How to properly sharpen a drill at home

How to sharpen a pobedit drill at home - Machine tools, welding, metalworking

Sharpening metal tools allows you to fully restore their functionality. The operation can be performed using various auxiliary devices.

How to properly sharpen a drill for metal and not spoil the cutting surface of the product will be discussed in the publication.

Signs of dull metal drills

Sharpening should be started only when obvious signs of dullness of the cutting edge are detected.

Among the main manifestations of the disease are the following:

• increased noise during operation;
• metal shavings have a fine fraction;
• tool overheating.

When drilling metal with a dull drill, a high-frequency sound occurs from the friction of the working edge against the workpiece. Therefore, if increased noise occurs, you should postpone work and start sharpening. If you continue drilling into metal, the cutting product will heat up to too high a temperature due to excessive heat.

Before the above-described signs appear, a decrease in the sharpness of the drill may be indicated by the absence of spiral chips. Such a sign cannot always be detected in time. If the drill, when fed correctly, produces too small chips during operation, it is recommended to immediately begin debugging the tool.

How to sharpen a drill for metal

A correctly selected device will significantly reduce time costs and perform the job as accurately as possible. Find out below how to sharpen a metal drill using a sharpener.

In addition to the main unit with an electric motor and a wheel, you will need to purchase special devices that hold the drill in a stationary state. Such stands allow you to control the angle of inclination and feed of the tool during turning.

Many devices allow you to debug metal cutting products with a diameter of 3 to 19 mm. To turn twist drills, you can use special machines that have a built-in electric motor and a feed mechanism.

Unlike using a conventional sharpener and holder, professional equipment can cost tens of thousands of rubles. Therefore, if sharpening drills is not a profession, then you can get by using the above-described tandem of a sharpening wheel and a holder, or straighten the tool manually.

You can sharpen a drill with a file without experience. The main thing is to choose the right file. Considering the fact that even cheap drills are made of high-quality cutting steel, you will need to select a diamond-coated needle file. In addition to the file, you need to prepare a vice in which to fix the tool.

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In order not to waste time and energy on the manual method, you can use a grinder with an abrasive wheel.

Sharpening a drill with a grinder

Almost every home workshop has a grinding machine, so the method will be one of the most budget-friendly.

In addition to the grinder with the grinding wheel installed, you need to prepare a vice in which to hold the drill during sharpening. The room where the tool is being adjusted should be light so that the process of removing metal from the cutting surface can be controlled.

Debugging is carried out in the following sequence:

• the drill is installed in a vice in a vertical position;
• a grinder is used to remove part of the trailing edge to completely eliminate signs of wear;
• The cutting edge is sharpened at an angle of 120 degrees.

To prevent the drill from overheating during the turning process, the contact of the emery wheel with the metal should last no more than 2 seconds. By repeatedly removing a small amount of metal from the working edge, it is possible to adjust the tool to the required angle.

For measurements, it is recommended to make a template from plastic that will help control the sharpening angle.

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It is more convenient and safer to carry out work using a grinding wheel and a special holding device.

Sharpening a drill with a sharpener

Determining the amount of damage to a cutting product and debugging by eye is possible after many years of practice.

In other cases, you can install a special drill holder in close proximity to the emery wheel. The fastening must be strong so that the clamp does not move during work. If the sharpener is fixed to a wooden base, installation of the clamp must still be done using a bolted connection.

To perform sharpening: the tool is securely fixed in the holding device, the sharpener motor is turned on and the drill comes into contact for a short time with the grinding wheel at a pre-selected angle.

1. If nicks have formed on the surface of the cutting product, then before debugging it, it is necessary to remove the damage evenly on both sides.
2. Caution should be exercised. Products of large diameter are heated from contact with the abrasive wheel to high temperatures, which leads to a decrease in the mechanical strength of the metal.

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Sharpening using a drill attachment

Without an emery machine, using a special attachment for a drill, you can perform the operation efficiently and with less time.

You can purchase the attachment at any specialized store, but the device can only be used for sharpening medium-diameter products. Most of these attachments allow you to effectively turn tools with a diameter of 4 to 10 mm.

For beginners, the method is the most preferable. Drill sharpening is performed as follows.

• install the attachment on the drill;
• the drill is inserted into a hole of a suitable diameter;
• the drill is turned on and the product is sharpened on one side;
• By turning the drill 180 degrees, the opposite edge is sharpened.

