Drill material for metal. What are the best drills for metal. How to choose, an overview of manufacturers. What you need to know about metal drills

Not only professional builders, but also many home craftsmen periodically need to process various shaped parts. This work can only be done if there is suitable tool and a drill for metal of the desired section and shape. Those who often face the creation various parts for assembly metal structures, prefer to immediately purchase whole sets of drills for metal. For a single case, it is rational to buy only one type of drill. But in both situations, the question arises which metal drills are better, more reliable, stronger, so that they do not have to be changed after each individual block of work. You will learn about all the nuances of choosing such a tool from this article.

It is not difficult to understand which metal drills are better. Adhere to these criteria and familiarize yourself with the characteristics of the tool that meet these requirements:

shade;
quality and symmetry of sharpening;
diameter;
typical form;
quality and type of metal;
purpose and opportunities;
manufacturer.

Important! If you, before buying metal drills, clearly define your goal and indicate the price of the issue for yourself, choose right tool it will be very easy to work.

In addition to these characteristics, be sure to take into account the fact what kind of drill you have. For example, if you need to punch holes of a large cross section, you will also need drills of the same diameter and length, respectively, and only powerful and low-speed drills are suitable for this. In addition, some drills can only be used together with coolants so that they and the metal being processed do not burn out. An exception may be the situation when you act with smaller section drills sequentially, expanding the holes to the desired size in several stages.

Drill color

The first criterion by which you can independently determine the quality of the instrument offered to you is its appearance in particular the color. Experts note the following features:

Grey. If the metal looks exactly in this shade, then you are being offered the most unreliable option - these drills have not been subjected to any treatment to harden and increase resistance to deformation and combustion. Yes, the price of such a metal drill will be very low, but it’s good if you have enough of it to complete one task.
Black. If the drill is black, this indicates that it was treated with superheated steam. The result of this procedure is an increase in strength characteristics and, as a result, an extension of the service life. The price of such products is somewhat more expensive than gray color tools, but quite affordable.
Pale golden hue. This color is acquired by metal drills after tempering has been used in the manufacturing process. The main purpose of this treatment is to relieve internal stress in the hardened metal and increase its strength.
Bright golden color. These drills will cost you much more, but the alloy will contain the most durable titanium available today. Due to this, the friction of the drill during operation is reduced, due to which it is much more convenient to make holes, and its service life is extended.

Important! Determine which best drills for metal just for you, approaching the issue of purchase from a practical point of view. If you constantly need this tool, you should not save money - as a result, you will spend more time on the entire drilling process, on acquiring a new tool after a short time, and you will hardly be satisfied with your purchase in terms of the quality of the result. In this case, there is only one way out - to buy drills of a bright golden hue. For single work, cheaper black drills for metal or with a light golden color scheme are quite suitable.

Metal drill sizes

The size grid is quite wide, it may differ from different manufacturers in different parameters. But there is also a certain classification according to the current GOST, in which such groups of drills for metal are distinguished:

Short. This category includes instruments whose diameter ranges from 0.3 to 20 mm, and length - from 20 to 131 mm.
Long drill bits for metal. This group is represented by products with the same cross-sectional parameters as for short drills, but with a length of 19 to 205 mm.
Long. This category includes drills for metal, in which the diameter starts from 1 mm to 20 mm inclusive, while the length is 56-254 mm.

Important! All requirements meet GOST 4010-77, 10902-77 and 886-77, respectively, from the above list.

Drill marking for metal

The marking of drills for metal is determined by their diameter, as well as where they were made. You can note the following rules and features:

Drills with a cross section of up to 2 mm - do not have markings.
Drills with a diameter of 2-3 mm - on them you will find the designations of the steel grade and section.
From 3 mm - data such as cross-section, metal grade, including additional substances in the alloy, an imprint of the manufacturer are applied.

Important! Drill marking is an alphanumeric combination, which on quality products includes:

the letter P - the designation of high-speed steel;

alphanumeric combination - indicates the content of other metal impurities in the alloy, for example: M3 - molybdenum, K6 - cobalt.

Domestic manufacturers are limited only by these labeling rules. If you decide to buy metal drills of imported brands, you will find more detailed information on quality products:

name of the country of origin;
company trademark;
grade of steel or alloy;
section and size of the drill;
recommendations for use - metal that can be processed with one or another drill;
accuracy class.

