Drills for metal which are better firms. Which metal drills are better - selection criteria, types, brands and tips for storage and operation. Drill marking: deciphering the designations

It is often necessary to process various metal products not only for specialists, but also for home craftsmen. And here you can not do without special tools, in particular without drills. And here the question arises of which metal drills are the best and how to choose them.

Design and functional features

There is different types drills for metal, which differ from each other in functionality and design. At the same time, with the help of such devices it is possible to process not only the metal itself, but also other materials, for example:

wood;
ceramics;
polymer materials;
concrete;
brick.

Structural features must be taken into account material characteristics, which will be processed. If a we are talking about metal drills, they include elements such as:

cutting part - performs key work;
shank - with its help, the tool is fixed in the equipment chuck;
working surface - with its help, chips are removed from the processing zone.

Classification

Depending on the design of the drill for metal products there are:

spiral;
conical;
crowned;
flat.

flat tools differ in the flat shape of the working part, they are also called feathers. Their advantages are:

lack of sensitivity to distortions;
simple design;
affordable price.

However, they also have their drawbacks:

They cannot be used to drill large holes.
There is no automatic chip removal from the processed zone.

Spiral tools

Drill spiral type are the most common. Such a tool has the form cylindrical rod, the assembly of which are spiral grooves, covering its entire working part. Thanks to them, chips are removed from the working area.

Depending on the design and scope of use, spiral tools are divided into:

Cylindrical - have general purpose. The diameter of the tools can reach 80 mm, they can be used for both domestic and industrial purposes.
Left-handed - have a limited scope of use. They are needed mainly when it is necessary to drill a bolt with a broken head from a threaded hole or fastener, which can not be unscrewed in any other way.
High-precision tools - they can be identified by the presence of a designation, A 1. With their help, you can make holes with the most accurate diameter.

Core and cone drills

Core tools look like metal glass. On its end working part there are cutting teeth, with which you can make holes with a large diameter. Such teeth can be diamond-coated or made from hard alloys.

Conical products have stepped and smooth work surface and are used to create holes of small thickness. They are able to provide early light work hole centering. Their key advantage is the ability to make holes of different diameters.

There are also other types of tools, thanks to which even the most high-strength materials can be processed. These are cobalt or carbide tools.

cobalt tools made of high speed steel, which has been alloyed with cobalt. This material gives the drill a high strength, thanks to which it is resistant to thermal or mechanical influences and to deformation. With their help, even high-strength and ductile metals or alloys can be drilled. The only drawback is the high price, which is compensated by the technical characteristics.

If we talk about carbide structures, then they differ in that they put on their cutting part carbide inserts, and the main part is made on the basis of tool steel. The inserts are made on the basis of carbide alloys with high wear resistance and hardness. Cutting inserts will not need to be reground in the future, and with the help of such a tool you can drill especially hard metals or alloys, as well as products with a large thickness.

When choosing one or another option, you should know in advance where you will use it, as well as take into account the characteristics of the material being processed. When buying, consider such tool parameters as:

sharpening quality and symmetry of structural elements;
color;
functional features;
material characteristics;
working diameter;
conformity of the form to typical parameters.

When purchasing a drill for metal, it is necessary to take into account the features of the equipment with which it will work. For example, if you need to drill in a metal product big hole, you need to take a powerful low-speed drill.

Surface color specifications

The quality of the product largely depends on the color of the surface. What does this or that color mean?

Gray - such a tool is inexpensive and has not the most better quality. It has not been subjected to additional processing to help increase its hardness and resistance to combustion or deformation. When drilling hard metals, such a drill may not be enough even for one hole.
Black - the tool was treated with superheated steam, has increased strength and wear resistance. The cost is higher compared to the previous option, available to most buyers.
Light golden - the tool was subjected to a tempering procedure after manufacture, during which the residual stresses inside were eliminated and the strength characteristics were improved.
Bright golden - these instruments are the best, they contain titanium. During operation, the level of friction is reduced, due to this, the service life is long. The disadvantage is the high cost.

When purchasing a drill of one shade or another, think about how often you will use it, and also consider requirements for quality and accuracy of work.

So, if you plan to use them often and intensively for high-quality and fine work, then it is better to purchase bright golden models.

But if you buy cheaper options for this, then you will have to change them often, and in the end you will not save anything.

Dimensions

Manufacturers of these tools produce them in a large assortment in terms of working sizes. But to make it easier to understand them, you need to be able to distinguish them by series:

short series (length is from 20 to 131 mm, and diameter is from 0.3 to 20 mm, respectively);
elongated (length 19-205 mm, diameter 0.3-20 mm);
long (length 56-254 mm, diameter 1-20 mm).

Marking

To help with the choice of a particular product, its labeling will also help, which is not so difficult to figure out. Depending on the working diameter, it contains the following information:

If the tool has a diameter of up to 2 mm, there is no marking.
For models with a diameter of 2-3 mm, it includes information about the steel grade and the size of the cross section.
If the diameter is more than 3 mm, then the marking includes data on the steel grade, working diameter and an imprint of the manufacturer's logo.

