Drill sharpening can be done manually, on machines or special abrasive discs.

If you are sharpening the drill by hand, then it is necessary:

• hold firmly by the shank, and with the other hand guide its spiral part;
• press the cutting edge of the drill to the side surface of the abrasive wheel;
• after sharpening one side, it is necessary to smoothly turn the drill, while the cutting edges must necessarily have the correct inclination to the axis and take the desired configuration.

The drill is sharpened alternately on both sides. When doing this, be sure to check the cutting edges.

Remember! The point of the drill should be exactly in the center.

V otherwise it will deviate during operation. It should be noted that in no case should you press hard on the drill, otherwise it may get defects (bending).

For example, if after sharpening, you notice that the cutting edges are uneven and sloped under different angles to the axis, this means that the middle of the cross edge is not in the center of the drill, and it will not work correctly.

When sharpening, be sure to pay attention to the initial angle of the tool. It is he who will become your guideline in the future. Then inspect the gimbal for damage:

• if you find serious defects, then you can use coarse sandpaper;
• if the defects are small and the drill is just a little dull, use a lapping wheel. This operation is necessary for thin drills;
• if a drill for concrete has defects in the shank taper - process the upper part of the tool, gently pressing it against the grinding wheel;
• after processing, carefully inspect the back surface of the drill again;
• if you notice, or determine with a template that you have got a perfect taper, you have sharpened the tool correctly.

Then work the cutting edge of the drill. The size of the jumper for rational turning of the tool should be 1-1.7 mm.

What are the features of grinding machines

The self-made device for sharpening drills is designed for through and blind gimbals made of steel, cast iron and various hard alloys. Depending on the type, the machines can be provided with different functions. On some of them, the angle can be varied during operation.

Sharpening machines are:

• universal - used for various cutting tools;
• specialized - for one type.

It is to universal machines include devices for sharpening drills, because they can handle:

• taps;
• cutters;
• dumbbells;
• countersinks.

Machine tools fall into two categories:

1. Industrial - have high power and are designed for sharpening tools large diameter... The power depends directly on the engine.
2. A household drill grinder is quite compact and is often used for home use. Even small-diameter drills can be processed with it.

There are seven sharpening methods:

1. One-plane.
2. Complicated screw.
3. Shaped.
4. Elliptical.
5. Conical.
6. Two-plane.
7. Screw.

How to make a drill sharpener

To make a homemade machine tool, you will need:

• toggle switch;
• abrasive wheel;
• plug;
• engine;
• stand;
• wires.

Follow our advice:

1. For security, place homemade machine into the body, leave only the axle and the abrasive disc outside. Remember, the device will operate on mains power.
2. In advance, choose a place where your drill sharpener will stand. It is desirable that it be on a metal table.
3. Next, place the electric motor on the tabletop using fasteners (clamps) and mark the locations of the holes for the bolts, if it has legs.
4. Then remove the motor and make 4 holes.
5. Reinstall the motor later and secure it carefully with the bolts.

Advice: If the engine does not have legs, you can strengthen it with metal strips (clamps).

The electric motor for our future machine should be equipped with a special elongated shaft, on which a granular disc should be put on. For this:

1. Install the retaining nut, having previously cut the right-hand thread on the end of the shaft.
2. Secure the disc with washer and nuts.

If the diameter of the shaft and the bore of the disc are the same, install a washer and then an abrasive disc on the shaft. If the diameter of the shaft and the hole do not match, then you need to add a bushing.

First, make a special side hole with a thread for the bolt in it so that you can firmly fix it on the shaft. Then you can put on the sleeve.

If you cannot decide on an electric motor, then just take the old motor washing machine... It is ideal for homemade device sharpening.

It is worth noting that you must prepare the starter and the wires in advance, which will subsequently need to be connected. It is very important that the starter has at least three to four open contacts. Its winding must be connected with two buttons to the phase line.

