A tool for sharpening drills should be in the arsenal of any home master. Fixture for the correct angle of sharpening the drill Sharpening of small drills

It is impossible to perform high-quality metal processing (including drilling a hole in a metal part) without using a tool whose mechanical characteristics and geometric parameters 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 that wears out (which is natural) during operation.

Sharpening a drill for metal with a special tool greatly simplifies the task.

Drills designed 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 operated very long time completely retaining its original characteristics. The situation is quite different with drills, with the help of which holes are made in metal parts. It is necessary to monitor the condition of such drills constantly and immediately take action if their working part has undergone wear.

The fact that the drill for metal needs to be sharpened is evidenced by whole line signs:

• creak and rumble emitted by a worn instrument;
• intense heating of the drill during its use;
• poor quality of the created holes.

Working with a worn drill is not only inefficient, but also unsafe. At any moment, such a drill, on the working part of which there are significant loads, may break, and its separate fragments flying in all directions at high speed can cause serious injury.

Drill sharpening parameters

Both in production and at home, metal drills can be sharpened on emery machines equipped with a grinding wheel of appropriate hardness. It is best to use serial 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 accessories for sharpening drills used with it in the kit, largely determine the quality of such a procedure.

The most important parameters to consider in order to properly sharpen a drill for metal with your own hands are:

1. the angle at which the back of the tool is located to the drilling plane;
2. sharpening angle of the front surface of the cutting part;
3. the length of the transverse jumper on the cutting part;
4. apex angle cutting tool;
5. cutting edge length.

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

It should be borne in mind: if the sharpening of the drill for metal is performed 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 drill for metal yourself, you must first determine what tasks it will be used for. In production conditions, for sharpening drills, as a rule, special devices are 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 of high quality.

The minimum set for sharpening drills for metal should include:

• emery machine;
• grinding wheels of various hardness, selected depending on the material of manufacture of the drill to be sharpened;
• a container for the coolant and the liquid itself, which can be used as ordinary water (or engine 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 of the drill and the base of its cutting edge (such an angle, measured in the main cutting plane, is called the front);
• back angle, which is measured in the same way as the front, but along the back plane of the drill;
• tool nose angle, measured between two cutting edges.

For sharpening drills for metal, according to all the rules, you must follow following values the above parameters:

• rake angle of the cutting part - 20°;
• rear angle - 10°;
• apex angle - 118°.

If you need to sharpen a drill for metal in production or at home, you must strictly observe safety precautions. This process is accompanied by the formation a large number 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 the hands.

An emery machine equipped with a grinding wheel is a universal device that allows you to sharpen a drill bit for metal even at home. Using such a device, the technological operation should begin with the processing of the back surface of the tool. The drill to be sharpened is held in relation to the grinding wheel so that its cutting part is parallel to the surface of the circle. Sharpening performed according to this technique is optimally suited for metal drills with a diameter not exceeding 10 mm.

In order to sharpen drills with a diameter greater than 16 mm (including those equipped with carbide inserts), it is best to use an emery machine with a special tool. The use of the latter allows not only to control the angle of sharpening drills of a significant diameter, but also to perform such a process with maximum safety.

Grinding machines equipped with additional devices 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 characterized by a small amount of subdot.

The main task that devices solve that allow you to qualitatively sharpen a drill for metal on a grinding machine 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 engine that rotates the grinding wheel, as well as the rotary column, on which the machined tool is fixed, are installed on it. The use of such a column allows you to sharpen drills in almost any spatial position, placing their cutting part in relation to the surface of the grinding wheel at the required angles.

Benefits of using special fixtures

The big advantage of using grinding machines equipped with special devices is that the movement of the machined tool on them is provided by a drive connected to an electric motor. The design scheme of such a drive includes a bearing assembly and a shaft. At the end of the latter, a drill is fixed, which must 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 fixture, 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 dimensions are 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, you can recommend more compact devices. One of these devices is a nozzle machine. It is mounted on a conventional spindle electric drill, from which its main working element, the grinding wheel, is set in rotation. One end of such a device is equipped with a special coupling that connects the device to the rotating spindle of an electric drill, and the other end is equipped with a lid with holes of different diameters into which the working parts of the 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. At the same time, you don’t even have to show such a process on video or live, everything is clear and without a 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 grinding wheel. A tool sharpened with such a simple device has all the required geometric parameters.

It would seem that you can sharpen a drill with the help of any device that can set the grinding wheel in rotation. Meanwhile, without the use of devices for fixing the tool during the sharpening process, it is impossible to perform such a procedure with high quality. In addition, you can get seriously injured. You can turn to such a simple sharpening method only if you need to sharpen small-diameter drills that are easy to hold in your hands during processing.

