for. There is less chip sticking to their surface, so they break less often and provide high quality processing.

You can often find tools with the designation HSS 4241, which are used primarily for processing wood, plastic and aluminum products. As for the Super HSS designation, each manufacturer puts into it their own ideas about the quality of the tool.

The video shows a test of a knife made of HSS W18 steel.

Tools

Drills are a very popular tool not only in various fields of activity, but also in everyday life, in daily use. A very wide range of drills from different manufacturers sometimes simply confuses the average buyer. Let's find out how to choose a drill for metal and which manufacturer's drills should be preferred.

Content

1. Drills for metal Choosing a high-quality drill by color
2. Marking drills for metal

Metal drills

Metal drills are used for cutting holes in unalloyed and alloyed steel, cast iron, non-ferrous metal, etc. This type of drills has a spiral shape, hence the corresponding name - twist drills. Twist drills have two longitudinal flutes that guide chips away during drilling. There are several types of twist drill shanks - conical, hexagonal and cylindrical. Conical ones are inserted directly into the machine, cylindrical ones into a special chuck.

Features of different types of drill sharpening

The correctness of the chosen method depends on an accurate assessment of the wear of individual elements. The ones that suffer the most wear are:

• back or front surface;
• jumper;
• set angles;
• chamfered.

Depending on the degree of wear of one of the parameters or several simultaneously, a type of sharpening is selected that can eliminate these shortcomings.

To achieve a high-quality drilling result, it is necessary to correctly select the diameter of the drill and the shape of the cutting edge. To maintain it in working condition and give it the required shape, you should choose the right method (type) of sharpening.

The types used are designated by accepted abbreviations and are divided into the following categories:

1. NP - involves consistent grinding of the transverse edge. This allows you to reduce its length, thereby reducing the magnitude of external loads and increasing the period of normal operation of the drill.
2. NPL - this type involves processing the transverse edge and ribbon. Which leads to a decrease in the transverse size of the ribbon. This processing helps to obtain the required clearance angle. This reduces the friction force of the cutting edge on the metal surface;
3. DP - belongs to the category of double sharpening. Correct application allows you to get one transverse and four additional cutting edges.
4. DPL - this processing of metal drills involves sequential sharpening of the ribbon. As a result, better conditions are created for heat removal, reliability and durability are increased.

All types of processing are aimed at creating optimal conditions during drilling. Descriptions of the rules and characteristics of sharpening are established by the relevant standards. All parameters for sharpening a drill for metal are summarized in a single table. It shows the geometry of the cutting edge shapes used for various cutting conditions. The listed types of sharpening allow for high-quality restoration of the parameters of the cutting part of a tool with a diameter of up to 100 mm.

When applying the listed methods, it is very important to take into account the parameters of the metal from which the tool is made. This is necessary for the correct selection of a sharpening tool (grinding wheel)

For example, for high-quality restoration of drills made of high-speed steel, experts advise using an electrocorundum grinding wheel. If the drill is made of carbide materials, it is advisable to process it with a diamond-coated wheel. The operation of restoring parameters leads to significant heating of the part, especially its cutting edge. Therefore, this process must be carried out in stages using coolant.

Particular attention should be paid to restoring the basic parameters of the drill in a home workshop. It is necessary to ensure high quality of the following indicators:

• the same length of edges and ribbon (measurement can be made with an existing measuring tool);
• sharpness of both edges (check is carried out visually);
• values ​​of both angles (front and back).

To simplify the latter task, many craftsmen make their own templates that provide the required sharpening angle. Exact observance of these parameters and correct pointing of the jumper significantly increases the service life of the drill.

However, there are certain types of drills, the specifics of which significantly complicate the sharpening process. Problems with sharpening a twist or step drill are associated with the complex geometry of their design. Therefore, sharpening of such tools is carried out on special machines using developed equipment.

Sharpening step drills for metal is particularly difficult. Such sharpening can only be carried out using special tools and extensive experience. However, it should be noted that the majority of such tools cannot be re-sharpened at all.

Neither method is applicable to diamond-coated drills or other hard bits.

Types of drills - main parameters

Type and shape of the working part

1. A screw drill, also called a twist drill, is most often used in everyday life. With this tool, the length of which can reach 27.5 centimeters, you can drill both wood and other materials. Twist drills are produced with a diameter from 0.1 millimeter to 8 centimeters.