Attention! The electric motor will be unsafe, regardless of the type - during operation, the rotating shaft can accidentally wind up the cord, wire, hair.

Advice: Make a metal box to protect the machine from dust, abrasive particles, and you from accidental injury.

How to sharpen a drill correctly on a machine

1. When sharpening, make sure that the two drill shoulders are the same. If you achieve such a match, then the axis of rotation of the drill will completely coincide with the center of the hole.
2. Always make sure the abrasive wheel is firmly attached before sharpening.
3. Always start the process with a coarser abrasive. After the burr appears on your drill, you can change the abrasive to a finer one.
4. Watch your sharpening angle.
5. Do not switch the windings to reverse the abrasive wheel. It should always only move in the direction of the blade.

Please note that drills cannot tolerate excessive heat build-up. Cool the gimbal regularly while sharpening. But in no case immerse a red-hot drill in water, as cavities may appear in it.

Additional accessories

1. Guide

To avoid holding the drill bit while sharpening (this can lead to injury), provide a backing or guide in the form of a small attachment. It is made from a strip of metal, bent as shown in the figure and screwed to the bed (base). The drill is supported on it and brought to the circle at the desired angle.

1. Protractor

Make on the guide described above, marks (marks) at the required sharpening angles. It will become much more convenient to use it.

If this is difficult for you, cut off the top of a regular protractor and glue it onto the guide.

Angles less than 30 0 are not used for sharpening, so we sacrifice them.

1. Universal fixture

To facilitate sharpening of tools, in particular drills, a mechanism has been developed that consists of a drill chuck, a shaft, roller guides (slide) and a protractor.

The main substrate described above is made wide. A protractor is glued to it. A hole is drilled into which a bolt is inserted, which serves as an axis for the pivot surface.

A plate is installed on it on a roller slide, on which a pipe with a chuck on the axis is fixed. The plate itself moves forward / backward using a conventional feed mechanism (threaded axle).

In the lower part of the swivel plate, an offset stop indicator is fixed. It serves to rotate the device to the desired angle and to stop it.

Working with the fixture

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

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

Drill sharpening features

Drills are inexpensive tools, especially when it comes to those that are widely used for domestic needs. However, if there is a possibility, then after blunting it is better to sharpen the tools than to buy new ones.

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

It is worth noting that bluntness concerns drills for metal, since wood tools are practically not susceptible to this, with the exception of cases of use at high speeds with a resinous workpiece. Also cannot be sharpened victorious tips for stone or concrete.

But many people sharpen metal drills with all the additional devices with their 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 tool for sharpening drills with your own hands: a training video

To make such a device yourself, you need a control tool (template). Whichever way the drill is sharpened, the accuracy is checked with 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 differ:

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

A simple but very convenient dragging device is bushings different sizes that are attached to the base. You can make them yourself, based on special drawings. Remember that the tool in the sleeve should not wobble and the drilling quality 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 block from soft material and make many holes in it. It is very important to put a handy tool in the sharpener, thanks to which it will be possible to move the sharpening device at the desired angle and hold the stop.

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

The simplest sharpening machine can be assembled by simply placing a workbench or table in front of the side of the emery. Even such a simple device ensures 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 need to understand the principle of working with a drill.

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

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

Sharpening can be accompanied by the following errors:

How from improvised means with your own hands assemble a twist drill grinder for metal?

For the basis of the device, you can take any grinding machine that is able to work properly, there is no axle runout, and it keeps the revolutions under load.

The task looks like this:

• the handcuff is obliged to stand strictly horizontally on one axis with the rotation of the emery;
• the structure must be safe, reliable and durable;
• it should be possible to sharpen both manually and semiautomatic;
• the shape of the hand-hand should facilitate the free lowering of the drill shank to the desired angle.

No specific parts are required for the manufacture of this device; almost everyone has everything you need. home master... Workpieces are processed grinder, welding or sharpener.

For the semi-automatic mode, an oscillating stop is assumed, so a loop connection must be made. Match exactly for lack of backlash bolt, bracket and tube holes.