This or that alphanumeric designation of the material grade indicates not only the category of the alloy, but also about the presence of additional components in it.

For example, the letter "P" means that the product is made on the basis of high-speed steel. If there is a letter "M", then this indicates that the composition contains molybdenum, and "K" indicates the presence of cobalt. These additional substances are designed to improve performance characteristics products.

Foreign manufacturers include in the labeling more information, in particular, the markings in them indicate the following:

country of origin;
trademark;
alloy grade;
working diameter;
accuracy class;
brief recommendations materials that can be handled by this tool.

Features of foreign markings

So, if we talk about the last point, which indicates the presence of recommendations on which materials are best processed with one tool or another, then such markings on foreign models are deciphered as follows:

HSS-R and HSS-G - the product is recommended for processing steel products made by simple casting or injection molding, and those made on the basis of alloyed or carbon steels with a strength of up to 900 N / mm 2, things based on metal alloys ( containing copper, zinc, nickel, aluminium, etc.) blanks based on malleable or gray cast iron.
HSS-G Co 5 - recommended for drilling metals up to 1100 N/mm2. These include stainless, carbon, alloy, thermal improved and resistant to heat, acid or heat types.
HSS-G TiAN / TiN - on the working part of such products there is a coating of titanium, aluminum and nitride. This increases their resistance to wear and corrosion, and the tools themselves can be used for processing metals with a strength of up to 1100 N / mm 2. These include malleable and gray cast iron, copper alloys, steel blanks made by casting.

What drills for metal are better

After considering the markings and characteristics of metal drills, let's move on to popular trademarks that are on the market. It is no secret that the service life and quality of work largely depend not only on the characteristics of the product, but also on the manufacturing company.

Experts advise to pay attention to such brands:

Brands of the CIS countries have high strength and reliability, are resistant to wear and differ affordable price compared to foreign counterparts.
Ruko - products can have a cross sharpening and different types spraying, they can be called best example ratio of price and quality of products.
Bosch - this brand speaks for itself.
Haisser - products of this brand have their own design features, special alloys are used for its manufacture. All this allows you to successfully use it even under extreme loads.
Zubr is a Russian brand that offers high-quality and reliable options at an affordable price.

Sharpening rules

If the cutting part of the drill is dull, then you need to sharpen it. Adhere to these recommendations:

Check if the sharpening device is working properly and prepare a container of coolant.
While sharpening, press the tool firmly against grinding wheel, start processing from the back of the cutting edge.
The processing angle depends on the material of manufacture. For steel, it is 140 degrees, for copper - 100, and for copper alloys - 120 degrees, respectively.
As a result of the work, all cutting surface, including the side, must be processed.

Since there are so many different drills for processing metal products on the market, sometimes you need to make right choice and it is extremely difficult to avoid mistakes in the work. This material will allow you to choose one or another version of the tool.

Drilling in metals is technological process aimed at getting holes different diameter in metal sheets and workpieces using a special rotating tool called a drill.

For the manufacture of drills, hard materials that do not collapse under mechanical action are used, most often these are high-speed alloyed alloys. Depending on the type and thickness of the material, the diameter of the hole and the technological requirements for the processing method, metal drills can be:

spiral;
feather.

Each type of tool has its own advantages and disadvantages, which significantly affect the ability to perform certain works, in detail about all these types.

Main indicators for selection

When choosing a tool for drilling metals, you must consider:

the composition of the alloy from which they were made;
method of additional processing and the presence of a surface coating;
manufacturer's trademark;
diameter and structural shape;
design and sharpening angles of the cutting edges.

Important! The cutting part of traditional twist drills has a front and back angle of inclination of the plane of the cutting part. The geometric parameters of the back angle of sharpening determine the magnitude of the friction force during operation and the wear rate of the tool. Increasing this value allows the machining of stronger metals, but leads to a decrease in heat dissipation and faster wear.

What can color say?

An important external parameter when choosing a drill can be the color of the surface, which indicates the composition of the alloy, the processing method and the surface hardening coating. High-quality tools are made of high-speed alloys with the addition of titanium, molybdenum or tungsten. The international designation of such metals is HSS (High Speed Steel).

However, even if the drill marking contains a similar inscription, but its surface is steel gray, you should not buy such a product. It was not subject to additional species processing and does not have sufficient strength and wear resistance. The price in this case will be low, but it will also last a short time, with the need for frequent sharpening.

Drills can be:

black, after heat treatment with superheated steam and additional hardening. The cost of a black drill is slightly higher than that of raw products, but it is quite affordable for domestic use. But the increased strength significantly increases the service life.
After heating the finished drills in a furnace and gradually tempering the metal to relieve internal stresses, the surface acquires light yellow tint . As a result, the wear resistance of the drill is significantly increased, and sharpening is required much less frequently.
Bright golden color talk about the use of an alloy with the addition of titanium, which is characterized by maximum strength. These are the most expensive drills, but their use is fully justified by a long service life.
Grey colour speaks of the low quality of the instrument. It is used for one-time work, after which it is thrown away. Accordingly, such a drill is the cheapest on the market.

