Types and characteristics of metal drills. Types of drills and their markings - we select a drill for any purpose! How to choose a good metal drill

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 also about much more that can help you make the right choice, read in this article.

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

Cutting part (main work).
Shank (it is used to fix it in the chuck).
Working surface (responsible for removing chips from the treated area).

To choose the best and most suitable model You should understand the types and shapes of drills. The following types exist:

Spiral. Drills of a cylindrical classical shape, which are most often used for drilling metal. This is a high quality cutting type of steel. It is characterized by strength and durability.
1. Cylindrical general purpose. The diameter can reach up to 80 mm. They are used both at work and at home.
2. Left-handed spiral. They have a limited scope. For example, they are needed when you need to drill out a bolt with a broken head or a fastener that cannot be unscrewed.
3. High precision drills. They are bought by those who want to achieve excellent result processing. They are marked A1.
Stepped (conical). The cutting surface has a cone shape. Used to make holes in thin metal - to eliminate defects in other cutting tools. If the metal density is high, 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 spent on making a hole with such a drill is low due to the small area of contact between the tool and the working surface. Can drill holes large diameter with better quality edges than spiral models.
Feather (flat). They are a special type of gimlets with replaceable edges. Using them, high-quality, even holes are made. There is no distortion during the drilling process. It is also possible to change the hole diameter.
Cobalt. Created on the basis high speed steel, which is doped with cobalt. It gives the product resistance to deformation (due to mechanical or thermal effects) 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 characterized by high wear resistance and hardness. Needed for drilling particularly hard alloys and metals, as well as products large 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 drills.
Triangular. For clamping in special chucks.
Conical. Needed for hand drills.
SDS and splined. Designed for hammer drills, the lineup diverse.

Drill making method

The drill can be made from whole piece metal or alloy.

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

To reduce the consumption of expensive tool steel, improve product quality and reduce labor intensity in manufacturing, pressure processing methods are used. After their use, a product is obtained with a highly accurate shape and size, which eliminates the need for further mechanical processing.

What shape of hole needs to be machined?

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

square;
conical;
stepped;
cylindrical.

What are the drills covered with?

The following coatings are available:

Oxide film. It is black in color and protects the instrument from rust and overheating. Increases drill life.
Titanium nitride ceramic coating. Very durable, extends the life of the instrument by 3 times. This product cannot be sharpened.
Titanium aluminum nitride coating. More reliable than the previous one.
Titanium carbonitride coating.
Diamond coating. It has no equal in strength.

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

Purchase tools made from high-speed steel, which contains tungsten and molybdenum. The presence of these elements can be determined by the labeling.
Select the sharpening angle according to the type of material. For bronze, values of 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 mounted. Since the fixation is carried out using a shank, close attention is paid to it.

Reference! If you don’t want to understand the types and labeling of products, you should contact a specialized store.

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

What does the color of the drill surface indicate?

The color of the surface of a metal drill is a parameter by which one can judge the quality of the tool:

Grey. Low quality, low cost. Additional processing need not.
Black. Treated with superheated steam to increase strength and wear resistance.
Light golden. Heat treatment, which eliminated residual stress inside the tool, improved strength.
Bright golden. Best drills for metal, contains titanium. Reduced friction force. High price.

Classification by size

A varied dimensional grid suggests standards by which a drill can be classified into one category or another. Such 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 with a length of 20-131 mm, a diameter of 0.3-20 mm.
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 unwise to take a drill with a diameter similar to the self-tapping screw. To select the appropriate 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 the markings

The designation contains the following letters:

A - used for openings at 60°, there is a conical fuse;
B - for 60° with fuse;
C - for 75°;
R - to obtain the arc shape.

There are also symbols that mean:

P9 - increased wear resistance and ductility, but the product has low thermal tolerance.
P18 - high grindability for a wide range of hardening temperatures.
R6M5 - addition of molybdenum, drills have a tendency to lose carbon.
R12F3 - 3% vanadium added, the product has low grindability, intended for work in medium conditions.
R6M5F3 - have long term operation.
R6M5K5, R9K5, R18K5F2 - contain cobalt in the composition, which guarantees hardness, heat resistance, as well as operation under high conditions.

