How to sharpen a drill correctly at home. Homemade tools for sharpening drills. Drill initial position

Tools become unusable over time: they become dull, break and crack. Not all consequences of use can be eliminated, which is why you have to purchase new devices, but some can still be restored and given a second life. This is especially true for drills, which during use can not only break, but also become dull.

Types of drills for metal

Today you can make a hole in non-ferrous metals, steel, cast iron without using special equipment. For such purposes, you only need a high-quality drill and good drill bits.

This type of product is produced different forms. For example, cutting tool in the form of a spiral, which is formed by several longitudinal grooves that remove chips. Such a device is usually called a spiral device.

Methods for sharpening drills for metal

Single-plane processing at home. This option is used when it is necessary to sharpen products no more than 3 mm.

The disadvantage of this sharpening is that the edge may chip during operation. This technique requires special care. Its essence is that the drill is applied to the circle and moves parallel to the working surface.

Sleeve or two-plane sharpening

This option is widely used by craftsmen to sharpen products. In this case, special bushings are used. First of all, you need to take left hand the drill by the working surface, then it should be brought to the intake cone, holding the device by the tail with your right hand.

The cutting edge of the product will be press against the butt grinding wheel and eventually the drill will rotate around its own axis with the help of your right hand. In this way the back surface of the tool will be sharpened.

The main thing is to maintain the correct angle , formed between the end of the grinding stone and its inclination. This is why special bushings are used to maintain the angle drill sharpening but for metal.

Conical sharpening

When you start sharpening twist drills with your own hands, first they process the back part, and then the cutting part. The work is carried out as follows:

Using attachments for sharpening metal drills

This convenient method involves the use of special devices for sharpening products. The advantages of this method include ease of use and versatility. This device has a cylindrical shape.

It contains, on the one hand, a connecting unit, with the help of which the attachment is put on the drill spindle, and on the other, there are recesses for installing drills of a certain width. To process it, you need to insert the product into the hole, after which all that remains is to set the device in motion with the drill motor and maintain the sharpening angle.

Finishing after sharpening the drill

Without finishing the product, it will not be possible to eliminate roughness and achieve smooth surface. In addition, drills subjected to finishing, gain wear resistance.

It is advisable to perform it with grinding wheels made made of green silicon carbide. When making adjustments, it is important to maintain the symmetry of the axes. To avoid mistakes, it is better to check correct sharpening of the drill angle with a template, which you can make yourself from the following materials:

1. Aluminum.
2. Copper.
3. Steel.

Sheets of them should have a thickness of approximately 1 mm. Steel products are the most durable. Using the template, you can find out the length of the edges for cutting, as well as the angle between the jumper and the cutting part. It should be done before starting to use a new tool in order to transfer the required angles from the last one.

The easiest way to determine the correctness of the point is - carry out test drilling. When the cutting feathers are sharpened unevenly, in the less loaded part, chips will come out of the hole in small quantities. Sometimes it flies out through only one recess. Moreover, the diameter of the excavation made may exceed the thickness of the drill.

After sharpening a drill for metal, you need to pay attention to its symmetry. To make sure the work was done correctly, you will need a regular drill. Using this tool, they drill into plastic, and then check which side will produce more chips. It is this facet that will need to be refined.

Rules for storing new and sharpened products

When carrying and storing metal drills, you must ensure that they do not rub against each other. Remember that when removing the device from the general box, the cutting working edges will become dull on adjacent products.

Therefore, it is better to make individual bushings or storage holes them in vertical position. On top of that, it is recommended to sign the dimensions so that the search for the drill required size didn't take much time. Of course, it is necessary to control the humidity in the room to avoid corrosion of products.

Spiral products should be processed along the trailing edges. They should work out absolutely identical after work.

Moreover, doing this is not so easy, especially in manual mode, because it is necessary withstand a certain form and angle tool while sharpening.

Before you start sharpening a cutting tool, it is advisable to practice first on non-working products. It is also worth considering the fact that the drilling is performed by the side edges of the device.

Sharpening is carried out to return the cutting part of the product to its factory shape. When working it's worth stick to the basic rule sharpening of tools with tips from various alloys: the harder the material of the drill being processed, the lower the sharpening speed.

Every owner knows what a reliable assistant this power tool is. IN necessary places It drills holes of different diameters with ease. This is only possible thanks to drills. Drills may need sharpening during operation. Some decide to simply replace them by buying new ones. But in most cases, old drills can be brought back to life. In this article we will tell you how to properly sharpen a drill. Let's look at the differences in sharpening drills for wood, metal and concrete.

