To keep drills sharp - how to make a sharpening machine with your own hands. Devices for sharpening drills for metal Devices for sharpening drills from files

One of the main parameters of a twist drill is the tip angle, which for durable metals (steel, cast iron, hard bronze, titanium, etc.) is approximately 120 degrees.
Deviation of this angle more or less from the nominal value makes it difficult for the drill to operate effectively. In the first case, productivity drops and the tool overheats; in the second, the drill may simply break, unable to withstand the excessive load.
To maintain sharpening parameters without special devices, you must have high qualifications and experience as a tool sharpener. Well, it will be almost impossible for a non-specialist, especially in domestic conditions, to do this.
But, having some tools and simple materials, you can make a not very complicated, but reliable device for sharpening the corner at the tip of a twist drill for hard metal.

What you might need to work on the device

To do this you will need the following tools:

calipers;
marker;
metal vice;
Bulgarian;
pliers;
welding machine;
sharpening machine with an emery wheel.

Materials you need to have on hand for work:

regular hex nut;
castle nut;
bolt of the same size and thread as the nuts;
twist drill that requires sharpening.

Manufacturing process

The peculiarity of a hex nut is that any two adjacent faces meet at an angle of 120 degrees. The apex angle of a twist drill for working on hard metals is approximately the same size. This random coincidence can be used to make a tool for sharpening a twist drill.

To do this, using a caliper and a marker on the nut, mark the cutting lines to create a triangular slot, symmetrical with respect to the diagonal connecting two opposite corners of the nut. The drill will be placed longitudinally into it before the sharpening process.

To cut out the intended triangular groove in the nut, it is clamped in a vice and, using a grinder, cuts are made along pre-drawn lines. You can use pliers to remove sawed off pieces of the nut.

Next, take a castle nut and weld it with its base to the first nut on the side of the cut groove. Moreover, it is necessary to maintain their absolute alignment, because when small-diameter drills are sharpened, the bolt, having passed through the castle nut, will begin to screw into the lower nut in order to firmly clamp the drill in its groove.

Now we screw the corresponding bolt into the castle nut, which will securely press the drill placed in the sharpening groove on the sandpaper of the sharpening machine.

All that remains is to sharpen the drill on an emery wheel, using the edges of the bottom nut as a template.

To do this, we simply grind the protruding part of the drill flush with the edges of the nut, which even a first-year vocational school student can easily cope with.

After sharpening is completed, the bolt is loosened, the drill is removed from the homemade device and can be used for its intended purpose.

Additions and improvements

During the welding process of nuts, liquid metal may splash onto the threads of castle and regular nuts. To eliminate this nuisance, it is necessary to screw a bolt into them and thereby protect the thread.
Since it will not be possible to cover all the diameters of drills with one device, at least two template clamps will be required: one for small drills, the other for large products. Accordingly, in the first case the nuts will be small in size, and in the second - large.

Having picked up correct drawing devices for drill sharpening, you can make homemade full-fledged equipment at home. Thanks to this device, the task of providing the required geometric shape tool.

When using it, there is no need to worry not only about the rotation of potentially dangerous sharpening stones, but also about the sharpening angles, which must be maintained correctly, catching every degree by hand.

Features of using homemade sharpening devices

During the process of drilling holes in metal products, drills wear out quite a lot, which leads to their heating and loss of their properties. To avoid this phenomenon, measures are required to ensure regular restoration of their geometric parameters. This can be done using special equipment for sharpening drilling tools. The creation of such a simple device can be done independently, which will allow for high-quality sharpening without any significant financial costs.

Many experienced professionals practically do not use sharpening devices, since they are absolutely confident in their experience and eye, which allows them to sharpen drills correctly. But in practice, the use of such devices is extremely necessary, as this allows mechanization of this process. As a result of such work, maximum accuracy and quality of sharpening will be ensured.

The modern market offers different kinds equipment that allows high-quality restoration of the geometry of cutting tools, even in the absence of experience in this matter. At the same time, there is no urgent need to purchase such products, since they can be made with your own hands according to the existing drawings of devices for sharpening drills.