When determining which drill will be the best for your particular situation, approach the issue with practical point vision. For continuous drilling work, it is better to buy an expensive, but more wear-resistant tool. But for periodic use and solving everyday issues, black or pale yellow drills are quite suitable. This will allow you to get the desired result at the lowest possible cost.

How drills are made and why they are of different colors, video from the RUKO factory (Germany)

Marking drills for metal, what to consider when choosing

The alphanumeric designations applied to the drill contain information about:

tool diameter and length;
brand of metal from which it is made;
method of additional processing and the presence of surface spraying;
manufacturing accuracy class.

At the same time, diameters up to 3.0 mm are not marked, and all the necessary information is given on the package.

The area of application can be indicated by the following symbols:

HSS-G for drilling soft steels, cast iron and non-ferrous metals;
HSS-E for high and stainless alloys;
HSS-TiAIN is a universal tool for all kinds of materials.

The presence of such a marking indicates the possibility professional use tool.

How to choose the right drill for metal and other materials

materials	HSS Co	HSS-Tin	HSS-G	HSS-R
Steel (H/mm2)<900	**	**	**	**
Steel (H/mm2)<1100	**	*
Steel (H/mm2)<1300	*	*
Stainless steel	**	*
Cast iron	**	*	*	**
Aluminum	**	*	**
Brass	**	**	**	*
Bronze	*	*	*	*
Plastic	**	**	**	**
Wood	**	**	**	**

Classification by length and diameter

According to the ratio of length and diameter, the tool differs in:

Short drills, 20-131 mm long, their diameter is in the range of 0.3-20 mm.
Elongated, length is 19-205 mm., Diameter - 0.3-20 mm.
Long with a length of 56-254 mm. and with a diameter of 1-20 mm.

TOP 10 most famous manufacturers

The trade brand of the manufacturer is also a very important factor influencing the right choice. Well-known manufacturers of drilling tools guarantee the strength of the alloy, the quality of sharpening, high wear resistance and corrosion resistance. Therefore, if you are looking for a high-quality drill for metal, then you will not be able to save money. The cost of well-known brands is quite high.

An exception to this rule may be rare drills made in the USSR. Seeing such a tool, you can be sure of its quality. Specialists unequivocally speak of the excellent performance of the Soviet tool in terms of alloy strength, long service life and stability of the cutting edges. This is also due to the requirements of GOSTs of that time for such a tool.

Among the top ten manufacturers of drilling tools, experts name:

European concern Bosch, producing drills from high-strength high-speed steel with a surface coating of titanium nitride with a tensile strength of up to 900 N / mm 2. Can be used for drilling any metal except aluminum and its alloys. The cost of a drill depends on its diameter and length. A set of 12 pieces costs an average of 3000 rubles.
Trade brand " Attack”, which is distinguished not only by high quality products, but also by affordable prices. They are made from high quality steel alloys that can provide a long service life even under conditions of high-speed metal processing. The average cost of one drill is less than 100 rubles. 5500 – 7000 Professional use kit.
Wurth Zebra Spiralbohrersatz HSS is one of the best twist drills for metalworking. Able to drill at high drive speeds while guaranteeing high edge quality and dimensional accuracy. Used for drilling structural steels and all grades of cast iron. Can be installed on stationary drilling machines and hand electric drills. The average cost of diameters up to 12 mm does not exceed 120 rubles per piece.
Sets of the Russian trademark " Encore". The set consists of 19 items with a diameter of 1-10 mm and costs an average of 1000 rubles, therefore it belongs to the group of inexpensive high-quality tools. The durability and reliability of the drill is ensured by the presence of a tip made of high-strength high-speed alloy.
German brand Metabo Bestler produces a spiral tool with a cutting edge sharpened at an angle of 135 degrees. This condition makes it possible to achieve high drilling accuracy even at any rotation speeds. The average price with a diameter of up to 12 mm is 100-120 rubles.
AEG HSS are considered the best drills for metal from an affordable price category. Special sharpening of the tool does not require preliminary punching on the metal surface, which greatly simplifies the workflow. Designed for drilling alloyed steels with a tensile strength of more than 1000 N/mm 2 .
Drills of the Russian brand " BISON» (ZUBR) is used for processing all types of steels and ferrous alloys. Special cruciform sharpening ensures self-centering of the tool and high drilling accuracy. A set of 20 items costs 1000 rubles.
Sets DeWALT can be used at production and household levels. The special design of the drill completely eliminates the possibility of damage and defects along the edges of the hole. A tool kit of 28 items with a diameter of 1-13 mm costs up to 5,000 rubles.
The surface of Hawera drills from a European company Bohler coated with titanium nitride, which increases their strength and wear resistance. In addition, all products are subjected to special grinding, which guarantees the quality of drilling at any speed of rotation of the drive. However, a set of 20 items can cost up to 6,000 rubles.
Irwin TurboMax is included in the category of a universal tool designed not only for processing metals, but also plastics, wood, gypsum and other materials. When drilling alloyed and stainless steels, a mandatory supply of coolant is necessary. The cost of a set of 15 drills is about 3000 rubles.