Important! Imported drills are marked with HSS or Din values. To make it easier for you to understand these markings and choose the right tool for you, below are recommendations for using some of the most popular alloys with this marking.

Alloys, marking, appointment of drills for metal

You can figure out exactly what kind of drill you need if you know what kind of metal you need to drill. The manufacturer's recommendations are as follows:

HSS-R and HSS-G. Metal drills with this marking are designed for processing:
- steel - cast, die-cast, alloyed, carbon, with a strength of up to 900 N / mm²;
- metal alloys - aluminum, cupronickel, graphite, bronze, brass;
- cast iron - gray and malleable.
HSS-G Co 5. If this marking is on the drills, the strength index in this case is limited to 1100 N / mm². They are appropriate to use for steel:
- stainless;
- carbonaceous;
- thermally improved;
- acid and heat resistant;
- alloyed;
- non-heat-resistant.
HSS-G TiAN / TiN. For the manufacture of tools from this type of metal, titanium-aluminum-nitride coating is used. As a result, the surface becomes resistant to corrosion, perfectly cuts metal and can remain in its original form for a long time. They are suitable for machining alloys of various origins with strengths up to 1100 N/mm². The list of recommended metals includes:
- cast iron - gray, with spheroidal precipitates of steel, graphite, malleable;
- alloys - cupronickel, brass, bronze;
- steel - cast, including pressure.

In addition to these steel grades, other metals are also used for the production of drills:

Types of metal drills - body and tip shape

The variety of the current assortment of drills for metal is very large. To a greater extent, this happens because they are used not only for their intended purpose - for drilling metal, but are also often used for other types of work during processing:

wood;
plexiglass;
ceramics;
plastic;
concrete.

Important! Each of the types is suitable for a certain range of work due to the fact that the design is designed in a special way, taking into account all the nuances of a particular material.

Drill design

The main elements of the drill are:

cutting part;
shank;
working surface to remove chips from the hole.

There are 2 main groups of metal drills for these features.

Flat drills

Otherwise, they are called feathers. Models may differ in the shape of the sharpening of the cutting surface. Main advantages:

absolute insensitivity to distortions during the execution of work;
simplicity of design;
cheapness.

Flaws:

reduction in the diameter of the working surface during sharpening;
there is no automatic chip removal from the hole.

A commonly used variety is cone drills for metal. Present on sale individually and in whole sets with a cross section in the range of 6-60 mm. The conical drill for metal is more intended for use on special equipment - drilling machine or in a two-handed drill. The name stands for itself - the shank is sharpened in the shape of a cone. Great for making large holes.

Twist drills

These metal drills are more popular today and it is their varieties that are widely used. In shape, these are rods in the form of a cylinder, 1 or 2 grooves-recesses go over the entire surface. With their help, the chips from the hole are immediately, in the process of work, brought out. Depending on the shank with which the drill bit for metal is distinguished:

Ordinary cylindrical drills for metal - usually their diameter does not exceed 12 mm. Suitable for both professional needs and household tasks. This group is the most popular type of metal drills.
Core drills for metal. Drills for metal with such a shank are used when it is necessary to make a large hole - with a diameter of 30 mm or more. Such a tip looks like a crown with frequent teeth, most often designed in the form of a hexagon. These drills are more suitable for thin metal.
Threaded drill. This tool model has a direct purpose - the design of a hole with a thread of the desired section. The diameter of the drill itself is usually taken 1 unit - millimeter less than the cross section of the hole.
Step drills for metal. This type is universal in terms of the fact that with the help of one tool you can make holes of various diameters. The only caveat - it is recommended to use them only for sheet material, the thickness of which does not exceed 2 mm. The diameters of such drills for metal are up to 30 mm. Price - increases as the cross section increases.
Left hand drills. Their scope is limited - only for unscrewing hardware: screws, bolts, self-tapping screws.
Drills of the increased accuracy. These tools are chosen mainly by those who are very important for high accuracy of the result. The accuracy class is indicated by an alphanumeric combination - A1 or B1. The higher the accuracy class, the higher the price of metal drills.

Drill manufacturers

Very important point when buying drills for metal - the manufacturer. The fact is that good feedback consumers and optimal price are not all factors. The reliability and reliability of the brand affects the quality of sharpening, alloy strength, wear resistance, anti-corrosion and fire-resistant properties of the tool. Therefore, do not try to save much, give preference to trusted companies whose products will serve you to solve more than one problem.