2. A flat drill shaped like a feather, hence the second name - feather, used for drilling large and deep holes. Its cutting edge is made in the form of a blade. It can be made in one piece, together with the shank, or it can be attached using a boring bar or a special holder.

3. For deep drilling. If you have to drill a particularly deep hole, the depth of which exceeds 5 drill diameters, use a long drill with 2 screw channels. A special emulsion flows through these channels, cooling the tool during operation. The channels are made either inside the drill or inside tubes soldered to the back of it.

4. Single-sided cutting drill. When the hole being made must have particularly precise dimensions, take a drill designed for cutting with only one side. It has a reference plane, and both cutting edges are on the same side of the central axis of the tool.

5. The ring drill is hollow inside. Due to this design, it drills only a narrow ring in the material. These are the so-called crowns.

6. To make a center hole in the part, use a special drill called a center drill.

Shank design

There are several varieties of the tail section of this instrument. Let's list them. So, the shank is:

• Made in the form of a cylinder;
• made in the shape of a cone;
• faceted, having three, four or six sides;
• SDS type.

Drill making method

The drill can be made of a single piece of metal (with a diameter of no more than 8 millimeters) or an alloy (with a diameter of up to 6 millimeters). In this case, a special steel called “high-speed” is used. Her brands: P9K15, P18 or P9.

If the diameter of the drill is more than 8 millimeters, then it is made by welding. In this case, the part that cuts is made of high-speed steel, and the shank is made of carbon steel.

When it is necessary to drill weak and brittle materials, use a drill equipped with carbide plates. It has grooves that can be straight, beveled or helical.

What shape of hole needs to be machined?

Depending on the task being performed, the purpose of the drills differs. So, according to the shape of the hole, they are divided into the following types:

• Conical;
• square;
• stepped;
• cylindrical.

What are the drills covered with?

1. The cheapest coating is a black oxide film. It protects the tool from rust and also protects it from overheating. The service life of the drill naturally increases.

2. Titanium nitride ceramic coating is very durable. It extends the life of the instrument by no less than 3 times. A drill coated with TiN cannot be sharpened, otherwise all its advantages will come to naught.

3. Drills coated with TiAlN - titanium-aluminum nitride - are of even higher quality and reliability. Moreover, such a drill can operate reliably 5 times longer than an ordinary one.

4. Titanium carbonitride, otherwise TiCN, is considered to be a coating of approximately the same quality.

5. When working with high-hard material, for example, porcelain stoneware or stone, you must use the most durable drills - diamond-coated. They have no equal in strength.

Straight Shank Drill

Home \ Drilling tools \ Drill with a cylindrical shank
Spiral drills with a cylindrical shank are used to create holes in various materials using mechanized hand tools, or less often, using stationary machines. Chucks are used to fasten such drills. GOST provides for the production of central drills with a diameter of up to 20 mm.

Twist drill from the main series GOST 10902

Twist drill with long series GOST 886

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Types of files for BOSCH jigsaws, features of their markings and purpose

TYPES AND FEATURES OF MARKING OF FILES FOR BOSCH ELECTRIC JIGSAWS.

Having worked with the Bosch brand for almost 20 years, we often encounter customer questions about the choice of jigsaw files and their features. Here are some of them: Which jigsaw file to choose? What types of jigsaw files are there and what materials are they suitable for? For which jigsaws other than Bosch are the files from this company suitable? Which saw blade shanks are intended for which models of electric jigsaws? What do the numbers and letters on the shank and blade of the file mean? What does the shank color mean? How to choose the length of the file for a certain material thickness? Which saw should I buy for ceramic tiles, rubber, porous concrete, plasterboard, plexiglass? Which saw cuts without chipping on the edge, regardless of the cutting side? Where are BOSCH saw blades made? Interpretation of pictures on file packages. And much more.

The best manufacturers

To purchase drills and be sure that the declared characteristics are completely true, you need to choose the right manufacturer.

Companies that value their reputation do not sell products of inadequate quality. Therefore, when choosing metal drills, you should give preference to manufacturers who have been on the market for a long time.

Among the newcomers, there may also be worthy producers. But in order to find out that a good quality product is on sale, you need to make a purchase, which often represents a “lottery”.

