How to sharpen a wood drill bit. How to sharpen a drill at home. A few words about the repair of drills for concrete

Wood is a material that is easy to process various tools. One of their types can be a drill. You have to use a drill when processing material quite often.

The holes to be drilled can be of different diameters, as well as blind or through.

For a small size, a tool for metal is usually used, but for an enlarged diameter, a specialized drill for wood with a large diameter is used.

There are several types:

There are, but rarely used, drills for cutting cone spikes, cork, etc., etc. Let's consider some of them.

Twisted, or single-stranded

A spiral, or screw, wood drill is available with two types of working tips: conical and special cutters. The basis is a cylindrical rod, the working part of which is formed by helical spiral grooves. Grooves effectively remove chips during operation.

Used to perform deep holes. Holes with this tool are even, smooth and neat.

ballerina

It is an adjustable device with incisors. The gimlet in the center performs pre-drilling, and the cutters cut along the circumference. When setting the desired diameter, the cutters move along the guide at the same distance from the gimlet and are securely fixed.

Due to the design features deep holes cannot be made. Maximum size holes do not exceed 300 millimeters.

Crown

Used for shallow drilling through holes. A disk is used as the basis, in the center of which a spiral gimlet is installed. Saw blades are installed in special places. Usually produced in sets with canvases of different sizes up to 100 mm.

Forstner drill for wood

The Forstner drill is mainly used for furniture production, for drilling holes of exact diameter. It allows you to easily make a blind hole. Blades are available in different diameters working surface: 10, 16, 24, 27, 32, 36, 38, 40, 45, 50 (mm). The price depends on the diameter, the larger it is, the greater the price.

It is a drill consisting of cylindrical shank with two cutting edges and circumferential edge. The cutter is characterized by perfectly even hole edges and a long service life.

Fountain drill

For drilling any kind of wood, quite often, feather drills are used.

The feather drill is designed to make through holes of different diameters. Of course, you can drill with other types of drills, but The advantage of a pen drill is as follows:

• low price;
• good diameter selection step;
• ease of use, no pre-drilling required;
• high performance;
• the possibility of using an extension cord.

The disadvantages include the quality of work and rather rapid wear of the cutting parts, and therefore are usually used for rough operations that do not require surface cleanliness.

What is a drill?

Structurally, the drill is made in the form of a rod. The upper part of the rod is a hexagon designed to be clamped into the drill head. The lower part, the working one, has the form of a blade, in which two cutting blades of a special shape are sharpened on the sides. Thanks to this shape, the blade cuts into the wood, removing chips in a circle. In order for the drill to be stable during operation, a centering tip is made in its very center below the blade.

By their appearance, drills can be one-sided and two-sided. The bevel angle of the cutter, for one-sided is 70-90 degrees, and for double-sided 115-135 degrees.

The drill has a standard length of 150 mm. Using a special extension cord, the depth can be increased up to thirty centimeters.

So, The following parts of the tool can be distinguished:

At points of sale, you can purchase both a set of drill bits for wood and single ones. They are produced different sizes diameter. A number is indicated on the blade indicating the diameter of the hole in millimeters that it can perform, for example, 50. The maximum diameter used is sixty millimeters. No longer produced, as the tool will simply break under such a load. The most popular set consists of diameters: 10, 12, 16, 18, 20, 25 (mm).

The tool is distinguished by color:

• Golden. The material was treated with internal pressure relief.
• Dark. Heated steam treatment was carried out to increase the strength of the material.
• Bright gold. The surface is coated with titanium nitride, which increases the service life of the tool.
• Steel. No additional processing.

Features of use

It is better to use such a drill with a drill that has speed control. They must be set to medium mode, since when working on high speed the chance of drill breakage increases. It should be noted that the rule larger diameter drill, the lower the rotation speed must be set.

During operation, the middle of the drill must be set strictly perpendicular to the workpiece being processed, the pressing force is small. The chips that appear in the created hole, due to the design of the drill, must be periodically removed. If this is not done, it will become impossible to control the drilling process, and the load on the drill and tool will also increase.

I would like to highlight such an interesting tool as an adjustable drill bit. This tool allows you to make holes with a diameter of 22 to 76 mm. Such a device is very convenient to use for non-standard diameters, for example, 23 mm, 52 mm, etc. Work is exclusively carried out at low rotation speeds, with power tools.

How to sharpen a drill bit?

As mentioned above, the disadvantage of a pen tool is the rapid wear of the cutting edges, but at the same time it is not difficult to sharpen them yourself.