According to reviews and market positions, metal drills are considered the best:

What else do you need to know about metal drills?

After a certain service life of any drill, it must be sharpened. This procedure can be done by hand under 2 conditions:

you have purchased a tool from a reliable manufacturer that does not save on the quality of the metal;
you follow the rules of sharpening technology.

You will be able to perform self-sharpening of the drill if you adhere to the following scheme:

Be sure to put on protective clothing before starting work - goggles, gloves.
Prepare containers of coolant. For this purpose, water or machine oil can be used.
Check that the grinder is working properly.
Press the drill firmly against the grinding wheel and grind the surface sequentially, starting from the back.
stick suitable angle sharpening:
- steel - 140 degrees;
- bronze - 120;
- copper - 100.
Process the working part of the drill, holding the sharpening angle.
Do not focus solely on the tip - the entire surface, including the side, must be well sharpened.

Important! Before you immediately sharpen the tool you need, first practice on those tools that you definitely no longer need. So you can fill your hand and do everything right on the drill you need.

Video

Watch the video, which clearly shows how you can sharpen the drill with your own hands.

Conclusion

Now you know everything about how to choose the right drills and which ones are best for your specific purpose. Consider all the criteria when buying a tool and then you will not have to worry about the need to purchase a new drill in the near future. It will serve you for a long time, and the quality of the work performed will meet the specified requirements.

For drilling cast iron, ferrous and non-ferrous metals, it is required to carefully select equipment and equipment with sufficient power. Drills designed to work with soft materials, will not be able to cope with metals. Work will be slow, finished holes will be of poor quality, and drills will be subject to excessive wear and require regular replacement. All these problems can be avoided if you decide which metal drills are better.

Main criteria

Universal drilling tool various materials does not exist, and even superficially similar metals can have completely different hardware requirements. High-quality drills from reliable manufacturers are quite expensive, but with the right choice they can serve for a very long time, while saving a lot of time and money at work.

When choosing a tool, you need to pay attention first of all to the following points:

If you make a choice, each time focusing on these points, the likelihood of receiving low-quality products is minimized.

Drill type selection

There are three main types of drills: spiral, stepped and conical (chisels). Somewhat less common is the fourth type - annular cutters, also called core drills. They are designed to create large holes up to 150 mm.

To decide on one Of the types among these options, you need to focus on the following selection criteria:

Required hole diameter.
Penetrating or through drilling is required.
Steel grade, product appearance and other features of the metal being processed.
Required hole depth.
Characteristics and features of the tool used for work: drill, screwdriver, puncher, etc.

You should not buy drills in whole sets if they are required in isolated cases and for domestic purposes: such an acquisition would be economically unjustified. For domestic purposes, it is desirable to purchase goods individually, for specific needs, and for professional purposes - in sets, depending on the field of activity.

Shank selection

The shank is the part that is attached to the chuck of a drill or other tool. There are three common types of fastening: conical, cylindrical and hex. Good drill bits for metal can have any type of fastening: this only affects the tool that can work with a particular tooling.

Based on this, for hand tool it is advisable to choose drills with hex shanks. It is important to remember that you cannot replace one type with another, so the equipment used has the final say. Compatibility of equipment with equipment guarantees maximum efficiency work.

Alloy composition and marking

The cutting part of the tool can only drill through the workpiece or work surface if it is significantly stronger than it. To make it easier to determine which products are made of what, special marking of drills for metal is performed. In addition, many types of spraying and alloys can be immediately recognized by color.

How drills for metal are marked:

The label does not indicate carbon, since it is always present in the original raw materials. The same is true for chromium, although its content can reach up to 4%. Domestic marking is even simpler: next to each letter denoting a metal, there is a number indicating its percentage in the alloy. For example, the designation R7M6K6 indicates 7, 6 and 6% content of tungsten, molybdenum and cobalt, respectively. The letter F may still be found - vanadium, but the cobalt version and alloys with molybdenum and tungsten are more common.

Drills for metal: dimensions, table (DIN marking data - an imported designation for high-strength steel, like HSS).

Color decoding

All the options laid out on the shelves in the store can be divided into four categories by color. Each color says a lot about the quality of the equipment and its expected characteristics.

The choice should be approached from the point of view of practicality. If the store has inexpensive black options, then they will do a great job with everyday tasks and one-time jobs. It makes sense to spend money on high-quality products of golden hues if there is a lot of work and tens or hundreds of holes in the metal.