Drawings of simple devices

The simplest devices for sharpening can be bushings, the internal diameter of which corresponds to the transverse dimensions of the drills. The sleeve is rigidly fixed into a reliable base, taking into account a certain angle. When selecting a bushing for such devices, you should pay attention to the correspondence of its internal diameter with the transverse size of the tools being sharpened. It is prohibited for the tools being processed to dangle in the sleeve, since even with a deviation of 1-2 degrees along the axis from the required values, the quality and accuracy of sharpening can significantly decrease.

Such homemade devices To sharpen drills, they must be equipped with clips. Copper or aluminum tubes with an internal diameter equal to standard size drilling tool used.

In some cases, the task can be simplified by setting this design wooden block, in which holes must be drilled with a diameter corresponding to the tool used. One of essential elements Such a product is considered to have a tool rest, which is necessary for:

ensuring correct fixation of the drilling tool and the ability to move accurately in relation to the surface abrasive stone;
creating a stop point for the drill being sharpened.

Such products made from oak bars, which have holes of different sizes, are the most reliable. Thanks to them, high-quality and precise sharpening of tools is performed. The main task that must be solved by a homemade machine or similar device is the correct orientation of the cutting part of the tools being processed to obtain the accuracy of the required sharpening angle.

For the manufacture of homemade machine For sharpening drills, a number of different design variations of such equipment can be used. If you have the appropriate drawings and understand the operating principle of this equipment, you can make sharpening equipment yourself at home.

The structure consists of the following elements:

Promopore site

Holder for drill and stop screw

Bolts, nuts, pins, screws

Exist important rules that must be observed during the operation of such a device, namely, the tool being sharpened should not rotate around its axis. In case of even a slight rotation, sharpening must be done again.

The sharpened tool must be cooled in a natural way. After which you should check its restored geometric parameters. You can use a template for this. It should be taken into account that each cutting edge of the drill may differ from each other by no more than a tenth of a mm. Wherein, Special attention It is worth paying attention to this parameter if the drills have a small diameter.

Video “Device for sharpening drills according to drawing”

Drawing of a full-fledged device

A fairly simple way to make homemade sharpening equipment, which is practically no different from the factory product. To assemble it according to ready-made drawings it takes about 1.5-2 hours.

To make a device for sharpening drills with your own hands, you must provide the following: Supplies, equipment and tools:

welding machine;
electric drill;
Bulgarians;
standard locksmith tool kit;
a corner, the size of the shelves is 30x30, and its length is 100-150 mm;
metal plates of different thicknesses (3-5 mm);
pins or a piece of steel rods, the diameter of which is 10-12 mm;
washers, screws, bolts and nuts of various sizes.

First of all, the manufacturing of the bed is carried out, which will be the base in the sharpening device. To do this, use a steel plate onto which a steel rod (12 mm in diameter) is welded at an angle of 75 degrees. It will be the axis.

After that, a washer should be placed on the welded rod, which will act as a support bearing. The amount of angle and rotation of the bed when sharpening the drill will be insignificant, so there is no reason to use a standard ball bearing.

The bed where the sharpened tool will be placed is made from a prepared corner. The one side on the corner profile that faces the whetstone side needs to be ground at a 60 degree angle. On the stock, according to the drawing, a bracket is welded, through which the rotating unit of the device will be fixed. As a result, a structure will be made, the corners of which, in the case of a parallel position of the bed and frame, should be located to the surface of the abrasive stone in accordance with the angle of the drill being sharpened.

The sharpening machine, which is shown in the drawing, has fixed tilt angles, but for greater possibilities it is desirable to provide the ability to adjust the angles. In such cases, there will be a greater chance of using the device if it is necessary to restore tools with different sharpening angles, for example, if it is necessary to sharpen drills for metal, concrete, etc.

To create a more functional unit, you can use drawings of other designs that can adjust the angles:

Video “Device made according to drawing”

A device for sharpening drills is useful in any household. After all, working with a dull drill is a pain. You can make the mechanism yourself using unnecessary and outdated parts.

Rules for sharpening drills

Drills can be sharpened on special sharpening discs, manually or on machines. Before starting work, carefully examine the drills: if there are serious defects on the surface, you need to start sharpening with a coarser abrasive. If the tool is a little dull, use a finishing disc.