With manual sharpening, a corner fixed on a support will help to maintain the desired parameters.

The modern market is saturated with many types of different equipment designed for sharpening drilling tool. When using it, you do not need to have special skills and training. For example, such devices include industrial devices riss 8100v, which have a high cost. To save money, you can make a tool for sharpening a drill for metal with your own hands.

The specifics of the devices

IN household electric drills and screwdrivers are often used for drilling various materials from wood, concrete, metal and ceramics. Many users of such equipment have repeatedly encountered a problem that causes blunting of the working part of the drilling tool during operation.

While working with metal, intense heating of the cutting part of the drill may occur, which exposes it to rapid wear and further unsuitability for use. To avoid this, it is necessary to periodically check the geometrical norms of the cutting part and, if possible, grind it to the required parameters. For drilling in metals, as a rule, they are used twist drills. An additional check of the tool before performing work extends its service life.

When working with wood, the cutting part is practically not amenable to wear, and drills for concrete are equipped with solid victorious plates that do not need sharpening and are used until they are completely worn out.

Drill sharpening tools

How on industrial device, and on a do-it-yourself drill sharpener, it is recommended to use a specialized template necessary to meet the requirements for the tool. Using a template makes it possible to set the required angle of the cutting part of the drill, which ensures high accuracy when working. During the drilling work it is necessary to individually select the angle of sharpening the tool, depending on the materials used.

When working with metals, reference data can be used to provide information on the required standards when setting the sharpening angle. Sharpening angle parameters for metal drills:

• Steel, cast iron and hard bronze - 116-118;
• Brass, soft bronze - from 120 to 130;
• Copper - 125;
• Aluminum - 140.

IN a simple fixture for sharpening drills, you can use a sleeve with an inner diameter, which must match the cross section of the drill and be fixed on a rigid base at the required angle. The sleeve is selected with high precision- so that its inner diameter coincides with the cross section of the tool being sharpened. It is categorically impossible to allow weak fixation: this sharply reduces the quality of sharpening.

Can be used wooden block, in which holes of different diameters must be drilled, which will make the fixture universal.

An important node is the handpiece, which performs the following functions:

• ensures the correct fixation of the processed object and its movement relative to the grinding wheel;
• is an excellent emphasis during the performance of sharpening work.

Drawings for sharpening drills can be of great help in assembling it. They can be found in various sources of information. By studying the principle of operation of such structures, you can develop your own version, which may differ from the basic one in its individual characteristics.

When working with sharpening devices the following rules must be followed:

• The tool being processed during the work must be firmly fixed, which prevents it from turning around its axis;
• At the end of the grinding work, it is necessary to allow the drill to cool, and then measure its angles using a template. The working surfaces of the cutting parts should not differ from each other.

Even with correctly selected angles and the coincidence of their symmetry, strong runout may occur due to the difference in the length of the cutting edges, which is fraught with breakage of the drill. With asymmetry of the cutting parts, the drilling process slows down and the cutting part of the tool overheats. This makes the hole broken and enlarged in diameter.

Screwdriver tool

For sharpening drills, you can use traditional devices: a sharpener, an electric drill or a screwdriver, with the addition of additional improvements to them.

On sale there is a ready-made industrial fixture for a screwdriver and an electric drill, which is used as a mini sharpener and allows sharpening at different angles.

To sharpen the cutting part of the tool on a homemade fixture, a number of conditions must be met:

For sharpening drills and drills, emery wheels are used. The most common in living conditions is a white electrocorundum circle designed for sharpening shovels, axes, knives, choppers and other household equipment.

For concrete carbide pobedit drills, 64C marking abrasive wheels are used. The grit size of the grinding wheel is recommended to use grade 25H. When sharpening Rapid, use a disc brand from 8H to 16H. When working with silicon carbide emery working surface drill, heated up to high temperatures Therefore, it is recommended to cool the metal with water and soda.

It is quite simple to make a device for sharpening drills with your own hands, the conditions for success will be knowledge of the rules for sharpening a cutting tool, as well as the ability to work hand tool and technical savvy.

The main rules that ensure high-quality sharpening are:

• in one pass, it is necessary to remove an insignificant layer of metal;
• in the process of performing work, the drill is repeatedly cooled in an aqueous or water-soda solution;
• rotational speed emery wheel should be the minimum possible;
• the drill, during sharpening, should not overheat;
• in the process of performing work, the drill is directed against the movement abrasive wheel.