Any abrasive material can be used for sharpening. You can sharpen by hand or on a machine. It is best to sharpen the cutters according to the pattern, and try to grind the tip in the center. When sharpening a pen drill for woodworking, you must be very careful not to accidentally damage this tip.

After finishing the sharpening process, it is necessary to perform test drilling and, if necessary, correct the cutting blades or centering.

Summing up, it should be noted: the choice of a tool will primarily depend on the requirements for the quality of work when processing the material, as well as technological conditions. For one-time work, you can also use a cheap tool, while for permanent work it is better to use drills produced by well-known manufacturers Bosch, Makita, DeWalt, Heller. They are made from quality materials which will ensure a clean cut and a longer service life.

The Lewis drill is designed to produce deep holes of small diameter in wood of various species with any degree of moisture. The auger-shaped cutting edge of the drill begins with a sharp tip, with which the preliminary centering of the future hole is performed. And the spiral itself removes chips from working area.

Design

The Lewis drill is included in the main tool kit of a professional carpenter, being light in weight, it does not load the electric drill motor, and allows you to make blind and through holes in hard-to-reach places: corners of beams, places of fastenings wooden parts overlap, etc.

The twist drill consists of the following sections:

1. Shank, which has a hexagonal profile and is designed to fix the drill in a drill chuck or drilling machine.
2. The main working part, which is a spiral tape of constant cross section and a relatively small angle of inclination. For the Lewis helix, it is chosen in such a way as to ensure reliable removal of chips from the drilling zone.
3. Centering, ending with a tip with a conical thread, which allows you to reduce the axial load during the operation. For a tool of relatively low rigidity (and the twist drill is just that), high axial loads become the main cause of breakage.

Due to the complexity of the Lewis drill profile along its length, such equipment is almost never made in a welded version. The material is high-speed steel grades 10R6M5, R6M3 and the like, according to GOST 19265-74.

The features of the Lewis spiral are considered to be its single-thread, which provides the drill with the possibility of spontaneous retraction into the cavity of the resulting hole. At the same time, the direction of the drill is improved, and, as the hole deepens, the edge is trimmed to obtain a smooth generatrix.

How does a Lewis drill work?

At the initial moment of drilling, a conical tip is pressed into the material, which, when rotated, penetrates deep into. Then the main, spiral part of the drill rests on it. Unlike other designs of wood drills, the tool in question at the initial moment has only one working edge, and then drilling occurs with a spiral cutting part. With an increase in the total length of the cutting edge, this contributes to a decrease in the total axial force on the drill, but increases the risk of jamming and "driving" the drill from the center.

The first problem is solved in the following way. Firstly, it is preferable to install the Lewis drill on low-speed, more powerful drills. Secondly, it is not advisable to use such spiral-shaped drills for making holes in hardwoods, since the resulting chips contribute to jamming of the waste in a rather long groove. Usually the number of revolutions is chosen inversely proportional to the diameter of the resulting hole.

To solve the second problem, the twist drill can be used as a reamer, and the preliminary pass, except for particularly deep holes, can be performed using a conventional drill. It is known from operating experience that the direct production of holes using a Lewis drill is advisable for diameters not exceeding 15 ... 30 mm. In other cases, use drill bits, and the spiral one is used only on the last pass, when it is required to increase the smoothness of the side walls.

The moisture content of the wood when using such a drill does not matter, as well as the direction of the wood fibers.

Features of use

Among the advantages of Lewis drills, it should be noted:

1. The smoothness of the increase in the working load as the tool deepens into the material.
2. High quality inner surface holes, since the burrs formed during drilling are completely cut off by the side cutting edge and are immediately removed by the auger generatrix of the drill to the outside.
3. The wide helix ensures reliable chip removal, regardless of the amount of chips.
4. The hexagonal tip on the shank ensures a secure hold of the drill in the chuck.

High quality and productivity, especially noticeable when making holes of considerable depth, do not negate some of the limitations of twist drills:

1. When the Lewis drill is jammed, which is possible in operations with solid wood, its stop occurs almost instantly, and is accompanied by a sharp return. This may result in injury to the worker.
2. Since the cutting forces are high for this type of drilling, the quality of the material is decisive for the durability of the auger drill. Therefore, it is worth purchasing tools from well-known manufacturers that indicate the grade of steel (the grade is usually not indicated on Chinese-made drills).
3. The twist drill has increased brittleness, since during hardening it is usually annealed over the entire section. With relatively low rigidity, this can cause the destruction of the working part.
4. The cost of Lewis drills is higher than conventional drills with the same hole diameters.
5. Low-power drills (less than 1000 W) when starting, the drill of this design may not turn. It is also important that the drill has a reverse function.

