How to sharpen a twist drill bit for wood. How to properly sharpen a drill at home. A few words about repairing concrete drills

Wood is a material that is easily processed various instruments. One of their types may be a drill. You have to use a drill quite often when processing material.

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

For small sizes, a metal tool is usually used, but for larger diameters, a specialized large-diameter wood drill is used.

There are several types:

There are, but are rarely used, drills for cutting conical tenons, cork drills, etc., etc. Let's look at some of them.

Twisted or single-stranded

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

Used to perform deep holes. Using this tool, the holes are even, smooth and neat.

Ballerina

It is an adjustable device with cutters. The gimlet in the center carries out preliminary 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 You can't make deep holes. Maximum size the holes do not exceed 300 millimeters.

Crown

Used for drilling shallow through holes. A disk is used as a base, 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 bit for wood

The Forstner drill is mainly used for furniture production, for drilling holes of precise diameter. It makes it easy to make a blind hole. The cutters are available in different diameters work surface: 10, 16, 24, 27, 32, 36, 38, 40, 45, 50 (mm). The price depends on the diameter, the larger it is, the higher the price.

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

Feather drill

Quite often, feather drills are used for drilling any type of wood.

A 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 feather drill is as follows:

• low price;
• good diameter selection step;
• easy to use, no pre-coring required;
• high performance;
• possibility of using an extension cord.

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

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 shape of a blade, which has two specially shaped cutting blades sharpened on its sides. Thanks to this shape, the blade cuts into the wood, removing chips around the circumference. In order for the drill to be stable during operation, a centering point is made at its very center below the blade.

By their type, drills can be single-sided or double-sided. The bevel angle of the cutter for one-sided is 70−90 degrees, and for double-sided it is 115−135 degrees.

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

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

At points of sale you can purchase both a set of feather drills for wood and single ones. They are produced different sizes diameter On the blade there is a number indicating the diameter of the hole in millimeters that it can make, for example, 50. The maximum usable diameter is sixty millimeters. No longer produced, as the tool would 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 processed with internal pressure removal.
• 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 adjustable speed. They must be set to medium mode, since when working on high speed the likelihood of drill breakage increases. It should be noted that the rule is that larger diameter drills, the lower the rotation speed needs to be set.

During operation, the middle of the drill should be set strictly perpendicular to the workpiece, the pressing force is light. The chips that appear in the hole created, 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 pen drill. 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, using a power tool.

How to sharpen a feather drill?

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

Any abrasive material can be used for sharpening. Sharpening can be done manually or on a machine. It is best to sharpen the cutters according to the sample, and try to sharpen the tip in the center. When sharpening a pen drill for woodworking, you must be very careful not to accidentally damage the tip.

After finishing the sharpening process, it is necessary to perform a test drilling and, if necessary, adjust the cutting blades or alignment.

To summarize, it should be noted: the choice of 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 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 executed from quality materials, which will ensure a clean cut and a longer service life.

The Lewis drill is designed to produce deep, small-diameter holes in wood of various species with any degree of humidity. The screw-shaped cutting edge of the drill begins with a sharp tip, with the help of which 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 basic tool kit of a professional carpenter, being lightweight, 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. A shank that 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 a constant cross-section and a relatively small angle of inclination. For the Lewis spiral, it is selected 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 reducing the axial load during the operation. For a tool of relatively low rigidity (and a twist drill is just that), high axial loads become the main cause of failure.

Due to the complexity of the Lewis drill profile along its length, such equipment is almost never manufactured in a welded version. The material is high-speed steel grades 10Р6М5, Р6М3 and the like, according to GOST 19265-74.

A special feature of the Lewis spiral is its single-thread nature, which provides the drill with the ability to spontaneously retract into the cavity of the resulting hole. At the same time, the direction of the drill improves, 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, is embedded deeper. Then the main, spiral part of the drill rests on it. Unlike other designs of wood drills, the tool in question initially has only one working edge, and then drilling occurs with a spiral cutting part. By increasing the total length of the cutting edge, this helps to reduce the total axial force on the drill, but increases the risk of jamming and “driving” of the drill from the center.

The first problem is solved as follows. Firstly, it is preferable to install a Lewis drill on low-speed, more powerful drills. Secondly, such spiral-like drills are inappropriate to use for making holes in hardwood, since the resulting chips contribute to jamming the waste in a rather long groove. Typically, the number of revolutions is chosen inversely proportional to the diameter of the resulting hole.