As can be seen from the list above, the drills offered for sale differ in their characteristics, purpose and price. The manufacturer's rating also determines the quality of products, which is usually confirmed by a large number of positive reviews.

Today, any hardware store has a wide selection of metal drills. Among the variety presented, it is important to choose exactly what you need. How to choose drills, whether you need to purchase sets, and much more that can help you make the right choice, read this article.

The drills with which I process metal consist of the following elements:

Cutting part (main work).
Shank (with the help of it there is a fixation in the cartridge).
Working surface (responsible for removing chips from the treated area).

To select the best and most suitable model, you should understand the types and shapes of drills. There are the following types:

Spiral. Drills of a cylindrical classical form, which are most often used for drilling metal. It is a cutting type of high quality steel. Differs in durability and durability.
1. Cylindrical general purpose. The diameter can be up to 80 mm. They are used both in production and at home.
2. Left hand spiral. They have a limited scope. For example, they are needed when you need to drill a bolt with a broken head or a fastener that cannot be unscrewed.
3. Drills of the increased accuracy. They are bought by those who want to achieve an excellent processing result. They are labeled A1.
Stepped (conical). The cutting surface has a cone shape. Used to make holes in thin metal - to eliminate defects in other cutting tools. With a high density of the metal, you should choose products with a golden color. The use of this type of tool in everyday life is rare.
Ring (crown). This is a cylinder with a cutting edge. The energy that is spent on making a hole with such a drill is low due to the small area of contact of the tool with the working surface. It is possible to drill large diameter holes with better edges than spiral models.
Feather (flat). They are a special kind of gimlets with interchangeable edges. With the help of them, high-quality, even holes are made. There is no distortion during the drilling process. It is also possible to change the diameter of the hole.
Cobalt. They are created on the basis of high-speed steel, which is alloyed with cobalt. It gives the product resistance to deformation (during mechanical or thermal action) and high strength. Used for drilling tough, high-strength alloys and metals.
Carbide. The plates of the same name are located on the cutting part of the drill. Tool steel makes up the main body of the tool. In the production of plates, carbide alloys are used, which are distinguished by high wear resistance and hardness. Needed for drilling especially hard alloys and metals, as well as products of great thickness.

Shank design

The shank is the part of the product that is clamped in the binding tool. They are divided into the following types:

Cylindrical. They are common, have the same diameter and base size.
Hexagonal. Designed for different models of drills.
Trihedral. For clamping in special chucks.
Conical. Needed for hand drills.
SDS and slotted. Designed for perforators, the range is diverse.

Drill manufacturing method

The drill can be made from a single piece of metal or alloy.

For the manufacture of the drill, soldering is used, during which the plates and tool holders are connected. For soldering, a special welding powder is used.

To reduce the consumption of expensive tool steel, improve product quality and reduce labor intensity in manufacturing, pressure treatment methods are used. After their application, a product with a shape and size of high accuracy is obtained, which makes it possible not to do further machining.

What shape the hole needs to be machined

The difference and purpose of drills is what task needs to be performed. According to the shape of the hole, they are divided into the following types:

square;
conical;
stepped;
cylindrical.

What are the drills covered with?

There are the following coverages:

oxide film. It has a black color, protects the tool from rust, overheating. Extends drill life.
Titanium nitride ceramic coating. Very durable, extends tool life by 3 times. Such a product cannot be sharpened.
Coated with titanium-aluminum nitride. More reliable than the previous one.
Coated with titanium carbonitride.
Diamond coating. He has no equal in strength.

Before you buy a drill for metal, you should familiarize yourself with the characteristics and design features of each type, and also adhere to the following recommendations:

Purchase a tool made of high speed steel, which contains tungsten and molybdenum. The presence of these elements can be found on the label.
Select the sharpening angle according to the type of material. For bronze, values \u200b\u200bof 130 ° -140 ° are suitable, for cast iron products - 118 °, structural steel - 116 °, stainless steel - 120 °.
Purchase products depending on the device in which they will be attached. Since fixation is carried out using a shank, close attention is paid to it.

Reference! If you do not want to understand the types and markings of products, you should contact a specialized store.

The main criteria for choosing: the desired diameter, the symmetry of sharpening, the strength and hardness of the product, the type of metal, manufacturer, price.

What does the color of the surface of the drill say?

The color that the surface of the drill has for metal is a parameter by which you can judge the quality of the tool:

Grey. Low quality, low cost. Additional processing is not needed.
Black. Treated with superheated steam for increased strength and wear resistance.
Light golden. Heat treatment, which eliminated residual stresses inside the tool, improved strength.
Bright golden. The best drills for metal, titanium is present in the composition. Reduced friction force. High price.

Size classification

A diverse dimensional grid suggests standards by which a drill can be classified into one category or another. These standards include GOST 886-77, GOST 10902-77, GOST 4010-77. These documents form 3 groups for the diameter and length of drills that are needed when working with metal:

Short. Drills 20-131 mm long, 0.3-20 mm in diameter.
Elongated. Length from 131 to 205 mm, diameter corresponds to the first group.
Long. Diameter - from 1 to 20 mm, length from 205 to 254 mm.