To use the device effectively, consider the following features:

1. Only slightly dull tools can be sharpened using a drill attachment. If there is deep damage to the cutting surface and the drill is overheated, it will not be possible to restore the product.
2. The sharpening angle in such devices is fixed. Therefore, to restore drills for working with non-ferrous metals, you will need to purchase an original device, or modify the products with a file.

Despite some disadvantages of this design, its use simplifies and speeds up the process of restoring cutting edges, and its low cost explains its popularity.

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How to sharpen small items

Unfortunately, it is unlikely to be possible to sharpen a thin drill using mechanized methods, including drill attachments. All work to restore a small-diameter product will need to be done manually.

The first attempt may fail, so you should first select an inexpensive thin drill that needs restoration and perform the operation on it. To work, you will also need a small diamond file and glasses with 4x magnification.

The process occurs in the following sequence:

• the drill is ground down to about 1 mm;
• The file is used to consistently sharpen the edges of the tool to the required angle.

The entire operation is performed “by eye”; it is important to use magnifying glasses and a powerful lighting device when working.

If your first attempt is unsuccessful, you should know that any skill can only be developed over a certain period of time. If you fail, don’t give up trying to learn a useful skill, like sharpening thin drills with your own hands.

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Sharpening products of other designs

In addition to twist drills, tools of other designs are used for metal processing. You can debug the following tools at home.

Cone gimlets

You can sharpen a step drill using a regular file. The cutting edge of the product is sharpened at a right angle.

If a cone drill becomes dull in a limited area, then sharpening should be done without going beyond the damaged area.

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Crowned

When debugging hole saws, a special device is used and you need to know at what angle the metal should be removed from the cutting surface. Considering all the difficulties and time spent on performing the procedure, it is better to turn to experienced craftsmen for sharpening.

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Conclusion

It’s not difficult to learn how to sharpen metal drills yourself.

1. For small volumes, it is enough to purchase a high-quality file and carry out the process manually.
2. For large volumes, to reduce time costs, it is better to purchase special equipment that will speed up the work and reduce the likelihood of incorrect dressing of the tool.

(15,00 out of 5)

Source: https://stanki-info.com/kak-zatochit-pobeditovoe-sverlo-v-domashnih-usloviyah/

Sharpening a drill for metal

Surely you tried to sharpen a drill with your own hands. Did not work out. Well, let's look at this problem. First, a little theory and terminology. Then we will get acquainted with the tools and technology. Including a budget drill sharpening kit. Let's begin.

1. What kind of drills are there?

The geometry of this tool is very diverse. We will only consider shapes that are typical from a sharpening point of view.

• Cylindrical spiral.

The most common drill. Usually it has 2 chip removal grooves, but there are more.

• Stepped.

Convenient to use when holes are drilled in sheet metal and of different diameters.

• Metal crown.

Used for drilling large diameter holes in sheet metal.

2. Drill material

Let's consider the materials in order of increasing wear resistance and price:

• Conventional drill made of cutting steel without additional processing. The cheapest. The color of ordinary steel.• Treated with superheated steam. It has a black color.• Tempered ones have a faint golden tint.• When coated with titanium nitride they have a bright golden color.

• Cobalt alloyed ones are characterized by the presence of a golden-red hue.

3. Drill elements for sharpening

For a better understanding, we will consider sharpening elements using the example of a two-flute cylindrical twist drill.

• Cutting edges cut metal from the hole area.• Flank surfaces. It is they that are processed when sharpening a drill, to give the cutting edge sharpness and the desired geometric shape.• The jumper will be the first indicator of the correct sharpening of the drill.

It is these elements that you should concentrate on when sharpening a drill.

4. Device for sharpening drills in a workshop

Here we will look at a device for sharpening drills with tools that are often used at home.

4.1. Grinding machine (grinder)

To obtain acceptable sharpening quality, it is necessary to secure the power tool.
If you have an assistant, everything is solved quite simply. Have an assistant place the electric machine on a hard, level, horizontal surface with the disc facing down and the shield facing up. For example, on the table. The grinder should rest on the disc guard. And, holding the body, in the places indicated in the photo, it will securely fix it.

If you do not have an assistant and suitable holders, you can use a common bench or carpenter's vice. Fix the angle grinder so that the jaws of the vice do not cover the ventilation holes. The abrasive disc can be oriented either vertically or horizontally.

You can use a regular (cutting) disc, but it is better to use a special one – a sharpening one. It is much thicker than the cutting one.

4.2. Hand drill

For attaching a drill, everything you read about attaching an angle grinder in the previous paragraph is true.

IMPORTANT! Only a drill with a jaw chuck is suitable for sharpening.