The volume and nature of the work performed depend on the type of wear of the cutting tool. Depreciation can be classified by:

• back surface;
• jumpers;
• corners;
• chamfer;
• front surface.

Depending on the type of sharpening of the drill, it specifications, as well as destinations, the following types of processing are recommended, such as:

How to make a machine with your own hands

For sharpening twist drills, any grinder(unit) powered by electrical network 380/220 Volt, equipped with an emery wheel and equipped with a special device that ensures the fixation of the sharpened drill at a certain angle to the axis of rotation of the abrasive element of the device.

The main requirements for special devices that ensure high-quality performance of work:

1. The axis of the fixture must coincide with the axis of rotation of the abrasive wheel. It can be with it in the same horizontal plane or be slightly higher than it.
2. Equipment and fixtures used must be securely fastened.
3. The design of the fixture should make it possible to sharpen the drill under different angles, depending on the needs of the user.

For the manufacture of one of the variants of such devices you will need:

• Manual metalwork tool, angle grinder ("Bulgarian"), welding machine.
• Sheet steel with a thickness of 3.0 - 4.0 mm, as well as a small diameter steel tube available.

Work on the manufacture of the machine is carried out in the following sequence:

• The used grinder (No. 5 in the diagram) is firmly fixed on the selected surface.
• A platform is made from strip steel (No. 1 in the diagram), on which the drill will be fixed (No. 3 in the diagram).
• The shape of the site can be arbitrary, the only condition is that a groove is made at the location of the drill by means of a “grinder”.
• Holes are drilled on the site (No. 6 in the diagram), which serve to fix the mounting plate (No. 2 in the diagram), as well as holes that connect the fixture to the grinding machine (not indicated in the diagram).
• The shape and size of the mounting plate can be arbitrary.
• An attachment point to the base of the grinding unit is made from a metal tube and strip steel. The presence of the tube allows you to move the device in vertical plane- it becomes possible to change the angle of sharpening the drill.
• The attachment point of the sharpening device to the body of the grinding machine depends on the type and design of the emery wheel protection unit (No. 4 in the diagram), as well as the presence of a stop (platform) of a particular emery unit.
• If desired, the mount can be equipped additional elements, providing oscillatory movement of the device in the horizontal plane, which will ensure the required articulation in the process of performing work.
• After all the elements of the fixture are assembled, it is attached to the stop (casing) of the grinding machine and the performance of the manufactured fixture is checked.

Various emery wheels can be used to sharpen screw drills, but in light of the fact that this consumable(tool) is made of durable steel, then the abrasive elements must comply with this.

Basic requirements for emery wheels:

• Electrocorundum brand - 24A, 25A, 91A and 92A.
• Grain size - 25-40.
• Hardness - M3-CM2

The device for sharpening drills can also be made in a different version than the proposed version - both simpler and complex design. The type of such a device is determined by its need and the user's ability to make equipment with his own hands.

If you are constantly dealing with sharpening hard workpieces, then the surface of the drill will become unusable very quickly. It will become dull, get very hot and eventually lose its former strength. All this is a consequence of the "letting go" of the metal. That is why such a tool needs periodic sharpening using special devices.

How to do homemade devices for sharpening drills, what templates exist for this and what needs to be prepared for work, you will learn from our article.

Features of sharpening drills

Drills are inexpensive devices, especially if we talk about those that are widely used for domestic needs. However, if possible, then after blunting it is better to sharpen the tools than to buy new ones.

There are factory-made sharpening devices, but you will spend a lot on buying them, and this will not make up for the savings if you refuse to purchase new tools. That is why many masters collect machine tools for sharpening by hand.

It is worth noting that blunting applies to metal drills, since wood tools are practically not affected, except when used at high speeds with a resinous workpiece. Also not subject to sharpening Pobedite tips for stone or concrete.

But many drills for metal are sharpened through all accessories with your own hands, but the accuracy of such work is far from always ideal, so it is advisable to use at least a minimum of mechanics.

How to make a do-it-yourself drill sharpener: a tutorial video

To make such a device yourself, you will need a control tool (template). No matter how the drill is sharpened, the accuracy is checked by a special template.

Simple drills for ferrous metal have an edge angle of 115 to 120 degrees. If the metal is different, then the sharpening angles will also be different:

You can prepare right away multiple templates depending on the listed values ​​​​and, in accordance with them, do sharpening with your own hands. The same drill can be used for different types blanks, you just need to change the corners of the top of the workplace.

A simple but very convenient dragging device is bushings different size that are attached to the base. You can make them yourself, based on special drawings. Remember that the tool in the sleeve should not dangle, and the quality of drilling may deteriorate even if the error is only one degree.