What you need to sharpen a drill at home

No matter what materials the drill is used for, you must prepare the following tool and material in advance:

• Protective glasses.
• Water container.
• Drill.
• Grinding wheel or sharpening machine.

In most cases, drills up to Ø16 mm are used at home. Therefore, you should not have any particular difficulties when sharpening such drills. The most important thing is to understand the principle of this process.

Sharpening a twist drill

As for wood drills, they need to be sharpened extremely rarely. The same cannot be said about metal drills. Such a drill should always be sharp. How do you know if a drill needs sharpening? When drilling begins, it makes a characteristic creaking sound. A worn drill quickly heats up the product and, accordingly, wears it out even more. As a rule, drills are sharpened at special machines, at home you can use a small grinder with a stone. So, how to properly sharpen a drill for metal? The method and type of sharpening will directly depend on the required shape of the back surface of the drill. For example, it could be:

• Single-plane.
• Two-plane.
• Conical.
• Cylindrical.
• Screw.

In any case, the drill is sharpened along the back edge. Two teeth are sharpened equally. If you decide to do this manually, it will be quite inconvenient. Moreover, it will be extremely difficult to maintain the required shape of the back edge and angle manually.

A single-plane sharpening is characterized as such because the back of the nib has one plane. The rear angle averages 28–30°. When sharpening, the drill must be placed against the circle so that its cutting part runs parallel to the circle. In this case, the drill cannot be rotated or moved. This manual sharpening method has one drawback: the cutting edge of the drill is chipped. But at the same time, for a Ø3 mm drill, this is the easiest method of manual sharpening.

If you want to sharpen a drill larger than Ø3 mm, then the conical method is chosen. Although sharpen by this method difficult, but it is possible. Right hand You should take the drill by the tail, and with your left hand by the working part closer to the intake cone. The drill is pressed against the end of the grinding stone by the cutting edge and the surface of the rear part. With your right hand you need to shake it slightly, thereby forming a conical surface on the edges. Hand movements should be smooth and slow; hands should not be lifted from the stone. To sharpen the second feather, the procedure is repeated.

What is the purpose of such a point? The drill resource increases by reducing the rake angle, and the angle of the cutting edge increases, respectively, all this increases the resistance of the drill to chipping. The width of the cross edge will automatically become smaller. This edge does not drill into the metal, but only scrapes it in the central part. If possible, you can fine-tune the drill. This process refers to the removal of burrs after sharpening. So, the drills will last much longer. For this process, you can use grinding stones made of green silicon carbide on a bakelite bond, hardness M3-SM1, grain size 5–6, stone grade 63C. In addition, you can take a grinding wheel made of CBN LO on a bakelite bond with a grain size of 6–8.

How to sharpen a pobedite drill bit

As a rule, a Pobedite drill bit is used for concrete. It may also need sharpening. During the drilling process, a dull drill bit will become very hot and, accordingly, may make a characteristic squealing sound. If you want to save money on buying a new one, then you can try sharpening the drill yourself. To do this, just prepare:

• Sharpening machine with diamond wheel.
• Coolant.

If the soldering on the cutting part of the drill is 10 mm high, then you can sharpen the Pobedit drill.

One important thing to consider known fact The harder the material, the lower the sharpening speed should be. On a Pobedit drill, you only need to correct the slick edges, so sharpening it will be quick. It is important not to rush during the process, otherwise there is a risk of licking off the excess surface of the drill. It is necessary to sharpen the front surface of the drill. In the case when the soldering has already been ground down to the base of the drill, sharpening will be required. In order for the thickness of the soldering center to be smaller, it is necessary to sharpen the front surface at the same time. After sharpening, both cutting sides must be the same size, otherwise the holes will be uneven and enlarged. During sharpening pobedit drill It is important to maintain an angle of 170°, this is especially necessary if the material is quite hard.

It is not allowed to overheat the drill during sharpening. The carbide plates may peel off and the surface may crack. Therefore, during the process, you should cool the drill in water or oil from time to time.

So, we have looked at the basic principles of sharpening drills for wood, concrete and metal. You can share your comments!

Video

After watching the following videos, you will learn how to sharpen twist drills. This video tutorial covers sharpening technology in detail in four parts.

Processing the back surface of the drill:

Grinding the drill jumper:

Technology for sharpening small-diameter drills, carbide drills and others:

It is impossible to perform high-quality metal processing (including drilling a hole in a metal part) without the use of tools, mechanical characteristics And geometric parameters which correspond to the required values. That is why the question of how to sharpen a metal drill correctly is relevant for home craftsmen who often work with such a tool, which wears out (naturally) during use.