The site must move on the vertical axis so that you can change the angle of sharpening of the drill. This axis can be fixed, and the handlebar must swing, while resting on the horizontal axis, which, when sharpened, provides the desired articulation.

Base plate is made of metal 4 mm in thickness, and the main parts of the structure should have a thickness of 3 mm, respectively. This ensures its high strength. The handrail is rigidly connected to the emery body. It is impossible to attach it to the protective casing, therefore, screw the bracket using the metal "cheek".

Then screw the guide plate itself 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 a rotation angle of 90 degrees, which makes it possible to ensure atochku different methods ... Starting from the Leontief method and ending with a clamp 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 at the same time. Due to the partial excess of the plane of the base plate over the axis of movement of the disc, it is possible to achieve the desired shape sharpening the nape of the edge.

Before performing work, the drill should press against the plate and set the cutting edge parallel to it. This is the end of the adjustment and you can bring the tool to the emery. Sharpening should be done slowly and carefully, carefully following the angle.

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

But if you need to sharpen a drill equipped with a carbide tip, you can attach a swinging plate to a fixed angle. For this, several washers are placed under the axle nut.

Using an emery wheel in a homemade sharpening tool

For general-purpose grinding work, white corundum-based circles are mainly used. They are used for sharpening shovels, axes, knives and metal blanks.

For the purpose of machining carbide drills or high-speed metals, abrasive green silicon carbide wheels marked 64C should be taken. But for household needs, a circle grain size of 25N is enough.

Sharpening drills requires a finer fraction in the area from 8H to 16H... Remember that silicon carbide emery stones get 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 sets and chill it in soda water.

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

Peripheral emery surface during processing must be flat. It can be adjusted with an elbor-based attachment. If the disc has a small diameter, pliers can be used to hold the CBN cutter.

So, we looked at how at home you can assemble and use devices of varying complexity for the purpose of sharpening drills and more. Select suitable option you can depending on your household needs.

In principle, you can manually bring a blunt tool into proper condition. But how high will the speed and accuracy be with this technology? Also, if the drill bit is carbide, it can be difficult to do. The author suggests assembling a drill sharpening machine with his own hands, which will allow you to use them repeatedly.

Industrial equipment is quite expensive - from 43,900 rubles.

True, Chinese products (for example, "GQ-D13") can be bought for 6,800 - 7,200.

But such cheap models are unlikely to suit a home craftsman, given that the case is made of plastic, and the engine power is within the range of 80 - 120 watts. In addition, only certain types of drills can be sharpened on them, so there is no need to talk about the versatility of use. Therefore, such machines do not count. The feasibility of making a do-it-yourself "sharpener" for domestic use is more than obvious.

This article does not consider options for making a grinding machine based on angle grinders (there is not a "grinder" in every home, and hardly anyone will buy it for these purposes only) or an electric drill (for which you will have to look for special devices in stores). The simplest and most convenient option is the traditional "sharpener" made of scrap materials, which almost any of us have encountered, and more than once.

There is nothing complicated in the design of such a machine. However, there are a number of features in assembling it with your own hands, and this is what the author draws attention to. Having dealt with all the nuances, it will not be difficult to make an installation for the "home" use of labor ().

What you need to build

El / engine

Various drills, including those of large diameter, are sharpened on the machine in everyday life. In addition, the primary processing of the cutting edges of the tool and their finishing is separate stages work. Therefore, you will have to change the circle and put the one that is at hand from the previously purchased ones. Since the machine is a long-term equipment, it is necessary to mount it for the future. Based on this:

• engine power: about 1.2 - 1.5 kW is enough;
• power supply: single-phase. Any garage or small workshop (shed) on the site, with rare exceptions, is connected to the 1f 220/50 line. This should be the starting point.

Sharpening wheel

Moreover, there should be several of them, with different grain sizes. For reliable fixation of the abrasive on the engine shaft, bushings are prepared that clamp it on both sides.