1. Bosch - products of the German company have long proven themselves only on the positive side. Despite the rather high price of the products, when purchasing Bosch drills, you can rest assured of excellent quality. It is convenient and profitable to purchase tools from this company as a set.

Whatever set of drills you take, each one will contain only the highest quality products that will last for many years, provided they are properly stored and used.

2. “Zubr” is a domestic manufacturer whose products are maximally optimized in terms of price-quality ratio. You can purchase the products of this company either in a single copy or in the form of a set. The latter option will significantly save money, despite the significant cost of the kit.

3. Soviet-made drills - this category of cutting tools can be classified as an “endangered species.” With due diligence, you can purchase a rarity that has unsurpassed technical characteristics.

Conclusion

Which metal drills are best to buy depends on many circumstances:

1. If you need to drill several holes in very thin and soft metal, then just buy a cheap drill that will do the job.
2. For professional use, it is not at all profitable to purchase cheap drills. Low-quality products can lead to defects and significant time costs for frequent replacement of low-quality cutting tools.

Characteristics

The technical parameters of manufactured drills depend on the color:

Black color - indicates increased wear resistance of the product;

A drill with a light golden hue means that the cutting tool does not have increased fragility; it was tempered during manufacturing to relieve internal stress;

Bright golden – the ability to reduce friction during operation, products are characterized by good strength;

Gray - the tool is designed for a short service life, the cheapest, of low quality.

Having remembered the color of the drill, we pay attention to the diameter of the working edge, which determines its marking. Small instruments (up to two millimeters) are not marked. The letter “P” is the very first letter, which means that high-speed steel was used in the manufacture of the drill.

The presence of alloying elements (titanium, cobalt, tungsten) will be indicated by the corresponding alphanumeric code adopted in accordance with GOST for marking.

All technical data about the drill can be read on its shank:

• What is the diameter?
• Learn about the hardness of steel;
• What alloying elements are in the alloy;
• Understand the technology, the manufacturer.

As mentioned, there are no markings on small diameter drills!

The most expensive, durable tool is made of cobald. Also, drills with USSR markings are most valued.

Primary requirements

Drills that are designed to produce centering holes are made from. According to the requirements of the regulatory document, this material must provide the following hardness parameters for the working part of the tool with a diameter:

• less than 3.15 mm – 63–65 HRC;
• more than 3.15 mm – 63–66 HRC.

A separate category of centering drills, the manufacturing material of which contains cobalt (5%) and vanadium (3%), must have a hardness that is at least one unit higher than the above parameters.

The diameter of centering type drills may have deviations, the limit values ​​of which are also specified in the regulatory document:

• for tools with a diameter over 5 mm – +0.15 mm;
• 2.5–5 mm – +0.12 mm;
• 0.8–2.5 mm – +0.1 mm;
• up to 0.8 mm – +0.05 mm.

Geometric dimensions of center drills

The regulatory document also lists the requirements for the condition of the surface of drills belonging to the centering type: there should be no cracks, nicks, tarnished colors or rough spots on it. It is accepted that tarnish colors may be present in the area of ​​the grooves - where the grinding wheel exits.

The standard also specifies criteria for failure of the centering tool, which for drills with a diameter of up to 3.15 mm occurs in the event of their breakage, and for a tool with a diameter of over 4 mm - in the event of wear of its rear surface by the amount specified in the relevant tables.

The difference in the width of the feathers must be within the following limits for drills with a diameter of:

• up to 3.15 mm - no more than seven hundredths of a millimeter;
• more than 3.15 mm – no more than one tenth of a mm.

The best manufacturers

When purchasing drills, it is important to pay attention to the manufacturer. In this case, the price justifies the quality, and the more famous the brand, the better the sharpening of the drill, the metal alloy, wear resistance and resistance to excessive heat. If you buy a non-disposable drill, do not skimp on the tool. For one-time work, cheap options are suitable.

For convenience, we have combined the characteristics of the main manufacturers into a table:

In stores you will find drills of different sizes and formats, different in hardness and colors, divided by sharpening angle, with different shanks and from a variety of manufacturers. In order not to make a mistake when choosing a drill, decide what you need it for now and whether you will need it in the future. If you follow these principles, buying a drill won't be a problem.