Popular brands of instruments from foreign manufacturers

For precision drill selection from foreign manufacturer, you should have an idea of the material that will need to be processed with their help. Thus, 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 alloy and carbon steels;
from metal alloys, which contain graphite, copper, zinc, aluminum, nickel;
made of malleable and gray cast iron;

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

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

HSS-G TiAN/TiN. If metal drills have this designation, this means that their working part is coated with titanium-aluminum-nitride coating. It increases the resistance of drills to corrosion and wear, which affects their 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 blanks that were produced by casting.

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

Ruko. The drills produced by this brand are made with cross sharpening and have different type spraying. They have good value for money.
Bosch. The name of this company speaks for itself.
Haisser. Products of this brand successfully cope with assigned tasks under extreme loads thanks to design features and the use of special alloys.

IN modern world There is a large number of products designed to work with metal. For making a hole in metal, nothing works better than a special drill. For this reason, it is so important to choose a product. Using low-quality products can cause harm metal object and to myself.

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.

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. Taken average. 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. IN given value indicates the accuracy class of the device. It can be A1 - increased accuracy or B1 - normal accuracy. 2300 – operational and design characteristics, 7066 – serial number manufacturing. 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).

DIN drill markings have standard parameter 338 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.

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).
C – used for 75 degree holes without a safety cone.
R – for holes that have an arc different shapes.

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

Strength is indicated:

P18 is a satisfactory indicator, increased grindability, indicating a wide range of quenching temperatures.
P 9 – characterized by increased wear resistance, a narrower range of hardening temperature indicators, and increased ductility.
P6M5 – molybdenum is additionally added, increasing the tendency to decarbonization.
R12F3 – have reduced grindability, used for drilling in medium mode. Added 3% vanadium.
R6M5F3 – increased wear resistance, work on average speed cutting, used for carbon and alloy tool steels.
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. He points to possible meaning diameter

Conclusion

Each device must indicate the steel grade (P and number), additional elements included in the composition (M, K, F and the 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 symbol designs.

Drills and drill bits are the most basic tools in household, and almost everyone has it, and those who don’t know where to get it. Sooner or later, everyone will have to use a drill. Or if with wood or even stone everything is more or less clear, and you can drill a hole, so to speak, by touch, by feeling, then with metal this will not work. This is a very stubborn material. Let's figure out which metal drills are better?

Drilling is an entire art that can be studied and improved: drilling angle, pressure, but most of all, experience and the tool decide.

The problem is that most drills are sold of poor quality, especially in the markets. It is better to order online or in specialized stores where you can see and touch the material.

What you need to know about metal drills

There are a huge variety of metal drills; in addition to the fact that you need to look at the quality, you also need to pay attention to the shape and color. The product is built from the following elements:

The main (cutting) part, which performs cutting (drilling) of metal;
Working surface. Its role is that when the main part is working, chips appear, which are removed by the working surface;

Expert opinion

Sergey Yurievich

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The end, also called the shank, is attached to the drill chuck, and movement begins from it.

Metal drills come in many different shapes, each of which is used to certain type works

Depending on the form, there are the following types:

The most common type known to everyone is spiral. In essence, it is a cylinder-shaped rod, and on the sides there are one or two spiral grooves (it is because of them that the chips are removed). In turn, twist drills have their own subtypes:

increased accuracy, often chosen by craftsmen to make a hole perfectly, down to the millimeter;
classic ones, the same ones cylindrical, which are common among both pros and ordinary users;
narrow application, its spiral groove is wrapped to the left rather than to the right. It is used in cases where something needs to be drilled out.

Conical step drill. Unlike a cylindrical one, it can make holes of different diameters. Used to create new or expand existing holes.

Flat drill. As the name suggests - work surface of this type flat. The main disadvantage: due to its flatness, the chips are not automatically removed; you have to remove them manually. Besides, you can’t do it with this drill large holes. But despite the huge disadvantages, they are in demand because they are very cheap and insensitive to distortions during drilling.

Core drills have different cylinder shapes, but the upper part is devoid of a base and the sides are covered with teeth, which are made of hard alloy or coated with diamond dusting. Used to create holes of different diameters.

The following types differ in that they are created specifically for hard metal, while the previous ones are for metals with high density If they don't fit, they'll break.

Cobalt. Can be confused with spiral, since it also has a spiral shape, but unlike it does not have a cylindrical base. In addition, thanks to cobalt, this type has high strength. But they are also expensive, so not everyone can afford them; before purchasing, evaluate the difficulty of the work.
Carbide. They are caused by the presence of a carbide plate on the cutting part, due to which it can make holes in fairly dense metals.