How to sharpen a Lewis drill?

With a sharp increase in the load during drilling, as well as a deterioration in the quality of the resulting hole, Lewis drills must be sharpened. It is produced in the following sequence:

• With single-plane sharpening, the back angle of the drill is set to 28 ... 32º with a file, and they try to maintain this value along the entire length of the screw part. Using grinding wheel the drill cannot be moved. This sharpening is used for twist drills of small diameter;
• With conical sharpening, which should be performed for drills with a diameter of more than 6 ... 8 mm, the tool is placed at the side of the grinding tool. Right hand hold the point, and the left - screw part drills, and as close as possible to the cone. Swinging the tool at an angle of approximately 45º and pressing it against the end, they try to recreate the previous value of the taper when moving from the threaded part to the screw;
• If it was not possible to maintain the required parameters, the Lewis drill can be sharpened. To this end, the front angle is reduced, and the width of the cutting belt is increased. True, in this case, the drill cannot be used with the same efficiency for drilling viscous wood with high humidity;
• At the final stage, the drill is finished, which consists in removing all the identified risks and notches, after which the conical thread on the tip is restored.

Work with Lewis drills must be done with some experience, because this design tool is very sensitive to the torques that load the drill.

In the arsenal of any master there is a set of tools that can be useful for solving a wide variety of household repair problems. These include a set of screwdrivers, an electric drill with a set of drills, a hammer. At the same time, it is necessary that the nozzles for screwdrivers are universal, that is, they fit any type of screw or bolt. The same applies to drills. The standard set includes drills that may be useful for working with various materials e.g. wood, concrete, metal.

And over time, these consumables become dull and cannot perform their functions to the required extent. Each of types of drills there are features in sharpening. Some of them can only be sharpened using complex aggregates and equipment. But with such a process as sharpening a drill for wood, you can do it yourself at home. This requires patience and some simple skills.

Independent choice of drill

When choosing and buying drill bits for a drill, first of all, you need to carefully inspect the tool for cracks and other external damage. These defects must be completely absent. By the color of the drill, you can determine how the final processing was performed. The strength and other performance characteristics of the tool depend on this. If the drill is black, then it was treated with high temperature steam, which increases strength.

The position of the drill when sharpening on a grinding wheel.

With a golden yellow color, the drill was processed to relieve stress. When the drill is treated with titanium nitride, the drill acquires a bright yellow color. After titanium sputtering, the period of action is significantly increased. The drill, which is not subjected to any processing, has a dark gray color.

Most often, a drill set is included with a drill. It may include tools of various lengths, diameters, as well as processing methods.

Drills according to their application can be divided into:

• for woodworking;
• for concrete structures;
• for metal parts.

Each type may vary appearance and color. But there are also subtleties. So, for example, to drill a tree, drills can be made in the form of a spiral, serpentine, feather design.

The spiral drill comes in diameters of 3-52 mm. The peculiarity of this tool is that the double band can provide accurate guidance on the hole, regardless of the depth, preventing it from slipping. Chips are removed in a timely manner, clogging of the spiral does not occur. With it, holes are drilled for dowels in monolithic wooden slabs various types of wood, thick plywood sheets, as well as soft wood.

The threaded point, cutter and hex shank are the features of the serpentine drill. The spiral is carefully ground and milled. It is used to make holes in slabs that are lined with veneer.

A drill with a feather tip can be used for domestic purposes for various types of wood. It is very convenient to remove it from the drill clamp if you need to make many holes of various diameters. It can be used to drill through hard or soft wood.

The quality of the resulting hole will directly depend on how correct the choice of the element will be. The drill set should have a long piece to drill through thick wood. It is very important to consider the size of the electric drill. With a length of 45 cm and a diameter of 10 mm, it has sufficient weight even when operating at high speeds conventional drill you may experience discomfort. Therefore, to work with such a drill, it is better to use a mixer drill, which has low speed.

A screw drill can provide work in wood against the grain. Their diameters can be 10-50 mm, length 400-1100 mm. The longer the drill has, the longer it should be threaded. It is she who will provide a simple removal of chips in the process.