To solve the second problem, a twist drill can be used as a reamer, and the preliminary pass, with the exception of particularly deep holes, can be performed using a regular drill. From operating experience it is known that direct production of holes using a Lewis drill is advisable for diameters not exceeding 15...30 mm. In other cases they use feather drills, and spiral is used only on the last pass, when it is necessary to increase the smoothness of the side walls.

The moisture content of the wood does not matter when using such a drill, nor does the direction of the wood grain.

Features of use

Among the advantages of Lewis drills it should be noted:

1. Smooth increase in work 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 outward by the auger generatrix of the drill.
3. The wide helical flute ensures reliable removal of chips, regardless of their quantity.
4. The hexagonal tip on the shank ensures reliable retention of the drill in the chuck.

High quality and productivity, especially noticeable when producing holes of significant depth, do not cancel out some of the limitations of twist drills:

1. If the Lewis drill jams, which is possible in operations with hardwood, its stopping occurs almost instantly, and is accompanied by a sharp recoil. This could result in injury to the worker.
2. Since the cutting forces during such drilling are high, the quality of the material is decisive for the durability of the auger drill. Therefore, it is worth purchasing tools from well-known manufacturers who indicate the steel grade (the grade is usually not indicated on Chinese-made drills).
3. A twist drill has increased fragility, since during hardening it is usually calcined over the entire cross-section. With relatively low rigidity, this can cause destruction of the working part.
4. The cost of Lewis drills is higher than regular ones, with the same diameters of the resulting holes.
5. Low-power drills (less than 1000 W) may not be able to turn a drill of this design when started. It is also important that the drill has a reverse function.

How to sharpen a Lewis drill?

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

• When single-plane sharpening, the back angle of the drill is given a value of 28...32º using 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 small diameter twist drills;
• When 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 edge, and with the left - screw part drills, and as close as possible to the cone. By rocking 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 part;
• If it was not possible to maintain the required parameters, the Lewis drill can be sharpened. For this purpose, the rake angle is reduced and the width of the cutting band is increased. True, the drill cannot be used with the same efficiency for drilling tough wood with high humidity;
• At the final stage, the drill is fine-tuned, which consists of removing all identified marks and nicks, after which the conical thread on the tip is restored.

Working with Lewis drills must be done with some experience, since this design The tool is very sensitive to 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, and a hammer. In this case, it is necessary that the screwdriver attachments be universal, that is, suitable for 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, for example, 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 sophisticated machinery and equipment. But you can handle the process of sharpening a wood drill yourself at home. This requires patience and some simple skills.

Independent choice of drill

When choosing and purchasing 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.

When the color was golden yellow, the drill was treated to relieve stress. When a drill is treated with titanium nitride, the drill becomes bright yellow. After titanium coating, the service life increases significantly. The drill, which is not subjected to any processing, has a dark gray color.

Most often, a drill comes with a set of drills. It may include tools of various lengths, diameters, and processing methods.

Drills according to their application can be divided into:

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

Each type may differ in appearance and color. But there are also subtleties. So, for example, to drill wood, drills can be made in the form of a spiral, serpentine, or feather-shaped.

The twist drill comes in diameters of 3-52 mm. The special feature of this tool is that the double tape can ensure precise guidance along the hole, regardless of the depth, preventing it from slipping. The chips are removed in a timely manner and the spiral does not become clogged. It is used to drill holes for dowels in monolithic wooden slabs various types of wood, thick plywood sheets, as well as soft wood.

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

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

The quality of the resulting hole will directly depend on how correct the choice of element turns out to be. Your drill kit 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 a regular drill You may experience discomfort. Therefore, to work with such a drill, it is better to use a drill mixer that has low speed.

A twist drill bit can work against the grain in wood. Their diameters can be 10-50 mm, length 400-1100 mm. The longer the drill, the longer it should be equipped with threads. It is this that will ensure easy removal of chips during operation.

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Additional points

As an alternative to a long threaded drill, you can use feather drills with an extension to make the necessary 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 type), ring drills are also used. This is a specific type of drill that is most often used for making holes in furniture parts. In addition, with the help of such drills you can drill holes of a sufficiently large diameter that none of the other types can do. The drill itself looks like a ring with teeth. Such drills are sold in a set, which includes attachments and a base for attaching them.