When sharpening manually with your own hands, you need to follow the rules:

hold the shank with one hand and adjust the working end with the other;
process the cutting edge with the side of the sharpening disc;
First, one side is sharpened, after which the drill is carefully turned over and the second is processed.

During processing, it is important to maintain the original shape of the drill and the direction of the cutting edges. It is necessary to ensure that the point of the tip does not move from the center, otherwise the tool will deviate to the side during operation. If after sharpening the angle of the cutting edges is not the same, the work of the drill will be poor. This is determined using a template made by yourself or by eye: the shape of the tip should be a cone. To avoid errors, it is better to edit on specialized devices.

Types of sharpening equipment

A homemade device is designed for sharpening drills made of various metals, cutters, taps, milling cutters, countersinks, cutters.

Equipment can be:

specialized - processes a single type of tool;
universal - used for all types of cutters and drills.

Homemade mechanisms often belong to the universal household type. Industrial machines are powerful and work with large tools. There is no need for such at home; they are noisy, take up a lot of space and are energy-consuming.

Household ones are suitable for sharpening drills of small and medium diameter; they are compact and economical.

Making a sharpening machine

To assemble the machine with your own hands, you need to prepare:

electric motor;
grinding disc;
toggle switch;
stand;
electrical cable;
stub.

All components of the machine are placed inside the body with your own hands. This will make work safe and convenient. Only the motor pulley on which the grinding disc is mounted should be accessible. The machine is permanently attached to the workbench, so the location must be selected in advance.

place the electric motor in Right place, mark the attachment points on the table;
drill holes for the mounting bolts;
return the electric motor to its place and screw it to the workbench; clamps made of thin metal strips are suitable for fastening;
install the protective housing;
Place a grinding wheel on the engine pulley.

It is advisable to select an engine with an extended pulley, otherwise it will have to be delivered. First, put on the washer, then the circle. If the diameters of the pulley and disk do not match, an adapter sleeve is used. A threaded hole is made on the side of the bushing, and an additional fastening bolt is screwed into it.

In terms of power for a homemade machine, an engine from washing machine. Do not select a high-speed engine, as sharpening of drills occurs at low speed.

Now you can connect the electrical component: toggle switch, motor and connect them to the outlet.

Additional devices

Handmade additional accessories will make the work of sharpening drills more convenient and accurate.

Template for verification. The template is cut out of a sheet of thin (1 mm) soft metal (aluminum, copper). The template reveals the angles at the tip, the length of the working edges, the angle between the working edge and the bridge. Since it is almost impossible to check the rear sharpening angle of a drill using a template, the sharpening angle is checked. The template is cut out before using the drill for the first time.

Guide. This is a small attachment that is made of a metal strip and is fixed to the body with a bolt. During operation, the drill is placed on a guide and brought to the grindstone.

Goniometer. On the stand, which is described above, divisions of sharpening angles are applied. You can cut off a piece of metal protractor with corner marks and attach it to a stand. You need to cut off a part with angles of more than 30 degrees, since smaller ones are not used when sharpening.

A device that makes drill sharpening easier. It consists of a fixed frame and holder, in which holes are provided for inserting cutters different sizes. The holder can be removed. The bed is made of a 50 mm board, a rail is attached to it at an angle of 32 degrees. The rack positions the holder with the tool at the required angle. The holder is cut out with your own hands from a block, the surface of which is removed at an angle of 65 degrees. The beveled part is laid against the rail. The bevel angles of the holder and the rack depend on the type of sharpening.

Multifunctional mechanism

Sharpening drills will become easier when using this mechanism. The device consists of:

roller slides;
guide;
shaft;
protractor;
drill chuck.

The guide should be made wide enough, and a protractor is attached to it. The rotation axis is a bolt inserted into the provided hole. Guides and a movable plate are placed on the rotating part. An axis and tube are fixed on its surface; on one side the axis ends with a drill chuck, on the other - with a handle. The movement of the thrust plate is ensured by a threaded axis.

At the bottom of the thrust plate there is a limiter (also known as a pointer), which simultaneously indicates the required displacement angle and fixes it in the desired position.