You can make a large clip based on aluminum or copper tubes depending on the typical parameters of the drills, or take a bar of soft material and make many holes in it. In the grinder, it is very important to put a convenient handrest, thanks to which it will be possible to right angle move the sharpener and hold the stop.

The listed sharpening devices have been manufactured for many decades in a row and are still in demand. For Assembly grinding machine with your own hands, you can take an oak bar instead of a corner.

The simplest sharpening machine can be assembled by simply placing a workbench or table opposite the side of the emery. Even such a simple device provides high quality and accuracy of work.

Features of sharpening on a simple device

On the Internet you can find finished drawings devices for sharpening drills, or sketch them yourself, but for this you should understand the principle of working with a drill.

During work Absolutely forbidden allow the drill to move around its axis. If it turns at least a millimeter, it will be damaged, and you will have to grind a small distance for re-processing.

After finishing work, the drill should cool down, also measure with templates. The edges must be perfectly symmetrical down to tenths of a millimeter. This is especially important if the drill has a minimum diameter.

Sharpening may be accompanied by such errors:

As from improvised means with your own hands assemble a grinder for twist drills for metal?

For the basis of the device, you can take any grinding machine that is able to work properly, there is no axis beating in it, and it keeps the speed under load.

The task looks like this:

• the handist must strictly stand horizontally on the same axis with the rotation of the emery;
• the design must be safe, reliable and durable;
• it should be possible to sharpen both manually and semiautomatically;
• the shape of the handpiece should facilitate the free lowering of the drill shank to the desired angle.

Specific parts for the manufacture of this device are not required, almost everyone has everything you need home master. Workpieces are processed grinder, welding or grindstone.

For the semi-automatic mode, a rocking stop is assumed, so you need to make a loop connection. Pick the right one for lack of backlash bolt, bracket and tube holes.

The platform must move vertical axis so that you can change the angle of sharpening the drill. This axis can be fixed, and the hand rest should swing, while leaning on the horizontal axis, which provides the desired articulation when sharpening.

Base plate made of metal 4 mm thick, and the main parts of the structure must have a thickness of 3 mm, respectively. This ensures its high strength. The handpiece with the body of the emery is rigidly connected. Attach it to protective cover it is impossible, therefore, use the metal "cheek" to screw the bracket.

Then we fasten the guide plate for drills with a thickness of 5 mm to the base plate. In it, to fix the drill during processing, it is sawn triangular groove.

The design has an angle of rotation of 90 degrees, which allows you to provide z atochka different methods . Starting from the Leontief method and ending with pressing at a certain angle and creating acute angle edges due to the curvature of the emery.

The drill during processing will not only stand firmly in the groove, it can also be fed along the groove to the abrasive, and the sharpening angle will not deviate. Due to the partial excess of the plane of the base plate above the axis of movement of the disk, it is possible to achieve desired shape sharpening the nape of the edge.

Before performing work, the drill should press on the plate and set the cutting edge parallel to it. The adjustment is over and you can bring the tool to the emery. Sharpening must be done slowly and carefully, carefully monitor the angle.

Thanks to this homemade tool, high sharpening precision and almost no template is needed. True, it will take time to install the machine and adjust the angle, but then you sharpen drill bits quickly in the right amount.

But if you need to sharpen a drill equipped with a carbide nozzle, then you can attach a swinging plate to a fixed angle. To do this, put several washers under the axle nut.

Using an emery wheel in a homemade sharpening tool

For universal grinding work, white circles based on electrocorundum are mainly used. They are used for sharpening shovels, axes, knives and metal blanks.

In order to process carbide drills or high-speed metals, it is necessary to take abrasive green wheels based on silicon carbide marked 64C. But for domestic needs, the grain size of the circle is enough for 25N.

Sharpening drills requires a finer fraction in the area from 8N ​​to 16N. Remember that silicon carbide emery gets very hot during operation, so the drill cannot be kept in contact with such an abrasive for a long time. Let the metal cool down after 2-3 passes and chill it in soda water.

Edge quality depends on direction abrasive rotation. Its working surface must run into the cut (go from top to bottom).

Peripheral emery surface during processing must be even. It can be edited with a nozzle based on CBN. If the disc has a small diameter, it is allowed to use pliers, in which the elbor cutter will be held.

So, we looked at how at home you can assemble and use devices of varying complexity in order to sharpen drills and more. Choose suitable option you can according to your household needs.