Sharpening device

You can limit yourself to the simplest "shelf", but then you will not be able to maintain the required angle. This kind of work requires a lot of practical experience.

The device can be purchased, although it is quite rare on sale.

The best option is to make it yourself. For example, these are:

Elements of the scheme

• Magnetic starter (with 3 pairs of contacts) for a 3-phase circuit.
• Button "start / stop" or 2 different - for turning on and off the machine. And the third is obligatory - emergency stop... It is often combined with a pedal, which is much more convenient and safer, since the hands will be busy when sharpening the drills.
• Wires. At the specified engine power, it is enough for 1 "square".

The simplest connection diagrams for three-phase motors are shown in the figures:

An acceptable one is easy to find on the Internet, depending on what kind of motor is used, how its windings are connected ("star" or "triangle"), to which voltage source it will be connected (1 or 3 phases).

Protection elements

• Shroud over the circle.
• Screen (desirable).

There are certain types of work in which the drills are sharpened only on machine equipment, and not manually.

• When drilling to deeper depths where light re-sharpening is required.
• If the drills are universal, they can work even with materials of high density.
• For making blind holes with a special tool.

It is not recommended to sharpen drills using a grinder for several reasons. Firstly, angle grinders are unlikely to be securely fixed. Secondly, the accuracy will be unsatisfactory. Thirdly, after the end of such sharpening, it is rather difficult to make the correct fine-tuning of the drill. Fourthly, this technique is suitable only for partial restoration of the working capacity of a tool of a relatively small diameter (no more than 5).

Making a machine is not all. It needs to be positioned correctly in order to sharpen the drills as conveniently as possible. The place, the height of the installation is a personal matter of the master. But there is general requirement- exclude the slightest vibration of the equipment and ensure its leveling.

If the workbench in the garage is rather "flimsy", you will have to mount a special table on metal legs. A large corner, pipe or channel is suitable for this. The tabletop, taking into account the weight of the machine (primarily the engine), must be strong. Thin sheet metal is not an option. The machine stand can also be made of wood, but of sufficient thickness. Its attachment also requires attention. It should be as reliable as possible, at all points provided on the engine bed, and only on bolts.

When deciding on the circuit for turning on the engine, it is necessary to provide for the possibility of changing the number of revolutions. Since you will have to work with different drills, you need to know - the harder the material of the tool, the lower the angular speed of rotation of the abrasive wheel should be.

As practice shows, not all inexperienced craftsmen understand when a drill needs to be sharpened. Signs indicating that the instrument is dull:

• grinding (sometimes "humming") at the initial stage of drilling;
• rapid heating of the metal, often accompanied by a characteristic odor.

Failure to sharpen in time will significantly reduce the service life of the drill and is the most common reason its breakage.

Any cutting attachments for a drill become dull during operation, which, in fact, does not require proof. However, do not rush to throw them away, since you can restore the nozzle to its original performance by sharpening. Below we will explain in detail how to do this.

When is sharpening required?

If wood drills can be operated for a long time and at the same time remain sharp, then metal tools become unusable very quickly. Of course, experienced master detects a blunt drill by eye or by its first contact with the metal surface. If you are a beginner, you can determine the need for a tool for sharpening by the following criteria:

• in the process of drilling, there is a creak and whistle;
• the tool heats up much faster than usual;
• the quality of the hole is low - there are jags and burrs;
• chips come out of only one spiral groove (this sign may also indicate an incorrect sharpening).

Be aware that working with a blunt tip puts yourself in danger as it may break. In this case, flying parts of it can cause serious injury. In addition, the drill can "bite". In such a situation, if the drill is powerful or you are working on a machine, the part is pulled out of your hands, which often also ends in injury. Therefore, in no case should it be tightened with sharpening or changing the tip.