Sharpening a drill for metal using a special device greatly simplifies the task

Drills intended for metal work have to be sharpened much more often than those used for wood processing. When processing such soft material, which is wood, drills practically do not become dull and can be successfully used very long time, fully maintaining its original characteristics. The situation is completely different with drills, which are used to make holes in metal parts. It is necessary to constantly monitor the condition of such drills and take immediate action if their working part is worn out.

The fact that a metal drill needs to be sharpened is indicated by whole line signs:

• creaking and humming noise produced by a worn-out instrument;
• intense heating of the drill during its use;
• low quality created holes.

Working with a worn drill is not only ineffective, but also unsafe. At any moment, such a drill, the working part of which bears significant loads, can break, and its individual fragments scatter into different sides at high speed, can cause serious injury.

Drill sharpening parameters

Both in industrial and at home conditions, metal drills can be sharpened on emery machines equipped with a sharpening wheel of appropriate hardness. It is best to use commercial equipment in such cases. If it is not available, then you can sharpen drills on devices made by yourself. It should be borne in mind that the characteristics of this equipment, as well as the devices for sharpening drills used in conjunction with it, largely determine the quality of such a procedure.

Most important parameters things to consider in order to properly sharpen a metal drill with your own hands are:

1. the angle at which the back of the tool is positioned to the drilling plane;
2. sharpening angle of the front surface of the cutting part;
3. length crossbar on the cutting part;
4. cutting tool tip angle;
5. length of cutting edges.

In order for the drill to be sharpened with high quality, it is necessary to ensure that it is fed into the processing area at the required angle. To solve this problem, use various devices, which are equipped with sharpening machines.

It should be kept in mind: if sharpening a drill for metal is done incorrectly, this can lead not only to a poor-quality result, but also to breakage of the tool.

What is needed for the procedure

To sharpen a metal drill yourself, you must first determine what tasks it will be used to solve. In production conditions, for sharpening drills, special devices are usually used to ensure maximum accuracy and productivity of such a process. When sharpening drills at home, you always have to look for ways to make the result of this process high-quality.

IN minimum set To sharpen metal drills, the following must be included:

• emery machine;
• grinding wheels of varying hardness, selected depending on the material of the drill that needs to be sharpened;
• container for coolant and the liquid itself, which can be ordinary water (or machine oil);
• devices that allow you to maintain the correct sharpening angles.

When sharpening drills with your own hands, you need to pay attention to the following parameters:

• the angle between the plane of the front part of the drill and the base of its cutting edge (this angle, measured in the main cutting plane, is called the front);
• rear angle, which is measured in the same way as the front angle, but along the rear plane of the drill;
• tool tip angle measured between two cutting edges.

To sharpen drills for metal, according to all the rules, you must adhere to the following values ​​of the above parameters:

• front angle of the cutting part – 20°;
• back angle – 10°;
• apex angle – 118°.

If you need to sharpen a metal drill in production or at home, you must strictly follow safety precautions. This process is accompanied by the formation large quantity sparks, from the effects of which it is necessary to protect the organs of vision. In addition, since this procedure is performed with sharply sharpened metal instruments, it should be carried out using gloves to protect your hands.

An emery machine equipped with a grinding wheel is universal device, which allows you to sharpen a drill for metal with high quality even at home. Using such a device, technological operation you should start by processing the back surface of the tool. The drill to be sharpened is held in relation to the grinding wheel in such a way that its cutting part is parallel to the surface of the wheel. Sharpening performed using this method is optimal for metal drills whose diameter does not exceed 10 mm.

To accurately sharpen drills with a diameter greater than 16 mm (including those equipped carbide inserts), it is best to use an emery machine with a special device. The use of the latter allows not only to control the sharpening angle of drills of significant diameter, but also to carry out this process with maximum safety.

Sharpening machines equipped with additional accessories are recommended for use in cases where it is necessary to sharpen drills of the following categories:

• used for drilling blind holes, which is characterized by a decrease in axial cutting force;
• universal, characterized by increased strength;
• used for drilling deep holes and differing in insignificant size of the point.

The main task that devices that allow high-quality sharpening of a drill for metal on a sharpening machine solve is the correct orientation of the cutting part of the tool in relation to the surface. That is why the design of such a device has a special base plate. The machine itself, the motor that rotates the grinding wheel, and the rotary column on which the tool being processed is fixed are installed on it. The use of such a column allows you to sharpen drills in almost any spatial position, positioning their cutting part in relation to the surface of the grinding wheel at the required angles.