Popular manufacturers

There are a number of manufacturers whose products you can trust. There are few of them, and most of the companies are quite well-known and well-known.

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

Eat 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:

tree;
ceramics;
polymeric materials;
concrete;
brick.

Structural features must be taken into account material characteristics, which will be processed. If we are talking about metal drills, then 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

Twist drills 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 a stepped and smooth working surface and are used to create holes of small thickness. They are able to provide easy centering of the hole at the beginning of work. Their key advantage- This 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 a large hole in a metal product, 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 manufacturing, 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 accurate 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 the performance of the product.

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 on the materials with which you can work with 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.
During sharpening, press the tool firmly against the grinding wheel, starting 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, the entire 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.

Modern drills and drills allow you to make holes of the desired diameter in almost any metal or less durable material. Types of drills on the shelves of the store are full of not only different markings, but also different quality. Let's figure out how not to miscalculate with the purchase of a drill.

1 Types of drills and their purpose - we conquer metal!

The classification of drills is quite complicated and takes into account many factors: purpose, performance, shape. If we divide them into two original groups, we get drilling tool for metal and drills for wood or other soft materials. Types of drills for metal are distinguished by the presence of two longitudinal grooves that divert chips to the side, as well as a special sharpening angle. However, core and cone drills for metal fall out of this row.

Core products are used for drilling large holes and working with multilayer materials, while they do not really depend on the power of the tool - the structure of the tool allows you to work even with conventional drills, since the cutting forces are relatively small. When choosing crown products, you should pay attention to the shank - it must be powerful and durable in order to prevent slippage in the chuck. Vibrations, overheating - these two factors affect the wear of the tool, getting rid of them, you will significantly extend its life.

Cone drills confirm their name with their shape - it allows you to drill holes of arbitrary diameters, depending on the needs of the master. The operator only needs to mark the diameter of the circle and accurately determine the center of the drill. Conical products with even walls require constant control over the drilling process, while stepped products facilitate work where it is necessary to drill holes of a certain diameter, which corresponds to one or another step.

2 Drills for wood - a set for all needs

Ordinary twist drills with one flute for removal of shaving are intended for works on a tree. Products are presented in a very impressive range of diameters - from 3 mm to more than 50! If this diameter was also insufficient, ring products will come to your rescue, they are also called crowns - not to be confused with core drills for metal! Rings look like rings with teeth, with a center drill.

The disadvantage of such products is that deep holes don't do that - conventional tools able to master a depth of up to 20 mm, professional - almost 70 mm. The same drills are also used when working with other soft materials, such as plastic. How thinner tool, so they should be shorter - the laws of physics cannot be canceled, a thin and long drill will break even with a slight pressure. Thicker products can reach a length of more than half a meter - this is just in case when you need to make a very deep hole.

Please note that deep hole drills will weigh a considerable 2 or even 3 kilograms. For an ordinary household drill, even short-term work will seem like a serious test, however, it is not a fact that such a drill will be able to turn the tool even on Idling. Fountain drill bits for wood are a compromise between length and weight. Drilling occurs due to the thickening of the rod in the form of a pen. The length of the rod is not particularly limited. For this advantage, one has to endure a drawback - the lack of chip removal.

For blind holes (not fully drilled), Forstner drills are ideal. They allow you to make a hole with a perfectly flat bottom. The diameter of the resulting holes can reach 50 mm, and the length of the products usually ranges from 10-15 cm, although there are special extensions.

All drilling products have the same laws correct use- how larger diameter, the fewer revolutions should be set on the drill, the harder the material, the fewer revolutions, the longer drill, the less you should click on it.

3 Marking drills: deciphering the designations

The marking of drills for metal and wood is primarily affected by their diameter. Thin products are produced without any marking at all - the diameter and steel grade are indicated on tools from 3 mm and above. The thicker the drill, the more information should be indicated on it: accuracy class, manufacturer ...

The letters and numbers that are printed on the product are easy to decipher. Traditionally, the marking of products manufactured by domestic factories begins with the letter P - this is how high-speed steel is designated. The number that follows indicates the percentage of tungsten. The following designations indicate mass fractions of other elements. Cobalt is denoted by the letter K, molybdenum by the letter M. The more such elements in the composition, the better the product withstands thermal and mechanical loads.