If you need to make a hole for a self-tapping screw, it is unreasonable to take a drill with a diameter similar to a self-tapping screw. To select a suitable model, you can use the tables that can be found on the Internet (dimensions of a sharp self-tapping screw with a press washer, for sharp self-tapping screws - black).

How to understand labeling

The designation contains the following letters:

A - used for 60° openings, there is a safety cone;
B - for 60° with fuse;
C - for 75°;
R - to get the shape of the arc.

There are also symbols that mean:

P9 - increased wear resistance and ductility, however, the product has low thermal tolerance.
P18 - high grindability for a wide range of hardening temperatures.
P6M5 - addition of molybdenum, drills have a tendency to lose carbon.
R12F3 - added 3% vanadium, the product has low grindability, designed for medium-duty work.
R6M5F3 - have a long service life.
R6M5K5, R9K5, R18K5F2 - contain cobalt in the composition, which guarantees hardness, heat resistance, as well as operation at high conditions.

Popular brands of tools from foreign manufacturers

For the accuracy of choosing drills from a foreign manufacturer, you should have an idea of the material that will need to be processed with their help. So, manufacturers recommend the following when choosing a tool with markings:

HSS-R and HSS-G. Tools (strength up to 1100 N / mm²) with this marking can drill products:

steel, made by simple casting and injection molding;
from alloyed and carbon steels;
from metal alloys, which include graphite, copper, zinc, aluminum, nickel;
malleable and gray cast iron;

HSS-G Co 5 (strength up to 1100 N/mm²). These became:

stainless;
carbonaceous;
alloyed;
thermally improved;
heat, acid and heat resistant.

HSS-G TiAN/TiN. If drills for metal have such a designation, this means that their working part is coated with a titanium-aluminum-nitride coating. It increases the resistance of drills to corrosion, wear, which affects the service life. This marking allows the use of products for metal processing with a strength of 1100 N/m². Manufacturers give recommendations on the use of such drills for processing:

gray and malleable cast iron, which contains graphite;
copper-based alloys (bronze, brass, cupronickel);
steel billets, which were obtained by casting.

As for popular brands, preference should be given to products from the following manufacturers:

Ruko. The drills that this brand produces are made with cross sharpening and have a different type of coating. They have good value for money.
Bosch. The name of this company speaks for itself.
haisser. Products of this brand successfully cope with the tasks set under extreme loads due to the design features and the use of special alloys.

In the modern world there are a large number of products designed to work with metal. For making a hole in metal, nothing can do better than a special drill. For this reason, it is so important to choose a product. When using low-quality products, you can harm the metal object and yourself.

The density of the metal is so high that it is necessary to use special tools and mechanisms to process it. In order to make a hole in this material, drills and drilling machines are used, in which drills are the main cutting element.

What are the best drill bits for metal? It is not easy to determine, because there are no universal products that would be suitable for processing all types of metal products. An experienced craftsman will be able to "by eye" determine the type of metal and quickly select the appropriate cutting tool for processing.

A beginner in this business needs to start from the basics. First, study the classification of drills and their scope, because the best models are products that are ideal for processing a particular type of metal.

What drills are, how to choose a product suitable for work by marking and appearance, find out in the article.

To choose the best models, you need to understand the types of drills.

Spiral

Classic, cylindrical drill bits most commonly used for drilling in metals. Usually spiral products are made of HSS steel.

The material is a high-quality cutting type of steel, so the gimlets made from it are distinguished by high strength and durability.

Conical (stepped)

The cutting surface has the shape of a cone, for which this type of drill got its name. Conical gimlets are used to make holes in thin metal, as well as to correct defects from other cutting tools.

The energy consumption for making a hole in this way is several times lower, due to the small area of contact between the tool and the surface to be machined.

The advantage of using this type of drill over others is the production of large diameter holes. At the same time, it is possible to obtain better edges than when working with spiral models.

Feather

A special kind of flat gimlet with interchangeable working edges is used for drilling metal. Such products allow you to make high-quality, perfectly even holes.

The absence of distortion during the drilling process and the ability to make a large diameter hole in various metal structures allows many craftsmen to refuse to use spiral products.

The low cost of spade drills in many cases of metal processing makes them the best for drilling holes.

These are the main types of drills used to make holes in metal structures.

Classification of drills according to the material of manufacture

Which drills for metal are the best for drilling particularly strong alloys, the answer is quite simple:

For processing such material, one should choose products in which a plate of increased hardness is located on the cutting edge. These gimlets are the best for cutting hard alloys.
The price of such products is low due to the fact that the main body of the cutting tool is made of ordinary tool steel.

Drills made of metal alloyed with cobalt have good characteristics.

They perfectly tolerate increased mechanical loads and excessive heating of the working surface during operation. The cost of products is high, but if it is necessary to make holes in carbide, then cobalt analogues are the best for doing this job.