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Additional points

As an alternative to a long threaded drill bit, you can use spade bits with an extension to make the required holes. But this type of drill has a significant drawback: with a large hole length, it is difficult to remove chips. This extension has a hexagonal shape and can be used for other types of drills. The diameter of the hole that will be obtained as a result can be 10-52 mm.

For woodworking, in addition to these types (spiral, serpentine, feather design), ring drills are also used. This is a specific type of drill most commonly used for making holes in furniture pieces. In addition, with the help of such drills it is possible to drill holes of a sufficiently large diameter that none of the other types can do. The drill itself has the form of a ring with teeth. Such drills are sold in a set, among which there are nozzles and a base for their fastening.

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Proper sharpening of the drill

When the product is dull, the question arises where. Sharpening yourself is possible, only certain skills are required for this. If there are none, then to acquire them, you can first sharpen elements that are old enough, which, if unsuccessful, can be thrown away. After all, if you do not follow the sharpening technique, then further use product is impossible, as well as restore it. Drills that are designed for woodworking are especially well suited for sharpening at home. This is due to the peculiarity of the execution of this tool, as it is made of softer steel. Then the place where to sharpen the drill will be a home workshop.

Required for sharpening grinding machine which must be constantly supplied with water.

A jet of water will prevent overheating of the metal of the drill during work. If it is not at home, then you can use a file. But processing the drill by hand will require a lot of time and patience.

When performing sharpening, it is necessary to strictly observe the original geometric dimensions and not to violate the configuration features of the tool. Namely, the degree of its preliminary sharpening, which was performed during production.

If a sharpening machine (grindstone) is used, then the process itself is performed by the edge of the grinding disc. In order to maintain the required geometrical accuracy, a special additional tool can be used. A drill is inserted into it and clamped. This will make sharpening work easier and save your hands from possible burns from an overheated drill. To avoid injury to hands, it is recommended to use gloves during operation. After the preliminary sharpening has been completed, it is necessary to bring the cutting edge to an ideal state. This can be done on the same machine, but at a reduced speed. It is after finishing that the drill will be finally sharpened and ready for further operation. Correctly performed sharpening can ensure a long tool life within the requirements: do not make notches in the wood when drilling, remove chips along the body of the drill.

To drill holes in products made of wood, you can use tools of various types, differing in design, material of manufacture and geometric parameters. One of these tools is a drill bit for wood, on the design features and technical specifications which is worth a closer look.

When do you need a special tool for drilling wood

The question of how and what is better to drill a hole in a product made of chipboard, MDF, plywood or solid wood natural wood, is relevant not only for carpentry specialists and those who are professionally engaged in the manufacture of furniture, but also for home craftsmen who prefer to do many housework with their own hands. The choice of wood drills in such cases is made depending on what type of holes need to be drilled:

• deaf, not having an exit from the opposite side of the product (intended for mounting hinges on interior doors or on the doors that are equipped with furniture structures);
• through (they place elements threaded connections(bolts and studs), without these holes it is not possible to install door handles and castles).

For woodworking, you can purchase an expensive tool (such as, for example, disc cutter). However, its use is not justified in all cases. For most wood drilling situations, an easier-to-operate and much more inexpensive tool will do. These are, for example, pen drills, which, despite their affordable cost, are highly efficient in use. You can use a drill bit for wood with a feather, complete with both electric drill, and with a conventional screwdriver.

Main characteristics

When using spade drills for wood, it is desirable to know how they differ from other types of cutting tools and what advantages they have.

Like drills for metal, tools designed for woodworking are available in various designs and, accordingly, differ from each other in characteristics and functionality. When choosing such tools, you should be aware of the advantages and disadvantages that they have.

Ground drills, as can be seen from the presented table, have a number of advantages when compared with other types of tools. Meanwhile, a pen-type tool is not recommended for making large diameter holes (more than 60 mm), as their edges may turn out to be torn. For such purposes, it is better to use core-type drills, which are made in the form of a metal glass with cutting teeth located on its end part.

Due to the low cost of fountain drills for wood, any House master can buy a set. The presence of such a set in the home workshop allows you to easily and quickly select a tool for drilling holes of different diameters.

The spade drill has a very simple design, the elements of which are the working and tail parts.

The working part is a flat blade, in the center of which there is a sharp protrusion used to center the hole being made. On the working part of the pen drills there are two cutting blades located on both sides of the central ledge. Each of these blades starts from the tip of the central protrusion and reaches one of the edges of the working part. The slope of sharpening the blades of drill bits for wood, if you look at their working part in cross section, is performed to the right. In the manufacture of drills of this type, manufacturers adhere to certain ratios between the thickness and width of the cutting part.