These are the facts that can tell the shape and structure of the drill, but the color also matters:

Rarely found, but still existing bright gold drill bits. This color indicates the presence of the hardest metal on the planet – titanium – in the alloy. Which goes without saying about the quality of the part and its strength and value.
Light gold the color indicates that the product has undergone special thermal preparation. Not as durable and expensive as bright gold, but the price is quite high, not everyone can afford it.
Drill black color processed with superheated steam, thereby increasing its strength. The golden mean of price and quality.
WITH gray or metallic color– the most common and low-quality drills

Decide for what task you need a drill (what material needs to be drilled, what diameter of the hole), you can rely on this. Now you definitely won’t take a cobalt drill to make a small hole in thin sheet iron or vice versa.

Expert opinion

Sergey Yurievich

Construction of houses, extensions, terraces and verandas.

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When choosing a product, look at the sharpening, its symmetry;

The manufacturer can also play a role; the drills can be identical, but from different companies, in which case choose a manufacturer that you know or have dealt with.
To determine the working diameter, look at the marking, since on products up to two millimeters it is not marked at all, from 2 to 3 mm only the company’s mark is placed, and on products from 3 mm both the manufacturer and the working diameter are marked, so you should pay attention to this.

The variety of drills for hardened metal is huge, so there is no point in choosing, looking on the forum for which one is better, it all depends only on two things: the task that needs to be completed and the size of your budget for the purchase.

For those who carry out construction and installation work, the drill will be the best assistant. Inserted into a drill or others mechanical tools, it will drill a neat hole or tighten a screw.

There is no universal drill, and an incorrectly selected one will ruin the job or make it impossible, so you should carefully choose it. In most cases, you will have to select a drill yourself, because, unfortunately, not every seller in a hardware store will give the right recommendations on the quality of this tool and the work for which it is suitable.

Do I need to buy drill bits in sets? How do you know what shape a drill should be? What drills are suitable for? You will find answers to questions in the article.

Spiral – universal, suitable for any type of hole;
Conical - characterized by a smooth conical shape, suitable for holes of any diameter. Need constant supervision from a master;
Stepped – also conical in shape, but they make the process of drilling holes of a certain diameter easier due to the presence of steps of different sizes;
Core cutters (annular cutters) – for holes with a diameter of 12 to 150 mm, multi-layer materials. They are characterized by low cutting force and produce high roughness values that cannot be achieved with other types of drills. Suitable even for conventional drills. The shank must be strong and powerful to prevent slippage in the chuck. They are chosen depending on what kind of work is being done and what type of steel is being used. They differ from wood drills by the sharpening angle and the presence of two longitudinal grooves that divert the chips to the side.

Options in the photo

The most powerful drills for large holes
Due to the steps of a given diameter, such drills make it easier to drill standard holes. Working with a conical drill requires constant attention from the master. Twist drills are the most familiar and common

Professionals highlight 5 points general criteria choosing a drill for metal:

The type and characteristics of the metal you are going to work with, including the grade of steel;
Depth of “penetration”;
Type of drilling (through or penetrating);
Hole diameter;
What kind of tool do you use (hand or electric drill, varieties - hammer drill, screwdriver or drill), its general characteristics.

Please note that you should not buy a set of drills for household use. If you don't use drills for professional purposes, you won't need many tools and your money will be wasted. If you are going to buy a drill for permanent use, do not skimp.

Features of choice

Professionals choose drills based on the following criteria:

Material;
Blossom;
Labeling;
Sharpening angle;
Size;
Shank;
To the manufacturer.

It’s not difficult to identify them by eye, but before doing this, be sure to find out what type of drill you have. For example, large cross-section holes will require low-speed, high-power drills with appropriate drill bits. Additionally, please note that some types of drills are used only with cooling solutions, in order to avoid burning them and the metal.

Which material is better

To use a drill at home, it is better to choose one drill for working with metal various densities. When choosing a tool for working with aluminum and steel, focus on cost.

Cheap - Chinese-made products. They quickly break or become dull. For long-term operation they will be required in plural, and their total cost is disproportionate to the purchase of a single, but high-quality drill.

In search of a quality tool, turn to the products famous brands. They are made of solid steel and are solid rolled.

Drill highest quality- solid rolled

Counterfeits are determined by weight. The drill should not be too light.