Benefits of using special devices

The big advantage of using sharpening machines equipped special devices, is that the movement of the tool being processed on them is ensured by a drive connected to an electric motor. Structural diagram Such a drive includes a bearing assembly and a shaft. At the end of the latter there is a drill that needs to be sharpened.

Before starting the procedure, the tool is fixed on the device at the required sharpening angles. After the metal drill is fixed on the movable column of the device, it itself is brought to the rotating grinding wheel. Thus, all the angles that need to be formed on the back surface of the cutting part are maintained automatically during the sharpening process. Among the main disadvantages of such a machine for sharpening drills, its large size is usually noted.

If you are looking for an answer to the question of how to properly sharpen a drill for metal without performing complex manipulations with the tool being processed, we can recommend more compact devices. One such device is a nozzle machine. It is installed on a conventional spindle electric drill, from which its main working element, the grinding wheel, is driven into rotation. One end of such a device is equipped with a special coupling that connects the device with the rotating spindle of an electric drill, and the other with a cover with holes different diameters, into which the working parts of sharpened metal drills are inserted.

It is very easy to teach someone how to use this device, which allows you to quickly sharpen a drill at home. In this case, you don’t even have to show such a process on video or live, everything is clear without demonstration. To sharpen a drill for metal using such a device, it is enough to insert the tool into a hole of the appropriate diameter until it stops and turn on the electric drill, which will rotate the sharpening wheel. A tool sharpened using such a simple device has all the required geometric parameters.

It would seem that you can sharpen a drill using any device that can rotate a sharpening wheel. Meanwhile, without the use of devices for fixing the tool during the sharpening process, it is impossible to perform such a procedure efficiently. In addition, serious injuries may occur. You can use this simplest sharpening method only if you need to sharpen small-diameter drills that are easy to hold in your hands during processing.

At manual sharpening A corner attached to the support will help you maintain the required parameters.

Reading time ≈ 5 minutes

If you are interested in the question of how to sharpen a metal drill at home, then this article is for you. For those who are closely associated with metal processing, it is extremely important to have good tool. To drill a specific metal part, you will need a drill that is well, and most importantly, correctly sharpened.

Drill – indispensable assistant in metal processing

What's the difficulty?

A drill is a cutting tool, and the cutting edge becomes dull over time. Indicators that a drill needs sharpening are:

• characteristic sounds that a worn instrument makes, including an unpleasant hum and creaking;
• poor quality of the holes made;
• The drill gets very hot during operation.

Peculiarities of chip yield at different sharpenings

Important: using a drill that is not sharpened correctly is, first of all, ineffective and also very dangerous for the master himself. The fact is that the working part of the drill is subject to high loads. Therefore, an incorrectly sharpened drill can simply break, and its particles scatter in all directions with high speed. And this is fraught with serious injuries for the master and damage to the workshop.

Important criteria in sharpening metal drills

In industry, to sharpen a drill for metal, a special emery machine is used, on which a special sharpening wheel with the required hardness is installed. You can sharpen it at home. Of course, mass-produced machines are preferable for use, but homemade options are also perfect for the task at hand. The drill will come in handy to...

Types of sharpening for twist drill for metal

If specialized machine If you don’t have it in stock, you can make a device yourself that will allow you to return the drill to working condition. The performance of such devices will determine how high-quality the result will be.

The most significant criteria, without which it is impossible to carry out proper sharpening yourself, include the following:

• the angle of placement of the rear zone of the tool to the drilling plane;
• jumper length per cutting side, which is located transversely;
• the angle of the tip of the tool that cuts;
• angle of sharpening of the surface in front of the cutting side;
• edge length.

Criteria for correct operation

To fully sharpen a drill for metal, you need to organize the correct supply of the drill to the place where it will be processed. It is important to maintain the working angle here. To achieve this, various devices that are equipped with sharpening machines will help.

We must not forget that if the drill is processed incorrectly, you can not only break the working tool, but also get injured.

Basic tools

To organize in makeshift conditions good sharpening drill, which is used for processing metal parts, you must first decide. It is important to understand why exactly you need it. On industrial enterprises The sharpening process takes place using specialized equipment, which ensures maximum results and speed. But in a home workshop you have to use your ingenuity to achieve a result of similar quality.

How important is it to maintain the correct sharpening angle?