The tail part is made in the form of a hexagon. This cross-sectional shape allows not only to securely fix the tool in the chucks of drills and screwdrivers, but also to use magnetic adapters and extension cords for this purpose.

Simplicity of design, which distinguishes drills related to feathers, the absence of spiral grooves, ribbons and other complex elements are not indicators of the low effectiveness of this tool.

When choosing a pen-type drill designed for woodworking, you should pay attention to several parameters:

1. the correctness of the form (the feathers of the wood drill, located on the right and left sides of the central protrusion, must be symmetrical and the same in their linear dimensions);
2. the degree of sharpness of the cutting part (sharpening of new fountain drills must be carried out in the factory and correspond to standard requirements);
3. absence of visible defects (if there are visible defects of a different nature on the surface of a new drill, this is a clear indicator of the low quality of such a product, most likely produced in artisanal conditions);
4. color (by the color of the metal, you can determine the types of additional processing that the finished product has been subjected to).

Operating rules

In order to increase the efficiency of the use of spade drills for wood and extend their service life, the following recommendations must be followed when processing.

1. Markings must be applied to those parts of the product where future holes will be located.
2. It is better to choose a drill with a power regulator as equipment that will be used complete with a pen drill.
3. Drilling wood with spade drills is performed at a low rotation speed (200–500 rpm). The specific value of the drill rotation speed depends on the diameter of the hole being made: the larger it is, the slower the tool should rotate.
4. When the length of the spade drill is not enough to make a deep hole, special adapters are needed that are installed in the chuck of the equipment used. Otherwise, such an adapter is not required.
5. Before starting drilling, the tool is brought to the surface to be treated strictly at an angle of 90 °, while its sharp protrusion should be located exactly in the center of the future hole.
6. Drilling should be started at low speed, and as the drill goes deeper into the tree, the rotation speed can be increased.
7. Chips that accumulate in the created hole must be periodically removed from it. As soon as you notice that too much chips have accumulated, you need to stop drilling, remove the drill from the hole and remove the processing waste.
8. As soon as the tool plunges into the hole to be created to the required depth, the drilling process can be stopped.

How to sharpen drill bits

Unlike drilling tools other types, fountain drills designed for woodworking are sharpened quite simply. To perform this procedure, you can use grinder equipped with a diamond wheel. If such equipment is not at your disposal, a quality rule will do. The sharpening procedure itself is as follows.

• If the master has a set of pen drills, a new, not yet used tool is taken from it, which will act as a sample.
• Focusing on the geometric parameters of the sample, sharpen the cutting part of a dull drill.
• When sharpening a pen drill for woodworking, you should be very careful not to accidentally damage its central ledge.

It makes no sense to sharpen pen drills in cases where their cutting part has been ground off too much. Given their low cost, heavily worn products are easier to replace with new ones than to try to return them to working condition.

The modern market offers customers a huge number of drills different types. Some of them are used exclusively for wooden structures, let's figure out how to choose them correctly and how to sharpen a wood drill in the best way.

When it becomes necessary to choose the right drill, the first thing you need to pay attention to is the color. So, for example, each shade of the product is responsible for the type of finish, showing the life of the drill and its strength.

• The worst option can be considered gray products that are not processed by anything and their performance parameters are quite low.
• The color can be golden, which indicates titanium plating and enough long term operation.
• No worse in terms of performance and black drills, processed when creating steam.

In addition, it is worth carefully visually examining the object. If traces of deformation are noticeable on it, then it is better not to use such a product. It is important to choose a drill without a single scratch or crack, its surface must be perfectly flat and smooth.

Types of drill for wood

Usually high-quality drills are used experienced craftsmen who need to work Various types products for making holes in wood. These can be holes, for example, for spikes, bolts or dowels. Moreover, the drilling process itself can be very diverse in quality, which will entail thoughts about how to properly sharpen the drill after operation and whether it will have to be sharpened at all.

The most common types of drills today include: helical, twist, spade, center, annular and Forstner drills.

screw

If you want to drill wood across the grain without specifying once again the question of how to properly sharpen a drill for wood, then a screw drill with a fine thread at the end will come in handy. In diameter, they can reach up to 50 millimeters. A special screw shape will help to remove chips from the place of work in time and thereby not overheat the core. Depending on the required hole depth, drills over a centimeter long can be purchased, while minimum size- 400 millimeters.