The main parameters of the part

So that you can sharpen the tip correctly, first of all, let's look at its main elements, which include:

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

During the operation of the nozzle, the cutting edge, bridge and back surfaces suffer the most. Therefore, the restoration of the tool occurs by sharpening the rear surfaces, to which we adjoin the cutting edge and the bridge. However, not everything is so simple: in order for the edge to become sharp again and a clear jumper to form, the sharpening angles must correspond to the values ​​from the table:

Compliance with these values ​​will allow the cutting edge to always be the first to come into contact with the surface of the workpiece, which will ensure maximum efficiency tool. The length of the cutting edge depends on the nose angle. Compliance with it will allow the chips to fit well into the groove and come out. If the angle is made sharper, the width of the cut strip will increase, as a result of which the chips will clog the groove and stop being removed from the hole with all the ensuing consequences. A too obtuse angle will reduce the efficiency of the drill.

We sharpen on a grinder

At home, it will not be difficult on an ordinary grinding machine... The only thing, it is desirable that the machine be equipped with a handyman, i.e. a small platform located in front of the working surface of the grinding wheel. The distance between the handcuff and the end of the circle should be no more than one millimeter.

The optimum speed of the grinding wheel is one and a half thousand revolutions per minute.

If the tip is very dull, i.e. cutting edges with rear surfaces have become asymmetrical, in order to properly sharpen the tool, it is advisable to make a simple device by following these steps:

• draw straight line on a handcuff at an angle of 60 degrees in relation to work surface abrasive disc. The line should be located opposite the work surface;
• fasten a piece of metal corner on the handy, aligning it along the marked line, as shown in the photo below. Those. the corner should also be located in relation to the working surface of the circle at an angle of 60 degrees. You can use a clamp to fix the corner. If you will be sharpening often, you can drill holes and fix the corner with bolts.

Thanks to this device, you can attach the drill bit to the back of the corner with your own hands and thus provide a back surface angle of 60 degrees. Now that everything is ready, you can get to work. First of all, you need to install the coarse abrasive disc and turn on the machine. Then you need to correctly pick up the drill. To do this, put two fingers of your right hand on the handcuff, and lay the tool to be sharpened on them. As a result, the fingers will serve as support. With your left hand, grip the shank of the tool to be sharpened. Turn the drill itself so that the cutting edge that you will sharpen is strictly horizontal.

Now attach the tool with the side plane to the back of the corner and bring it with your own hands to the working surface of the sharpener. Right hand should remain stationary, and the left, which holds the tool by the shank, should move slightly in the vertical plane, swinging the drill. Thus, the sharpening must be from the cutting edge to the end of the flank.

During the sharpening process, a large number of sparks, so be sure to wear safety glasses when performing this operation.

In this pattern, make several swinging movements with your left hand up / down. You don't need to strain your hands too much, as the drill will not vomit from you, so just be careful. Having sharpened one back surface, rotate the drill 180 degrees with your left hand and sharpen the second back surface in the same way. Upon completion of the work, make sure that the angle of the drill, i.e. the vertex angle is 120 degrees, which is optimal for metal tools. Also, make sure that the edges and rear backrests turned out to be symmetrical. If the tool is far from ideal, it still needs to be sharpened.

I must say that as a result of the movement of the shank in the vertical plane, the back surface is rounded. Therefore, such a sharpening is called conical. It is used for drills with a diameter of more than three millimeters. It is even easier to sharpen a thinner drill correctly for metal - its cutting part is pressed against the plane of the sharpener and sharpened without any swaying. As a result, the back surface acquires one flat plane. Therefore, such a sharpening is called single-plane. The grip of the drill with this processing is shown in the photo below.

After the sharpening is completed and the tool acquires the correct shape, you need to fine-tune it. The fact is that the surface after sharpening with a large abrasive is far from ideal. Therefore, you need to install a disc with a fine abrasive on the machine and remove all roughness. As a result, the surface should be perfectly smooth.

It is necessary to bring the sharpened tool to the working surface of the sharpener smoothly so that no impact occurs.