The mechanism works as follows:

the drill is fixed in the chuck;
the thrust plate is locked at the required angle;
the tool is rotated along the longitudinal axis using a handle;
mark the angle;
turn the cutter 90 degrees and process the second half, reaching the marked angle.

Rules for sharpening on a homemade machine

When machining drills, both hangers must be identical. This means that the drill will fit smoothly into the hole and perform drilling efficiently.
Before starting the machine with your own hands, securely attach the grinding wheel to the pulley.
Carry out initial processing with a disc with a coarse abrasive. When you notice a burr on the drill, the disc should be replaced with a thinner one.
While sharpening, maintain the required angle at all times.
The circle should only rotate in one direction, along the blade.
Do not allow the cutter to overheat; it should be cooled periodically during processing. Do not immerse overheated tools in cold water, this promotes cracking of the metal.

Several options for sharpening drills in the videos.

You can easily make a device for sharpening a drill for metal with your own hands. This will require a little time and a few basic elements for the future design.

Devices used for sharpening drills for metal, wood, plastic and other materials are divided into two types:

Specialized. They can only sharpen one specific type cutting tool;
Universal. With their help, all kinds of cutters, drills for metal, wood, etc. can be sharpened.

If we are talking about making a device with our own hands, craftsmen usually try to make a universal model. The device is easy to use and effective for sharpening drills of small and medium diameter. Ideal for household purposes.

Elements of the device

To make a sharpening device, you will need some elements and tools:

Stand;
Toggle switches for turning the sharpener on/off;
Disc for grinder;
Electric motor;
Electrical cable to connect the device to the network;
Plugs;
Case material.

All the components of your drill sharpening machine will be located inside the body. This way you can increase your own safety when working with sharpening equipment.

When assembling the structure, leave the pulley from the electric motor accessible, since the sharpening disc is placed on it. It is advisable to first select a stationary location for the machine, since it should be fixed on a workbench or desktop.

The process of assembling the sharpening device itself is as follows.

Install the electric motor in a pre-selected location.
On the table where the device for turning metal drills will be located, mark the fasteners.
Using an electric drill, make holes according to the markings for the mounting bolts.
Secure the electric motor with metal clamps in its rightful place.
Fix the casing, which will act as protection.
Install a grinding disc on the electric motor pulley.
The engine itself should have an extended pulley, as this will be more convenient when operating the sharpening device. Don't forget to put a washer on the pulley before installing the circle.
If the diameter of the pulley and the circle do not match, you can use an adapter sleeve. A threaded hole is drilled on the side of the bushing, onto which an auxiliary fastening bolt is then mounted.
There is no need to choose an engine that is too powerful. High speeds will only harm your metal drills. Most craftsmen adapt an engine removed from old washing machines to a grinding unit.
After completing the assembly, connect the toggle switches, connect the motor and all electrics via cable to the outlet.

Assistive devices

If you managed to assemble with your own hands a fairly useful sharpening device for various drills for metal, wood or plastic, we advise you not to stop there.

There are a few additional elements, equipping the sharpening device with which you will significantly expand its functionality and increase your level of comfort when working on drills.

Test template. To determine correct angles When sharpening a drill, you will need a special table or template. The template will always be at hand. With its help, you will determine how correctly the sharpening angles are made, what is the duration of the working edges, and what are the angles between the bridges and the working edges. Templates are made from thin, soft metal on the base of a new drill before its first use;
Guides. A kind of small attachments made from metal strips. They are bolted to the body of the sharpening device. When working, you will need to place the drill on these guides, gradually bringing the tool to be sharpened to the abrasive stone;
Goniometers. The easiest option is to take a regular metal protractor, cut off part of the device and attach it to a stand. Cut off the part of the protractor where the scale is more than 30 degrees. This is due to the fact that drills are not sharpened at a smaller angle.

Multitasking device

If you make such a device, the accuracy and convenience of sharpening metal drills will increase significantly. At the same time, assembling the structure is quite simple. To make the mechanism, arm yourself with the following components:

Roller slides;
Guides;
Shaft;
Protractor;
Drill chuck.