Spiral

A spiral product can be immediately distinguished by a perfectly ground milled spiral with a point that prevents any movement of the rod to the side during operation. It is thanks to the spiral shape that holes are easily drilled in veneer structures. In diameter, the corresponding drills reach 52 millimeters, and the smallest can be found at 3 millimeters. In order to accurately aim at the intended drilling site, the tail of the product is equipped with a conical shape, which gives a lot of convenience.

If during the purchase the choice fell on twist drills, then you should always remember the relationship between the diameter of the product and maximum number RPM it can deliver. Otherwise, the service life of the product will be drastically reduced. If you want to process hard wooden surfaces, then it is better to set a maximum of 900 rpm with a drill diameter of 14 millimeters or less. But for soft wood, you can install 1800 revolutions on a drilling tool.

Feather

The most common type of drill is the feather drill. It is it that suggests how to sharpen a drill bit for wood, and is most often used for repair and construction work. It is the most convenient and various options in diameter.

It has only one important drawback: this shape of the drill does not contribute to chip removal and the drilling process is much more complicated, especially when a hole with a large depth is needed. That is why experts recommend using this type of drill when working with wood-based panels or thick boards, where the drilling process will take place as efficiently as possible.

The situation can be corrected by a special type of tip for a feather drill or a similar product with an extension cord. Such an extension has a hexagonal shape, and may well be used for other types of drills. In this case, the diameter of the final hole can reach up to 52 millimeters.

Center and ring

But center drills are useful for creating perfectly even through holes in wooden surface. Typically, such products have the form of a 50 mm (minimum - 12 mm) rod with a cutting edge at the bottom, reaching a length of up to 150 millimeters. Of course, deep enough holes will not work. For this, ring drills are suitable, which look similar to a crown or a ring with teeth. Usually they are sold as a set in the form of nozzles with a center drill and a single base.

Forstner drills

When it comes to repairing or creating furniture, and not thinking about how to sharpen a spade bit for wood, then you can immediately go for Forstner drills, which are best suited for this business. They allow you to drill completely blind holes with a perfectly flat bottom. In this case, the diameter of the product reaches from 10 to 50 millimeters. The drill itself is covered with a specialized alloy that serves as protection and increases the service life.

Proper sharpening of the drill

Before proceeding directly to sharpening an expensive and high-quality drill, you should try your skills on old, used products. Thus, with a negative result, the old drill can always be put on consumable. When the hand is full, you can switch to a new drill without fear.

For the most correct sharpening of the drill on wood, its geometric parameters should be observed. This means that it is important to maintain the factory sharpening angle. Sometimes the result can be like this - perfectly sharpened for a puncher. The drill itself can be processed both manually and with the help of an electric grinder.

Manual sharpening

At manual sharpening a mild steel file is used. Moreover, it is worth starting the processing process with a tool with a wide notch pitch, processing both the cutting edge and reverse side. After that, you can bring the drill to an ideal state with a file with a fine notch.

Sharpening with an electric sharpener

When the drill is sharpened in “automatic” mode using an electric grinder, it is very important to have nearby cold water(in a container or flowing), as it is necessary to constantly cool the rod. This will keep the product from overheating and damage.

With this option, the drill should be sharpened on the edge of the sharpener disk.

Homemade drill sharpening machine

In the case when there is no sharpening machine at hand, it is quite possible to do it yourself.

1. It is necessary to firmly install the angle grinder in a comfortable position. A stationary frame with a motor frequency of up to 1500 rpm (with a power of 200 W) is also suitable.
2. Basis for homemade machine thick plywood or a wooden beam may well serve.
3. For more correct sharpening, it is necessary to exclude any vibration of the engine and create conditions for smooth transition for different speeds. To achieve this result, you can use an abrasive wheel.

Step-by-step instructions for sharpening a drill

The result of the above actions is a certain scheme of actions:

1. The eyeliner of the drill to the edge of the disk of the grinding machine.
2. Mandatory observance of the factory sharpening angle equal to 95 degrees.
3. To improve the quality of sharpening, the drill should be fixed in a washer, the rear edges of which must be tucked a couple of millimeters.
4. As soon as sharpening is over, it is worth continuing to work at lower speeds.
5. After that, you can cool the sharpened product and test for performance.

When sharpening a drill, it is important to understand that a person needs to have very good eyesight. Therefore, for best result need to organize quality lighting places of work. In case of strict observance of the rules, a sharpened drill will last a very long time and will always be a “salvation” during repair or construction work.