Titanium drills are not inferior in strength to cobalt ones, and when drilling alloyed steels and non-ferrous alloys, they show even better results.

With proper use, titanium models retain factory sharpening for a long time, which will allow you to perform a much larger amount of work.

Inexpensive drills for metal are made from ordinary high-speed steel P9 and P18. The cutting tool does an excellent job of its function, but the working surface quickly becomes dull, especially when a certain temperature threshold is exceeded.

Marking of cutting products

Marking drills for metal is necessary to determine the type of steel from which the cutting tool is made. The product also indicates its diameter, accuracy class and manufacturer (country). Only spiral gimlets with a diameter of less than 2 mm are not marked.

In other cases, the marking of drills can have the following meanings:

P9 - made of high speed steel with a percentage of tungsten 9%.
Р9К15 - indicates the presence of cobalt in the amount of 15% in high-speed steel.
R6M5K5 - indicates the presence of a complex composition of cutting steel containing tungsten, cobalt and molybdenum.

Imported products have the HSS designation, which can be used to determine the composition of the material from which the drill was made. The HSS drill - the decoding of which will be given below, is used with an additional letter, by which the presence of an alloying metal is determined.

HSS Marking:

HSS-E - contains cobalt. It is used in the processing of high viscosity metals.
HSS-Tin - has a titanium coating, which significantly increases the hardness of the working surface, and the temperature resistance of the material increases to +600 degrees.
HSS-E VAP is a cutting tool used for processing stainless materials.
HSS-4241 - designed for drilling aluminum.
HSS-R - have maximum strength.

By marking the cutting tool, you can determine for which metal and in what mode the drill can be used. If the marking is not visible, then the purpose of the drill can be determined by the color of the product.

Visual identification of drill type

By the appearance of the cutting gimlet, you can determine the type of material from which the products are made and thereby find out the mechanical strength of the sample. By color, you can determine the composition and quality of workmanship.

Grey

Gray drills are made of metal that has not been subjected to any additional processing.

The quality of the tool, in this case, leaves much to be desired, but for a one-time use, such products will fit perfectly.

The black

This color indicates that the tool has been treated with superheated steam. In the process of processing, the product acquires greater strength.

It perfectly tolerates numerous cycles of heating and cooling of the metal, and also keeps the sharpening of the working surface for a long time.

The price of black drills for metal is not much higher than gray products, so if you have a choice, you should give preference to tools of this type when buying.

Dark golden

This color indicates that the cutting tool has been tempered. This type of processing significantly increases the mechanical strength of the product by reducing internal stresses.

A tempered drill can successfully process metals of increased strength, so if you have to drill too hard alloys, it is recommended to purchase a similar model.

Bright golden

The bright golden color indicates that the metal made with the addition of titanium was used in the production.

Despite the high cost of such models, it is much more practical to purchase a quality drill than to use cheap cutting tools that will need to be used in large quantities for complex jobs.

Thus, it is easy to determine the quality of products by appearance and decide which metal drills are better to buy.

Size classification

To choose the best drill and at the same time not overpay, it is enough to know what length sizes it is customary to divide these products into. If deep holes are not required when drilling metal, then purchasing models that are too long will lead to cost overruns.

Drills are classified according to length as follows:

Short, 20-131 mm long. Tool diameters are in the range of 0.3-20 mm.
Elongated, the length is 19-205 mm, and the diameter is 0.3-20 mm.
Long series with a diameter of 1-20 mm and a length of 56-254 mm.

When performing drilling work of various depths, you should select the tool that is most suitable for the specific task.

Top Producers

To purchase drills and be sure that the declared characteristics are fully true, you must choose the right manufacturer.

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

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

The best manufacturing companies:

1. Bosch - products of a German company have long proven themselves only on the positive side. Despite the rather high price of products, when purchasing Bosch drills, there is no doubt about the excellent quality. It is convenient and profitable to purchase the tools of this company in the kit.

Whichever set of drills you take, any will contain only the highest quality products that will last for many years, subject to proper storage and use.

2. Zubr is a domestic manufacturer whose products are optimized as much as possible in terms of price and quality. You can buy the products of this company both in a single copy and 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 attributed to the "endangered species". With due diligence, you can purchase a rarity, which is distinguished by unsurpassed technical characteristics.

The need to process various metal products arises not only among professionals, but also among many home craftsmen. When performing such processing, one cannot do without special tools, one of which is a drill for metal. On the modern market, you can purchase already completed sets, which include products of different diameters and lengths, or opt for a single copy that meets the required geometric parameters and mechanical characteristics. In both cases, the question arises of how to distinguish high-quality drills from low-quality ones and choose a tool that does not have to be changed after each processing cycle due to breakage or critical blunting of the cutting part.

Metal drilling is a labor-intensive and complex process that requires a responsible approach to the choice of cutting tools

Varieties and design features

There are various types of drills for metal, differing from each other in design features and functionality. It is important that with the help of drills designed for metal work, you can successfully drill holes in other materials, which include:

wood and materials based on it;
various types of polymeric materials;
ceramics;
brick;
concrete.