It is recommended to make the guide wide and attach a protractor to it.
The role of the rotary axis will be a bolt, which is inserted into a pre-calibrated hole.
On the rotating part there is a guide and a movable metal plate.
An axis and tube are mounted on the surface of the plate.
One end of the axle is used to install the drill chuck, and the other is used under the handle.
The thrust plate will move due to the threaded axis.
At the bottom of the plate there is a limiter. It performs two functions at the same time - it fixes the mechanism in the required position and indicates the desired angle.

The device operation process looks like this:

The cutting drill is installed in the chuck;
The plate is fixed in the required position to create a sharpening angle;
The device rotates along the longitudinal axis with a handle;
The angle is marked;
The cutter is turned 90 degrees, after which the second half of the metal drill is processed with your own hands.

Operating rules

Because the we're talking about When working with a homemade drill sharpener, you must follow some rules. They will protect you from injury and also allow you to sharpen the drills correctly.

When sharpening drills, make sure that the hangers are the same. This will ensure that the drill fits neatly and evenly into the device and, after sharpening, will be able to drill holes efficiently.
Before starting the machine, make sure that the sharpening disc is firmly secured to the electric motor pulley.
The first stage of drill sharpening is performed with a coarse abrasive sharpening disc. When burrs begin to appear on the metal drill, change the sharpening disc to a more delicate one to complete the sharpening.
When sharpening with your own hands, strictly adhere to the specified angle.
The rotation of the grinding wheel must be carried out strictly in the direction along the blade. If you move in the opposite direction, you will not be able to complete the job properly.
Make sure that the drill does not overheat while sharpening. Stop periodically and let the metal drill cool down. But under no circumstances should you cool it by immersing it in cold water, as this will cause the metal to lose its strength.

Watch visual videos about assembling sharpening devices. Be sure to take into account the diameter of the cutters that you will sharpen on the machine, so that the assembled mechanism will provide high-quality and efficient processing products.

Technological process machining materials includes many different operations, which require high-quality and sharp tools. Thus, in a machine shop at any machine-building enterprise, a set of turning, milling, drilling and more complex machines can be used. They use their own type of tool, each of which has a specific sharpening method.

Features of drills

Mechanical processing of metal is associated with huge loads on the instrument. In general, it consists of three main parts: connecting, body and cutting. So the cutting part is a small wedge-shaped element designed to penetrate the metal and remove part of it from the workpiece.

If, for example, in a turning tool or a disk cutter everything is clear with the shape and design of the cutting part, then when processing holes on a drilling machine everything is much more interesting and complicated, so you need to know how to sharpen the drill correctly. This is a tool designed for axial metal processing. That is, the feed movement is directed strictly along the axis. This should be taken into account before sharpening a drill for metal, because an incorrect cutting angle will lead to vibration and breakage.

Main elements of the cutting part of the drill

Before sharpening a drill for metal, you should familiarize yourself with the design of its cutting part, which includes the following elements:

1. Main cutting edge.

2. Auxiliary helical cutting edge (ribbon).

3. Jumper.

4. Front surface.

5. Back surface.

What will you need for sharpening?

At the enterprise, everything necessary for instrument restoration is always at hand. And here home handyman we have to look for an alternative to high-quality factory devices in more simple solutions, which can be used in a regular garage. And yet, before sharpening a drill for metal, stock up on the minimum set:

1. Grinding wheel. It must be installed on a rotating shaft. The device is popularly known as “emery”. It is very common in the garage.

2. Coolant container.

3. Coolant (water or engine oil).

In order to maintain the sharpening angle of the drill, such a set may not be enough. After all, you will have to control the process “by eye,” which is unlikely to happen without some experience. In this case, the basic kit must also include a device for sharpening the drill, which you can buy or make yourself.

Controlled parameters

When everything is ready, you need to familiarize yourself with some theory in order to have an idea of the basic parameters of an axial cutting tool. Before you sharpen a drill correctly, you need to know its angles:

1. Front. Defined in the main cutting plane (runs perpendicular to the main cutting edge) as the angle between the rake surface and the main plane (perpendicular to the cutting speed vector). It is directed tangentially to the drill circumference.