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Correct sharpening of the drill

When the product becomes dull, the question arises, where. Sharpening yourself is possible, but this requires certain skills. If there are none, then to acquire them you can first sharpen elements that are quite old, which can be thrown away if unsuccessful. After all, if you do not follow the sharpening technique, then further use It is impossible to restore the product, nor can it be restored. Drills designed for woodworking are especially easy to sharpen at home. This is due to the peculiarity of the design of this instrument, as it is made of softer steel. Then the place to sharpen the drill will be your home workshop.

Required for sharpening sharpening machine, to which water must be constantly supplied.

A jet of water will prevent the drill metal from overheating while performing work. If you don’t have it at home, you can use a file. But processing the drill by hand will require a lot of time and patience.

When sharpening, you must strictly observe the original geometric dimensions and not disturb the configuration features of the tool. Namely, the degree of its preliminary sharpening, which was performed during production.

If a sharpening machine (sharpener) is used, then the process itself is performed with the edge of a sharpening disk. To maintain the required accuracy of geometric values, you can use a special additional tool. A drill is inserted into it and clamped. This will make the sharpening job easier and protect your hands from possible burns from an overheated drill. To avoid injury to your hands, it is recommended to use gloves while working. After the preliminary sharpening has been completed, it is necessary to bring the cutting edge to perfect condition. This can be done on the same machine, but at reduced speed. It is after finishing that the drill will be finally sharpened and ready for further use. Correctly performed sharpening can ensure a long service life of the tool within the limits of the requirements: do not make nicks 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 wood drill bit, based on the design features and technical specifications which is worth dwelling on in more detail.

When do you need a special tool for drilling wood?

The question is how and what is the best way 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 professionally make furniture, but also for home craftsmen who prefer to do many of the housework with their own hands. The choice of drills for wood in such cases is made depending on what type of holes need to be drilled:

• blind, having no exit on the opposite side of the product (intended for mounting hinges on interior doors or on doors that are equipped with furniture structures);
• end-to-end (they contain elements threaded connections(bolts and studs), without such holes it is impossible to install door handles and locks).

For woodworking, you can purchase expensive tools (such as disk cutter). However, its use is not justified in all cases. For most situations where wood needs to be drilled, a tool that is easier to use and significantly less expensive will do the job. These are, for example, feather drills, which, despite their affordable cost, are highly efficient in use. You can use a feather drill for wood in combination with both electric drill, and with a conventional screwdriver.

Main characteristics

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

Like metal drills, 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 have an idea of ​​the advantages and disadvantages they have.

Feather drills, as can be seen from the table presented, 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), since their edges may turn out torn. For such purposes, it is better to use core drills, which are made in the shape of a metal cup with cutting teeth located on its end part.

Due to the low cost of feather drills for wood, any House master can buy a set of them. Having such a set in your home workshop makes it easy and quick to select a tool for drilling holes of different diameters.

The tip 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 either side of the central protrusion. Each of these blades starts from the tip of the central protrusion and reaches one of the edges of the working part. The tilt of sharpening the blades of feather drills for wood, if you look at their working part in cross section, is done to the right. When making 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 shape 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 extensions for these purposes.

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

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

1. correctness of shape (wood drill feathers located on the right and left sides of the central protrusion must be symmetrical and identical in their linear dimensions);
2. degree of sharpness of the cutting part (sharpening of new pen drills must be carried out in the factory and correspond to standard requirements);
3. absence of visible defects (if the surface of a new drill contains visible defects of various types, 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 to which the finished product has been subjected).

Operating rules

To increase the efficiency of using pen drills for wood and extend their service life, when performing processing, you must adhere to the following recommendations.

1. Markings must be applied to those areas of the product where future holes will be located.
2. For equipment that will be used in conjunction with a pen drill, it is better to choose a drill with a power regulator.
3. Drilling wood using feather 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 pen 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 processed strictly at an angle of 90°, while its sharp protrusion should be located exactly in the center of the future hole.
6. Drilling should begin at low speeds, and as the drill deepens into the wood, the rotation speed can be increased.
7. Chips that accumulate in the hole being created must be periodically removed from it. As soon as you notice that too many 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 is immersed in the hole being created to the required depth, the drilling process can be stopped.

How to sharpen feather drills

Unlike drilling tools other types, pen drills intended 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 craftsman has a set of feather drills, a new, unused tool is taken from it, which will act as a sample.
• Focusing on the geometric parameters of the sample, sharpen the cutting part of the dull drill.
• When sharpening a pen drill for woodworking, you should be very careful not to accidentally damage its central protrusion.