The design of drills for metal work is specially developed to solve certain technological problems and taking into account the characteristics of the material for which they will be used. That is why for those who do not know how, experts advise to get an idea of the design features of such a tool.

It is very important not to get confused in the variety of types of metal drills.

Drills designed for metal processing consist of the following elements:

the cutting part, which performs the main work of cutting metal;
shank, with which the tool is fixed in the chuck of the equipment used;
working surface responsible for removing chips from the processing zone.

Depending on their design, drills for metal processing are divided into several categories:

flat;
spiral;
crowned;
conical.

flat

Drills, the working part of which has a flat shape, are also called feather drills. Their most significant advantages are:

insensitivity to distortions, which any drill is subject to during processing with its help;
simplicity of design;
low price.

If you list the main disadvantages of tools of this type, then they should include:

inability to use for drilling holes of large diameter;
lack of automatic removal of chips from the processing zone (the device and geometry of such drills do not imply this option).

Spiral

Twist drills are the most common tool used to make holes in metal products. By its design, a twist drill is a cylindrical rod, on the side surface of which spiral grooves (one or two) are made, covering the entire working part of the tool. It is precisely such elements of a twist drill, such as helical grooves on its side surface, that ensure the removal of chips from the drilling zone.

Depending on the design and purpose, a twist drill may belong to one of the following categories.

Cylindrical drills for general metal work. The diameter of the drills included in this extensive category can reach up to 80 mm. They are actively used both in production and at home.
Left-handed twist drills with a very limited range of applications. They are indispensable in cases where it is necessary to drill a bolt with a broken head or a fastener that cannot be unscrewed in any other way from a threaded hole. There is a simple answer to the question of how to distinguish this type of drill from a standard right-hand drill: just look in which direction its spiral groove twists.
Drills of the increased accuracy. They are chosen by those professionals or home craftsmen who are interested not in a good, but in an excellent result of the upcoming processing. Tools of this type can be recognized by the designation A1. They allow you to create holes, the diameter of which is maintained with an accuracy of a fraction of a millimeter.

crowned

Drills of this type, made in the form of a metal cup, on the end working part of which there are cutting teeth, are used to create large diameter holes in the metal. The cutting teeth of such drills can be made of hard alloy or diamond-coated.

Cone

The category includes tools with a smooth and stepped working surface. Used to make holes in thin metal work, they provide easy centering of the hole at the very beginning of drilling, which cannot be said about a tool with a cylindrical working surface. However, the main advantage of using stepped cone drills is that with the help of one such universal tool it is possible to obtain holes of different diameters.

Among drills for metal, tools should be distinguished with which you can make holes even in high-strength materials.

cobalt

These are tools created on a base alloyed with cobalt. Cobalt gives the drill high strength, as well as resistance to deformation under thermal and mechanical stress. Due to these characteristics, cobalt-type tools are successfully used for drilling holes in products made of high-strength and tough metals and alloys. The rather high cost that cobalt drills differ in is fully justified by their characteristics.

Carbide

Carbide inserts are fixed on the cutting part of this type of drill. The main body of the tool is made of . For the production of inserts, carbide alloys are used, which are characterized by exceptionally high hardness and wear resistance. Using such drills, the cutting inserts of which are sharpened during the manufacturing process and are not subjected to further regrinding, it is possible to successfully drill especially hard metals and alloys, as well as thick metal products.

When choosing drills for metal, you must know exactly what technological tasks they will be used for, and also take into account the characteristics of the material in which you want to make a hole. To choose a tool that will meet your goals, you must also pay attention to the following parameters:

surface color;
sharpening quality and symmetry of structural elements;
working diameter;
compliance of the form with standard parameters;
characteristics of the material of manufacture;
purpose and functionality;
manufacturer's reputation.

When deciding which drills for metal processing to choose, the characteristics of the equipment with which they will be used should also be taken into account.

So, if you need to drill a large diameter hole in a metal product, for which powerful low-speed drills are used, you will need a tool that can be used with them.

What does the color of the surface of the drill say?

The color that the surface of the metal drill has is a parameter by which you can judge the quality of the presented tool. So, different colors of metal drills mean the following.

Grey

This color has the surface of the drills, which are of the lowest quality and, accordingly, the lowest cost. Tools with a surface of this color are not subjected to any additional processing that could increase their hardness, resistance to deformation and combustion. It should be borne in mind that when drilling hard metal, they may not be enough even for one hole.

Black

The surface of the drill acquires this color if it is treated with superheated steam. As a result of such processing, the strength and wear resistance of the tool increase, and, as a result, the resource of its use increases. The cost of such products is somewhat higher than gray ones, but it is quite affordable for most consumers.

light golden

This color means that the drill has been tempered after manufacturing. Such heat treatment allows not only to eliminate residual stresses in the internal structure of the tool, but also to improve its strength characteristics. Even in the photo, such a drill looks presentable and immediately inspires confidence in the quality of its workmanship.