Traditionally, the percentage value of carbon and chromium is not marked, since in the first case the content of the element is always proportional to the content of vanadium, and in the second case the percentage is always the same - 4%. If vanadium in the composition of steel is more than 3%, then the letters F and a number indicating the amount will appear on the drill.

For imported products, a completely different marking is used - DIN and HSS. DIN drills are multi-purpose tools suitable for both ordinary work and for deep drilling. They work best on metals that form medium to long chips. Products may have different coverage which is easy to recognize by its colors.

HSS drills are distinguished by the letters that come after the abbreviation. So, the letter G indicates that you have a tool that can easily cope with carbon and alloy steels, cast iron, aluminum and copper alloys. E - these are drills that, in addition to alloy and carbon steel, will drill acid-resistant and stainless steel.

For titanium alloy, which is known for its strength, HSS-G TiN and HSS-G TiAlN are suitable. Of course, all of the above metals are also tough for them. Choose tools from trusted manufacturers - good drills are made in Germany, France, the Baltic countries, and there are many worthy ones among domestic manufacturers. Products from China traditionally lose in quality, although they are more affordable.

4 What will tell the color of the metal - choose a set!

The color of a product can tell a lot about its capabilities, no matter what kind of drill is in front of us - for wood or for harder materials. For example, grey colour inherent in the simplest drills without any processing - steel itself has this color. The black color of the surface of the product indicates that the drill finishing exposed to superheated steam. Such tools have more long term operation.

The yellow tint indicates the metal tempering procedure. This procedure relieves internal stress, which acquires excessive fragility. Thus, manufacturers are trying to reach the golden mean - red-hot products have a high strength, but at the same time they are quite fragile. But if you reduce the internal stress by slowly and for a long time heating the metal, the instrument will become somewhat softer, but retain a high degree of strength.

Bright golden color stands for the best products that can handle the toughest complex work. Gold drill makes a layer of titanium nitride, which significantly reduces friction and increases strength. Of course, these tools are not cheap.

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

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

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

What you need to know about metal drills

There are a lot of drills for metal, in addition to looking at 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;
work surface. Its role is that during the operation of the main part, chips appear, which are removed by the working surface;

Expert opinion

Sergey Yurievich

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The end, also called the tail, it is attached to the drill chuck, the movement begins with it.

Drills for metal have many different shapes, each of which is used for a specific type of work.

Depending on the form, there are such types:

The most common type known to all - spiral. In fact, this is a rod, of a cylindrical shape, and on the sides there are one or two spiral grooves (actually because of them, the chips are removed). In turn, twist drills have their own subspecies:

increased accuracy, masters often choose to make a hole perfectly, up to a millimeter;
classic, those cylindrical shape, which are common among both pros and ordinary users;
narrow application, its spiral groove is wrapped to the left, not to the right. Use it in cases where you need to drill something.

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

flat drill. As the name implies, the working surface of this type is flat. The main disadvantage: because of its plane, the chips are not automatically removed, you have to remove them manually. In addition, this drill will not make large holes. But despite the huge disadvantages, they are in demand, as they are very cheap, insensitive to distortions during drilling.

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

The following types differ in that they were created specifically for hard metal, while the previous ones for metals with high density will not work - they will break.

cobalt. Can be confused with spiral, as it also has a spiral shape, but unlike it does not have a cylindrical base. In addition, this species, thanks to cobalt, has high strength. But they are also expensive, so not everyone can afford them, before you take it, evaluate the difficulty of the work.
Carbide. Due to the presence of a hard-alloy plate on the cutting part, due to this it can make holes in fairly dense metals.

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

Rare, but still present bright gold drills. This color indicates the presence in the alloy of the hardest metal on the planet - titanium. Which by itself implies the quality of the part and its strength and value.
light gold the color indicates that the product has received a special thermal preparation. Not as durable and expensive as bright gold, but its price is quite high, not everyone can afford it.
Drill black color treated 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 you need to drill, what diameter of the hole), you can already 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, outbuildings, terraces and verandas.

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

The manufacturer can also play a role, the drills can be identical, but from different companies, in which case choose the manufacturer you know or have dealt with.
To determine the working diameter, look at the marking, since it is not put on products up to two millimeters at all, from 2 to 3 mm only a company sign is put on, 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, therefore it makes no sense to choose, search on the forum which one is better, it all depends on only two things: the task you need to complete and the size of your purchase budget.