To make sure the job is done correctly, try drilling a hole, maybe not even deep, and make sure the edge is smooth and straight. This is the main indicator of a sharpened tool.

Drills for wood are also sharpened absolutely. The only thing is that their apex angle becomes sharper - 140 degrees. Accordingly, the tool is brought up to the sharpener at an angle of 70 degrees.

No grinding machine - grinder for all occasions

If you do not have a sharpening machine, but at the same time urgently needed to sharpen a drill, you can use a grinder (angle grinder). But keep in mind that the sander is one of the most dangerous handheld power tools. Violation of safety precautions when working with it leads to serious injury, and sometimes lethal outcome... Therefore, if you have no experience with angle grinders, it is better not to try to save money, but to buy new nozzle.

If you nevertheless decide to sharpen the drills with a grinder, use exclusively the end flap disc for these purposes. In addition, it is desirable that the grinder itself be small, i.e. low-power. The sharpening process is as follows:

1. 1. The grinder is placed on a horizontal plane with the disc upwards so that the disc is also located horizontally. The tool must be firmly held with the left hand, and the power button should also be controlled with the same hand.
2. 2. Then the drill must be brought to the disc and sharpened, trying to comply with the factory angles. In this case, the grinder should be turned on at minimum speed.

The disadvantage of this method is that sharpening is carried out "by eye", so if you did not sharpen metal drills before, it is better to refuse this method. Inexperienced actions can spoil the instrument even more.

Using adaptation - when theory is not needed

The easiest way to sharpen a drill for wood or metal, which does not require any skills and knowledge from you, is to use a special attachment for a drill or screwdriver. The device is a nozzle with holes of different diameters.

For sharpening, you need to put on a nozzle on the power tool, then insert the tool into the hole corresponding to its diameter and turn it until it stops. Special grooves will fix the drill in working position. Keep in mind that it is imperative that the drill is correctly positioned in the hole, as this will only cut the back surface at the correct angle. After installing the drill, you need to turn on the power tool and wait a while until one side of it is sharpened. Then the tool to be sharpened must be turned 180 degrees and the procedure repeated.

The disadvantage of the device is that there is a limitation in diameter. The minimum drill diameter that can be sharpened is 3–3.5 mm, and the maximum is 10 mm. Typically, the pitch is 5 mm. However, for domestic purposes, this is quite enough. The cost of such a device ranges from 600 to 4000 rubles, depending on the manufacturer. The most expensive are products from the German manufacturer Bosch.

A few words about the repair of concrete drills

All of the above sharpening methods apply to metal and wood tools. However, a drill with a Pobedit tip can also become dull. At the same time, it manifests itself in the same way as a tool for metal - it drills poorly, quickly overheats and emits an unpleasant high-frequency sound during operation. I must say that the principle of sharpening victorious drills is about the same as for metal tools, but there are some important nuances.

First of all, you need to measure the height of the cutting edge of a blunt tool. It makes sense to sharpen the drills if the height is at least 7-10 mm. If the height is less, achieve quality result will not work, therefore it is more profitable to purchase a new attachment. For sharpening, we need a diamond-coated wheel. Please be aware that the carbide tip will not tolerate high temperatures... Therefore, it is necessary to work at minimum speed.

To sharpen the carbide drill correctly, you first need to tweak the edges of the tip, which are the first to "lick off" when working on concrete. The corners of the soldering edges must be even, i.e. at 90 degrees. Then the rear surfaces are sharpened to the very soldering, as shown in the photo above. If carbide brazing grinded down to steel, it is necessary to sharpen the front part. Otherwise, mild steel will come to the surface of the cutting edge, and accordingly, no efficiency and quality of drilling can be achieved from the tool in this case.

In order to sharpen the victorious drill and at the same time not overheat it, use a coolant during work - water or machine oil.