Bright golden

This is the color of the best drills for metal, the material of which contains titanium. Due to the content of this element in the composition of the steel from which the drills are made, the level of friction decreases during their use, which has a positive effect on the duration of their effective operation. Naturally, drills with a surface of a bright golden color are quite expensive.

When choosing drills of a certain type, one should proceed from how often they will have to be used for metal work. It is also necessary to take into account the requirements for the accuracy and quality of holes that need to be created in a metal product.

For frequent and intensive use in order to make high-quality and accurate holes, it is better to choose more expensive, but also the highest quality bright golden drills.

Purchasing a cheaper tool will lead to the fact that it will have to be changed quite often, and this will negate the initial savings. Choosing more affordable types of drills, the surface of which is painted in black or light gold, is advisable in cases where you need to perform one-time work related to drilling metal.

Size classification

Modern manufacturers produce drills for metal work in a wide range of working sizes. In order to make it easier for the consumer to understand such a variety, the relevant regulatory document (GOST) provides for the division of metal drills into various types by size. So, the following categories of tools are distinguished:

a short series, the length of which is in the range of 20–131 mm, and the diameter is 0.3–20 mm;
elongated, the diameter of which, like the short ones, is in the range of 0.3–20 mm, and the length is 19–205 mm;
long series, the length of which can be in the range of 56–254 mm, and the diameter is 1–20 mm.

The classification of drills depending on their length and diameter is regulated by the provisions of several regulatory documents - GOST 4010-77, 10902-77, 886-77.

How to understand labeling

Marking helps to choose the right tool for drilling products made of metal. It's easy to understand her. The marking of drills, depending on their working diameter, contains the following information about the presented tool.

Miniature products, the diameter of which does not exceed 2 mm, are not marked at all.
The marking of drills, the diameter of which is in the range of 2–3 mm, contains information about the grade of steel from which they are made, as well as the size of their cross section.
The marking of drills for metal with a diameter of 3 mm or more contains the following data: working diameter, steel grade, imprint of the manufacturer's logo.

By the alphanumeric designation of the grade of the material of manufacture, one can get an idea not only of the category of such an alloy, but also of the content of additional substances in its chemical composition.

So, the letter "P" in the marking of drills for metal means that they are made of high speed steel. The composition of steel alloys used in the manufacture of drills for metal work may contain additional substances that improve their performance. Such substances, in particular, can be molybdenum, which is denoted by the letter "M", and cobalt, denoted in the marking by the letter "K".

Foreign manufacturers include more detailed information about the presented tool in the marking. Having decided to purchase such drills, you will receive the following data from their marking:

name of the country of origin;
trademark of the manufacturer;
grade of steel alloy;
tool working diameter;
accuracy class;
short recommendations on the materials that such a tool can handle drilling.

Popular brands of tools from foreign manufacturers

In order to know, when choosing foreign-made drills, which are best suited for solving certain technological problems, it is enough to have an idea of the material to be processed with their help. So, foreign manufacturers give the following recommendations for choosing a tool with a certain marking.

HSS-R and HSS-G

Using tools with this marking, it is recommended to drill:

steel parts made by simple casting and injection molding; products made of carbon and, the strength of which does not exceed 900 N / mm 2;
products made of metal alloys containing aluminum, graphite, copper, nickel, zinc (bronze, brass, cupronickel, etc.);
blanks from gray and ductile iron.

HSS-G Co 5

Drills with this marking can be used for processing metals, the strength of which reaches 1100 N / mm 2. Such metals, in particular, can be the following steels:

carbonaceous;
stainless;
thermally improved;
acid, heat and heat resistant;
doped.

HSS-G TiAN/TiN

If such a designation is present on drills for metal, this means that titanium-aluminum-nitride coating is applied to their working part. Such a coating significantly increases the resistance of drills not only to corrosion, but also to wear, which helps to increase their service life. Tools with this marking can also be used for processing metals and alloys with strengths up to 1100 N/mm 2 . Manufacturers recommend using the following types of drills for processing:

malleable and gray cast iron, in the structure of which graphite inclusions have a spherical shape;
copper-based alloys (brass, bronze, cupronickel);
steel blanks obtained by casting (including injection molding).

Top Producers

When choosing a tool for creating holes in metal, it is important not only to know what drills are, but also to understand the brands on the domestic market. The durability of the drill and the results of the processing that will be performed with it depend on who exactly produced the drill.

enterprises that produced drills in the territory of the former Soviet Union (their products, which are becoming smaller on the market every year, are distinguished by high strength, reliability, wear resistance and, accordingly, durability);
Ruko (drills produced under this brand can be made with cross sharpening and various types of spraying and are characterized by an excellent ratio of price and high quality);
Bosch (the brand itself, under which such drills are produced, already says a lot about their exceptionally high quality and reliability);
Haisser (drills of this brand, due to the peculiarities of their design and the use of special alloys for their manufacture, are able to successfully cope with their tasks even under extreme loads);
"Zubr" (under this domestic brand, affordable, but high-quality and reliable drills for metal work are produced).

How to sharpen

In order to qualitatively sharpen the drill in case of blunting of its cutting part, the following recommendations must be followed.