It makes no sense to sharpen feather drills in cases where their cutting part is sharpened too much. Given their low cost, it is easier to replace heavily worn-out products 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 final processing, which shows the life of the drill and its strength.

• The worst option can be considered gray products, which are not processed in any way and their performance parameters are quite low.
• The color can be golden, which indicates titanium coating and is quite long term operation.
• Black drills treated with steam during creation are no worse in performance.

In addition, it is worth carefully visually examining the object. If there are visible signs of deformation 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 should be perfectly flat and smooth.

Types of wood drills

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

The most common types of drills today include: screw, spiral, feather, center, ring and Forstner drills.

Screw

If you need to drill wood across the grain without asking once again If you are wondering how to properly sharpen a drill for wood, then a screw drill with a fine thread at the end will come in handy. They can reach up to 50 millimeters in diameter. A special screw shape will help remove chips from the work site in a timely manner and thus not overheat the rod. Depending on the required hole depth, you can purchase drills longer than a centimeter, while minimum size– 400 millimeters.

Spiral

A spiral product can immediately be distinguished by a perfectly polished milled spiral with an edge that prevents any movement of the rod to the side during operation. It is thanks to the spiral shape that they can easily drill holes in veneer structures. The diameter of the corresponding drills reaches 52 millimeters, and the smallest can be found at 3 millimeters. In order to accurately target the intended drilling location, the tail of the product is equipped with a conical shape, which gives a lot of convenience.

If, when purchasing, the choice fell on twist drills, then you should always remember the relationship between the diameter of the product and maximum quantity rpm it can produce. Otherwise, the service life of the product will be sharply reduced. If you need to process hard wooden surfaces, 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 set the drilling tool to 1800 rpm.

Feathers

The most common type of drill is the feather drill. It is this that makes you think about how to sharpen a feather drill for wood, and is most often used for repair and construction work. It is the most convenient and has various options in diameter.

It has only one important drawback: this shape of the drill does not facilitate chip removal and the drilling process becomes significantly 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 boards or thick boards, where the drilling process will occur as efficiently as possible.

A special type of tip for a feather drill or a similar product with an extension can correct the situation. This extension has a hexagonal shape and can 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 smooth through holes in wooden surface. Typically, such products take the form of a 50 mm (minimum 12 mm) rod with a cutting edge at the bottom, reaching a length of up to 150 mm. Of course, it will not be possible to make deep enough holes. For this purpose, ring drills are suitable, which look similar to a crown or a ring with teeth. They are usually sold as a whole set in the form of attachments with a centering drill and a single base.

Forstner drills

When it comes to repairing or creating furniture, and not about thoughts with the question of how to sharpen a feather drill for wood, then you can immediately safely go for Forstner drills, which are best suited for this task. 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 coated with a specialized alloy, which serves as protection and increases service life.

Correct sharpening of the drill

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

For the most correct sharpening of a wood drill, its geometric parameters should be observed. This means that it is important to maintain the factory sharpening angle. Sometimes the result can be just like this – perfectly sharpened for a hammer drill. The drill itself can be processed either manually or using an electric sharpener.

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 this, you can bring the drill to perfect condition using a file with a fine notch.

Sharpening with an electric sharpener

When sharpening a drill occurs in “automatic” mode using an electric sharpener, it is very important to have a cold water(in a container or flow-through), since 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 sharpening disk.

Homemade drill sharpening machine

If you don’t have a sharpening machine at hand, you can easily make one yourself.

1. It is necessary to firmly install the grinder in a comfortable position. A stationary frame with a motor speed of up to 1500 rpm (with a power of 200 W) is also suitable.
2. Basis for homemade machine Thick plywood or wooden beams may well serve.
3. For more correct sharpening, it is necessary to eliminate any engine vibration and create conditions for smooth transition at 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. Guide the drill to the edge of the grinding machine disc.
2. Mandatory adherence to the factory sharpening angle of 95 degrees.
3. To improve the quality of sharpening, the drill should be secured in a washer, the rear edges of which should be tucked a couple of millimeters.
4. Once sharpening is completed, it is worth continuing work at lower speeds.
5. After this, you can cool the sharpened product and test it for functionality.

When sharpening a drill, it is important to understand that a person must have very good eyesight. Therefore for best result needs to be organized quality lighting places of work. If the rules are strictly followed, a sharpened drill will last a very long time and will always be a “savior” during repair or construction work.