Choose by color

On store shelves you can find drills in the following colors, which directly indicate their quality:

This does not mean that you don’t need to buy gray or black drills. Approach the choice from a practical standpoint - if you only need to drill a couple of holes, you can save money by buying several drills, and if you are planning more global work, it is better to buy a “golden” drill, which will last much longer.

Marking

All data about the drill is printed on its shank

The drill marking implies a certain combination of alphanumeric values and indicates:

Drill diameter;
Steel hardness;
Metal impurities in the alloy;
Technology and place of production.

Please note that markings are not placed everywhere - for example, drills with a diameter of less than 2 mm do not have them. On instruments domestic production with a diameter from 2 to 3 mm, a mark and cross-section are given, on products with a size of 3 mm or more - data on the cross-section, metal grade, impurities in the alloy, trademark. If you decide to buy imported drills, they will indicate the country of origin, brand of company and metal alloy, drill diameter and cross-section, accuracy class and recommendations for use.

The highest quality drills are characterized by the USSR marking.

Main types of marking:

HSS-R and HSS-G – suitable for working with cast, alloyed, carbon steel with a strength of up to 900 N/mm2, aluminum, cupronickel, graphite, bronze or brass alloy and cast iron;
HSS-G Co 5 – for processing metals with a strength of up to 1110 N/mm2, suitable for drilling stainless steel, carbon, alloy, non-heat-resistant, heat-resistant steel;
HSS-GTiAN/TiN – drills with titanium-nitride-aluminum coating, suitable for working with cast iron, brass, cupronickel and bronze, cast steel.

There are also drills made of cobalt (one of the most expensive and durable types of drills, suitable for drilling hard metals) and hard metal alloys (suitable for processing thick metals, have a one-sided, sharp sharpening angle).

Sharpening angle

The sharpening angle is the angle between the edges

The sharpening angle is the angle between the edges. For various types metal it is different. For example:

Drills for steel have a sharpening angle of 116-140 degrees;
To work with bronze, brass and aluminum, you will need a sharpening of 110-135 degrees (such drills are most common);
For “stainless steel” - 120 degrees;
For cast iron - 118 degrees.

The ease of drilling depends on how correctly you select the drill according to the sharpening angle. different types metal

What size are drill bits?

There are different sizes of drills, but our country’s GOST sets the following parameters:

Short (GOST 4010-77) – diameter 0.3-0.20 mm, length – 20-131 mm;
Extended (GOST 10902-77) – diameter 0.3-0.20 mm, length – 19-205 mm;
Long (GOST 886-77) – diameter 1-20 mm, length – 56-254 mm.

They allow you to make holes of different depths.

What is a shank and what are they?

The shank is the part of the drill that is clamped by the drill or hammer chuck. At first they were of the same type - tetrahedral, placed in the hole of the drill chuck and secured with a screw. Later, improved types of shanks appeared, used for various types of tools.

Shanks are:

Cylindrical - found most often. Typically, such products have same size drill base and diameter. Sometimes there are models in which the shank is thicker or thinner than a drill. The disadvantage is that the shank slips, which makes it impossible to transmit a large torque to the drill. Advantage - if the drill gets stuck in work surface, the drill will be protected from damage;
Hexagonal (aka hexagonal and hex) shanks - suitable for various types of drills. Disadvantage: insignificant accuracy when using a ¼-inch holder;
This shank shape fits almost any drill model
SDS shanks are the brainchild of TM Bosh for hot changing drills in rotary hammers. There are different types: SDS (with two grooves with a diameter of 10 mm, inserted into a 40 mm chuck), SDS-plus (common shanks with a diameter of 10 mm, placed into a 40 mm chuck, used on light hammer drills, drill diameter - 4-26 mm ), SDS-top (rare, have 2 open and 2 closed groove, characterized by a diameter of 14 mm, in a chuck - 70 mm, drill diameter - 16-25 mm, suitable for 4-kg class hammer drills with a replaceable chuck), SDS-max (widely distributed, suitable for drills over 20 mm, inserted into a chuck by 90 mm, diameter – 18 mm, have 3 closed and 2 open grooves), SDS-quick (4-10 mm), SDS-hex (used in jackhammers, picks, drills);
Shanks designed specifically for rotary hammers
Splined shanks – have the same parameters as SDSMax;
Triangular - clamped into three-jaw chucks, the main advantage is that they transmit large torques;

Metalworking does not cause difficulties only for those who know how and what to work with. Beginners in this business have to start with the basics, for example, finding out which metal drills are better or what shape of tip is needed for round holes.