2. Rear. Also defined in the main cutting plane as the angle between the flank surface and the cutting plane (passes through the velocity vector and the cutting edge).

3. Apex angle located between the two main cutting edges when looking at the drill from the side.

The optimal value of the front angle is 18-20 degrees, the rear angle is 10-12. The tip angle in metal drills has a standard value of 118 degrees.

Sharpening process

Now let's talk about how to sharpen a metal drill using regular sandpaper. The main sharpening of this axial tool is carried out along the rear surface. To do this, turn on the emery, firmly grasp the drill in your hand so that the main cutting edge is directed towards the rotation of the sharpener. Now we bring the edge to the sharpener, after which we turn the drill by the shank so that the cutting edge is parallel to the surface of the circle. We perform the same operation with the second cutting edge. The result is the so-called simple sharpening drill, which is optimal for most metal processing modes.

Simple sharpening is used for drill diameter up to 10 mm. By increasing this parameter, you can additionally sharpen the front surface. As a result, the rake angle decreases, which means the thickness of the blade increases (the so-called angle cutting edge) and, accordingly, the service life of the drill.

Sharpening using a jig or machine

The method described above can be called artisanal, since precise control of the drill parameters directly during sharpening is simply impossible to achieve. IN best case scenario you will check the angles after finishing sharpening, and in the worst case, just check how much better the drill has become. How to sharpen a drill correctly?

Of course, for this it is better to use more advanced options that will allow you to adjust to certain angles in advance. In this case, you will need a device or machine for sharpening drills.

If the scale of work in your workshop is large enough and tool sharpening is required constantly, then purchasing a machine would be optimal. It will significantly simplify the process, especially if you need to resharpen carbide drills for metal. The main advantage of its use is the exact adherence to predetermined parameters. When there is a large volume of work, it is unacceptable to use an incorrectly sharpened tool, as this will lead to a decrease in productivity. Modern sharpening machines allow you to receive Various types drill sharpening:

1. X-type. Mainly used for drilling blind holes. Designed to reduce axial cutting force.

2. XR type. Used for universal drills. The penetration into the material is somewhat worse than in the first type, however, such drills have increased strength and durability.

3. S-type. The point described above is used here, which also allows you to increase the service life of the drill during processing various materials(from cast iron to stainless steel).

4. N-type. A point is also used, but of a smaller size. Drills with this sharpening are used for deep drilling.

Device design

As has already become clear, manual sharpening drills are the work of a professional who not only knows the correct angles, but also feels the cutting process. Unfortunately, such an instinct comes only after many years of practice working with a drill press or drill. There is no need to experiment, as you can make it yourself or purchase a sharpening device. In both cases it will include the same structural elements and work according to the same principle.

So, the main task of the device is the correct orientation of the drill relative to the plane grinding wheel. To do this, its design includes a base plate, on which it is desirable to place both the device itself and the electric motor on the shaft of which the sharpener is located. The plate also contains a rotating column on which the drill is fixed. It must be able to not only rotate, but also move towards the grinding wheel.

Any bearing assembly with a shaft can be used as a column, for example from old drill. A drill bed is fitted onto the shaft rings (you can use an adapter sleeve), to which it is pressed with screws. After fixing the drill, the sharpener drive is turned on, the column is brought to the grinding surface and rotated to give the back surface of the drill the correct shape. It is important that when initially setting up the device, the drill tip angle is maintained at 118 degrees.

Sharpening with attachments

Another simple one convenient way involves the use of a device such as a drill sharpening attachment. Its main advantage is its versatility and ease of use. The device has a cylindrical shape. On one side there is a connecting unit, through which the attachment is installed on the drill spindle. On the other side there are holes for installing drills of a certain diameter. To sharpen, the drill is inserted into the hole, after which the sharpening mechanism is driven by the drill motor.

Security measures

Drill sharpening is associated with the formation of small particles that come off the sharpener during wear. They heat up and fly apart different sides in the form of fiery sparks, so for safety you should use safety glasses and gloves.

When sharpening a drill without a jig, make sure to securely fix its position. Otherwise, upon contact with the sharpener, it may simply be torn out of your hands.