As with any drill, be sure to keep it symmetrical. The cutting sides must be the same size. If the center of the axis is displaced, the efficiency of the tool will decrease, in addition, the holes will be uneven. There is also one more important rule- the harder the tip, the sharper the apex angle should be. For victorious tints, this angle should be 170 degrees.

That, in fact, is all you need to know for self-sharpening drills.

How to make a drill sharpener. Tool for manual sharpening twist drills. Some time ago, I accidentally stumbled upon (meaning the author of the article, see the source) on the network very useful video tutorials by V. Leontyev on manual sharpening of spiral drills:

But then an idea arose of how to make sharpening drills even simpler and more convenient. As a result of thoughts and experiments, the device described below appeared. First, it was necessary to modernize - to bring to mind the existing factory-Chinese (such as German) winepress. Because it was almost impossible to work with him using the techniques of V. Leontiev.

Factory-made electric grinder.

Flimsy standard support arm.

Unsuitable for work construction of the hand-hand.

Firstly, the bracket for attaching the handler to the disc casing is too flimsy, made of metal 2 mm thick. Bends with a little effort. Therefore, naturally, the sharpening angles are +/- kilometer! And the shape of the handguard absolutely does not allow making a normal clearance angle according to the method of V. Leontiev, since the drill when lowering the shank rests against the corner of the bracket. Moreover, the handcuff itself is installed BELOW the disc axis. That is, there is no way to get a normal clearance angle at all, unless you use the end surface of the disc.

The plane of the pad of the handguard is much lower than the axis of rotation of the disc.

New bracket for attaching the handyman.

For the normal bracket, a piece of metal with a thickness of 4 mm was used, bigger size and additional mounting screws. The old bracket was attached to two rivets, which had to be cut off. The new bracket is now much stiffer than before. Also, from pieces of a corner and a strip, a horizontal shelf of a handrail was welded with additional mounting holes. Its position can be adjusted within certain limits.

Comparison of the thickness of the metal in the new and old handcuffs.

The new bracket is fixed at 5 points.

Fixture details. Bracket. Assistant. Swivel plate ...

Further, the device itself was made directly. It is a swivel plate with a welded bushing that can swing on an axle fixed in an eyelet, which in turn is attached to a handrail. Attached to the top of the swivel plate is a drill guide plate in which a triangular groove is selected.

Assembled fixture. The plate is in a horizontal position.

Assembled fixture.

Sharpening device.

At first, instead of this plate, a guide was tested in the form of a piece of a corner (as in the video by V. Leontiev), but this option is not at all suitable - the drill is difficult to fix normally (it tries to escape to the right when it touches the disc), especially since it is also required feed forward when forming a back corner. In general, the corner (it is in the photo) is completely unsuitable.

The device is in the lower position.

Working with the device resembles the movements of the author of video tutorials, only instead of a finger and an eye gauge, the swing axis and the set angle of sharpening of the drill are used. It is much more convenient with the device to control the parallelism of the cutting edge of the drill to be machined. You just need to turn the insert down and press the drill into the groove so that the line of the cutting edge is parallel to the plane of the insert - the swing axis of the insert. This moment is shown in the photo.

Installing the drill on the hand-hand to the grindstone.

First, the edge itself is formed. When machining a clearance corner, it is necessary to lower the plate down at the same time and feed the drill itself forward towards the disc. It is necessary to try not to allow the drill to rotate around its axis when forming the edge and processing the clearance corner. I control the symmetry of the edges in the same way as in the video tutorials. By the way, instead of a swinging plate, you can install a piece of a corner with fixed angles - sharpening and rear - this is for sharpening carbide drills on the handlebar. It is only necessary to locally determine the required length of the sides of the corner to obtain the desired rear sharpening angle, since it also depends on the diameter of the disc and the location of the handguard relative to the axis of rotation of the disc.

Installing the drill into the guide groove of the plate.

Drill setting control. The cutting edge of the drill is parallel to the insert surface.

Guide groove configuration.

Tool for manual sharpening of twist drills.