There are not many special tools that can be used to work without the help of a machine. Therefore, it is important to understand what drills are, how they are classified and what they are intended for.

Metal drills: design differences and markings

The modern market offers big choice cutting tools for metal processing. You can purchase a ready-made universal kit or a set of metal drills.

For a one-time use, you should not pay for everything at once, but choose something specific for performing any operation that meets certain characteristics.

Tip: When looking at a tool, pay attention to the markings, where many parameters are coded. These are letters and numbers that all types of metal drills have.

From a short inscription, an experienced master immediately understands all the parameters:

metal fabrication;
what material to work on;
drill working diameter;
accuracy class;
country of origin (logo).

Spiral gimlets minimum diameter are not marked. But the rest of the designations cannot be understood by a beginner. House master. For example, the marking P6M5K5 indicates a composition with a certain percentage of tungsten, molybdenum and cobalt - this is the highest quality drill.

But also with 15% cobalt quality tool, in the designation P9K15 indicates that this is a high-speed steel drill.

Imported alloy steel products are marked with HSS:

HSS-E VAP (for working with stainless steel);
HSS-E with the addition of cobalt (for working on metals with high viscosity);
HSS-Tin with titanium (for increased cutter hardness);
HSS-4241 drills aluminum products;
HSS-R tool for maximum durability.

Attention: Look for the markings on the shank of the metal drill, as shown in the photo.

Which brand of drill is better?

To this day, home craftsmen have preserved tools and equipment from Soviet times. This is not to say that these were bad drills, especially Pobedit ones, but how to sharpen a drill for metal without equipment?

It’s easier to buy a new cutting tool from foreign and domestic manufacturers:

Bosch – any product of exceptional quality.
Ruko – Look for the best Phillips carbide drill bits for reliability.
Haisser - their drills with titanium-nitride coating can withstand extreme loads (processing steel, copper, bronze, cermets, etc.).
“Zubr is a well-established domestic brand, the optimal price-quality ratio, offering reliable cutters for metal, in particular with cobalt.

Important: Any drill will take a hole in a thin product made of a malleable alloy. For “specialists” working in metal, it is not profitable to buy cheap gimlets of dubious quality and spend time sharpening them.

As a rule, drills are specialized for metal and wood, but they can also work with other materials, including concrete, ceramics and polymers.

Drills, their types and characteristics

Drills that structurally have much in common are used for metalworking:

cutter;
working surface (provides advancement while removing chips);
shank (fixed in the chuck).

Main classification:

step or cone (conical) drills;
feather (flat);
crowned;
spiral.

You can find other types of metal drills in catalogs, but these are only discrepancies in the names. For example, annular cutters are the same core drills. On the end part you can see diamond-coated teeth. Standard core drills select the contour of the hole.

Step or conical drills – for holes required diameter in thin metal plates. The advantage is that there are several diameters in one tip, but they are practically not used in everyday life.

Classification by material

Cutting tools are most often made of steel, but when metalworking with hard alloys, the temperature rises. If the temperature threshold is violated, the drill becomes dull - you need cutters with plates of sufficient hardness, for example, alloyed with cobalt.

Titanium drills – good alternative cobalt for hardness and reliability. Technological use provides a guarantee long work with factory sharpening.

Carbide carbide tools demonstrate increased wear resistance. Although these drills do not require regrinding, this tool is used by professionals when working with thick metal. For these purposes they are used powerful drills operating at low speeds - drills are included.

From intensive use the tool loses its properties, but this does not apply to drills of a bright golden hue.

By the way, by the color of the drill you can judge its performance characteristics:

Black surfaces - from hot steam to increase wear resistance to extend the life of use.
Gray – drills for household use, after working with hard metal they become unusable.
Golden – high speed drills who passed special procedure hardened, they inspire confidence even in experienced craftsmen.
Bright gold surfaces are the best titanium metalworking tools, but they are quite expensive.

The dimensions of metal drills do not affect quality, but a wide range of drills makes it possible to choose the right tool for any metal work. The size scale is regulated by GOST standards. The working length of the cutters ranges from 20 mm to 131 mm, and their diameter ranges from 0.3 mm to 20 mm.