Drills for metal are always hardened, but products can become dull over time. Naturally, this is not a reason to throw them out. If desired, you can sharpen the drill with your own hands, using professional equipment or homemade devices.

The main types of sharpening

Experienced craftsmen know that sharpening a drill for metal can be different. depending on diameter and application.

• Single plane sharpening is designed for drills with a maximum diameter of 3 mm. In the process of doing the work, it is possible to “chunk” the edge, so you need to be very careful. To properly sharpen the product, it should be applied to the circle and moved parallel to the surface.
• The tapered procedure is for larger metal cutting tools. In this case, the tool must be held with both hands, making consistent sharpening.
• Finishing is performed after the end of sharpening. Thanks to this procedure, it is possible to grind the cutting edge and eliminate even the smallest notches.

To sharpen the drill with your own hands correctly, you must use the appropriate machines. Similar devices are divided into 2 groups.

If you are interested in the question of how to sharpen a drill for metal, then be sure to purchase the appropriate machine. For home use, an inexpensive model with medium power is suitable. It will allow you to sharpen small drills for metal.

Naturally, when buying pay attention to the noise level, as well as the design of the model. The best option will become a simple machine, because to choose for it the right details it will be easy.

It is necessary to buy such devices only in specialized places, since the kit provides for the presence of a technical passport. Moreover, you will be given a warranty card.

Use of machines at home

As mentioned earlier, at home it is advisable to use household machines. With their help, it is possible to sharpen various types of drills. It is important to remember that for some varieties you will have to buy the appropriate circles.

To sharpen the drill yourself, you should give preference to a machine equipped with a universal chuck. It allows you to clamp elements of various diameters.

The kit often comes with:

• keys;
• collets;
• spare parts;
• lamp for the working area.

The equipment from Drill Doctor and GS is the most popular. Similar products are designed for sharpening drills with a diameter of 2–13 mm and 14–34 mm. Unfortunately, this equipment does not allow you to sharpen drills that are too thin. For this purpose, you will have to purchase a special machine.

All equipment designed for sharpening drills at home, has a number of advantages:

• the ability to work from the mains;
• high performance;
• ease of use;
• functionality;
• sharpening accuracy;
• affordable price;
• compact dimensions;
• light weight;
• convenient control system, thanks to which you can adjust the intensity of sharpening and its speed.

Homemade sharpeners

If you do not have the appropriate machine, then you can sharpen using other devices. It is about an electric drill or homemade equipment, created according to the drawing. It is best to give preference to the second option, otherwise you can ruin a lot of drills before you master the correct sharpening.

You can even create a suitable fixture with your own hands from wood. So, on a horizontal surface, a beam with holes corresponding to drill diameter. The mentioned holes are made at a slight inclination to obtain the required sharpening angle.

Some masters prefer an electric drill equipped with the appropriate nozzles. Naturally, a small range of similar items, which complicates the sharpening with your own hands. As a rule, a stone and a leash are included with the nozzles. If you plan to sharpen drills using a specific drill, the leash should be shortened immediately.

If you wish, you can independently make a similar nozzle for a drill, guided by the recommendations given in the corresponding video. Such devices must be equipped with fasteners for fixing the drill.

Features of the sharpening process

If you first decided to sharpen a part with your own hands, do the work in a strict sequence.

1. First of all, the back surface is processed. So, the drill is pressed tightly and constantly monitored so that the sharpening angle remains the same. As a result of processing, the tip of the drill will resemble a regular cone.
2. Next comes the turn of the cutting part.
3. The last stage involves finishing the back surface. In this case, it is necessary to make sure that the size of the jumper is no more than 0.4 mm. Naturally, for a large drill for metal, this parameter should be slightly larger.

If something doesn't work out right the first time, don't despair. It is best to start practicing with tools that are unlikely to be needed. The main thing is to learn how to press and maintain the angle correctly. In this case, it is necessary to take into account the fact that the side parts of the drill, and not the tip, are responsible for drilling. Accordingly, the edges must be sharpened.

It is important to remember that in the process of sharpening small particles are formed. Because of the heat, they scatter in the form of sparks. It is for this reason that safety precautions must be followed. We are talking about the use of goggles and gloves. Also, when sharpening, make sure that the drill is securely fixed. Otherwise, it may accidentally slip out of your hands.

If you decide to use the appropriate machine for sharpening, be sure to prepare workplace. In particular, it is about good lighting. Also need wear protective gloves and goggles.

To properly sharpen the drill with your own hands, you need use a suitable device. It can be a household or industrial machine, as well as an electric drill with a special nozzle. If you have not tried to sharpen a drill before, first check out the corresponding video.