Even the simplest sharpening kit should include:

• emery machine;
• container where the cooling liquid will be located. She could be plain water or machine oil;
• grinding wheels that have different levels of hardness. In the future, it is necessary to choose the level of hardness of the wheel, taking into account the material from which the drill being sharpened is made;
• additional devices that allow you to provide the required sharpening angle for each specific sharpening process.

In order for the technology to be sustained and produce positive results, the following parameters must be observed:

1. The angle of the cutting zone at the front is 20 0 .
2. The rear angle is 10 0.
3. The apex angle is 118 0.

The ratio of angles at the apex based on the type of materials

Regardless of the equipment used and the material of the drill, you need to remember your own safety while working. It should be noted that when sharpening, sheaves of sparks are formed. They may cause burns, so keep them covered. open areas bodies. Special protection should be provided to the eyes. The process also involves working with unusually sharp tools. Therefore, working without protective gloves is prohibited. And the formation of chips at high speed can also damage exposed skin.

The machine with emery on which the grinding wheel is mounted belongs to universal designs. With their help, you can produce high-quality drill sharpening even at home. the main task– choose sandpaper and follow a few simple rules.

When working with such structures, it is first necessary to process the rear zone of the tool. This technology is considered the most rational. The drill being processed must be held so that the part that cuts is strictly parallel to the surface of the sharpening wheel. This technology must be followed to sharpen all types of drills with d less than 10 mm.

Sanding machine in a regular workshop

If necessary, sharpen drills with d above 16 mm. It is more efficient to work on an emery machine with a special device. This technology guarantees control of a constant sharpening angle, ensuring highest security work. This is suitable for both drills large sizes, and for drills that have inserts made of carbide materials. Your sharpened drill will definitely come in handy if necessary.

And even more practical advice You can see how to sharpen a metal drill at home in the video below. The main thing is to work in accordance with the recommendations and observe safety precautions.

1. When should you sharpen a drill?

Wood drill bits can be used very for a long time, without requiring sharpening, which cannot be said about drills for metal or concrete, they become unusable quite quickly. Experienced craftsmen are able to identify dull drills by sight or by contact with the metal of the drill. However, if you are new to construction, it will be quite difficult to determine the sharpness of a drill by instinct, so use these factors to determine that the drill needs to be sharpened:

• a creaking or whistling noise is heard during drilling;
• the tool you are working with heats up very quickly;
• the quality of the resulting hole is very low - there are nicks;
• The chips come out of only one spiral flute.

Please note that if you use a drill with a dull tip, it may break. If it breaks, the flying parts of the drill can cause serious injury. In addition to injuries, the drill can “bite” the material and if you use a powerful tool, it can be torn out of your hands, which often causes serious injuries. Therefore, under no circumstances should you delay sharpening the drill or replacing it.

About. how to choose a screwdriver based on expected construction work, you can read in our

2. Basic parameters of the drill

In order for you to properly sharpen a drill tip, you need to understand the basic elements:

• a cutting part formed by the convergence of the groove surface and the flank surface;
• the front surface, which is located under the cutting edge;
• back surface, located behind the edge;
• a bridge between two rear surfaces.

During the drilling process, it is often the cutting edge, the bridge and the rear surfaces of the drill that suffer the most. Therefore, the drill must be restored by sharpening the rear surfaces. But not everything is so simple: in order for the edge to be sharp again and a clear bridge to form, the sharpening angles must correspond to the values ​​​​indicated in the table:

Provide maximum efficiency work is possible if these values ​​are observed - the cutting edge will always be the first to come into contact with the surface of the workpiece. The length of the cutting edge depends on the apex angle. With a correctly sharpened cutting edge angle, the chips will fit well into the groove and come out. If you make the angle sharper, the width of the cut strip will increase, but the chips will clog the groove. If you make the cut angle too obtuse, the drilling efficiency will decrease.

3. Sharpening the drill on a grinding machine.

Using a regular sharpening machine, you can easily sharpen a drill bit for metal, wood or concrete. Important point— the machine must be equipped with a platform, which is located in front work surface grinding disc. The distance between the platform and the end of the circle should be no more than one millimeter. Stores sell sharpening machines that may not have this platform. If your sharpening machine is not equipped with a platform, but you still want to sharpen a drill, scroll below, where we will tell you how to sharpen a drill with your own hands using a grinder or sandpaper.

Be sure to keep in mind that an angle grinder is a very dangerous tool and you must follow safety precautions when sharpening drills using a grinder.