Not everyone knows, but there are holders for grinder discs on sale that allow you to use “grinder” cutting and sharpening discs with a drill. This is how a high-speed drill can replace the functions of an angle grinder.

You can also use a sanding disc with sandpaper glued to it. The harder the base on which the paper is glued, the better. Nowadays you can find sandpaper that does not stick to the disc, but sits on Velcro. This one is also good. In this case, the quality of sharpening will be worse.

Instead of a drill, a grinder disc holder or a grinding disc is installed in the drill chuck.

4.3. Roughing and sharpening machine (sharpener, emery)

Not every home has a similar unit. But we will still take a brief look. Since it is easiest to understand the technology for properly sharpening a drill and how to properly adapt a home tool for sharpening.

An abrasive wheel made of electrocorundum is designed for processing steel, including sharpening drills.

Horizontally, at the level of the axis of rotation of the abrasive wheel, there is a support - a steel strip. Serves as a support for fingers and tools when sharpening.

5.1. Preparation for sharpening

Using a marker, draw a line on the surface of the tool rest at an angle of 60 degrees relative to the working surface of the abrasive wheel (the end of the circle that faces you).

This helps to correctly orient the drill when sharpening. The angle shown in the figure is approximately 120 degrees in most cases. In general, the harder the metal for drilling, the larger this angle should be.

IMPORTANT! Do not use gloves while sharpening. Be sure to protect your eyes with glasses or a transparent shield. Be careful not to move your hand or forcefully touch the abrasive wheel.

Hands and fingers should not be strained.

5.3. Drill movement when sharpening

After installing the drill in its original position, slowly move it forward until it touches the circle. Immediately after touching, we move simultaneously in three directions: tip up, shank down, drill forward along the axis.

5.4

Repeat points 5.2 and 5.3 2 more times.

5.5

We rotate the drill around the longitudinal axis by 180 degrees and perform steps 5.2, 5.3, 5.4 for the second rear surface.

5.6. What should we get

Place the drill vertically, tip up. In this position, the entire back surface should be below the cutting edge. Moreover, the further from the cutting edge along the rear surface, the lower. In sharpening technologies this is called underestimation.

By grinding down the back surface, we lower it. As a result, only the cutting edges and the bridge touch the surface of the metal that the drill cuts. Lack of understatement is the most common mistake of novice sharpeners.

6. Technology for sharpening a metal drill using a grinder or hand drill

If you have figured out how to sharpen a drill on a sharpening machine, then it’s time to find out that this is done in a similar way on a grinder (grinder). As a tool, we simply use the edge of the protective shield of the abrasive disc. The rotation of the shield is adjustable.

Before sharpening, turn it so that it is comfortable to rest your finger under the drill being sharpened. Try to perform the same movements on the sharpening machine. The fact is that you can learn how to properly sharpen drills on a sharpening machine quite simply and quickly.

That is why it is recommended to fix the angle grinder - you will get a decent result faster.

It's more difficult with a hand drill. She has nothing to use as a tool. But you can use available items for this. Here you will need two stable, flat surfaces. A drill is fixed on one, the other is used as a tool. The surfaces are placed at the same level so that a disk mounted in a drill chuck can be placed vertically between them. For example, these could be tables, workbenches, drawers.

In any case, the quality of sharpening on a drill will be worse than on other tools considered.

7. Quality control of sharpening

During sharpening, you will have to constantly monitor the parameters of the drill elements. In most cases, this should be done after all back surfaces have been treated.

7.1. Visual inspection of the jumper

The jumper should be located in the center of the end of the drill tip. Besides. Its edge should pass between the deepest points of the chip evacuation grooves. In other words, it should be as short as possible.

7.2. Cutting edge length

This is the distance from the jumper to the edge of the drill along the cutting edge line. You can measure with a caliper or ruler. Obviously, all cutting edges must be the same. If this is not the case, then you should sharpen the back surface that is shorter.

7.3. Lowering control

We discussed what understatement is in paragraph 5.6. You can quickly check its presence by placing the drill vertically, tip down, resting the jumper on any flat surface. Look at the back surface from the side of the drill. If you do not visually see the understatement (the edge of the back surface, turned towards you, does not smoothly rise up), the surface will have to be re-sharpened.

8. Sharpening a step drill

If you have mastered sharpening a twist drill, then this will seem like a sandbox to you.
The photo in point 1 shows a step drill with a straight flute for removing chips. Lightly run the disc or grinding wheel along the cutting edges of the steps on the groove side. Be careful not to disturb the angle between the groove and the back surface of the step. Things are more complicated if the groove is spiral. Sharpening is also done, but more skill and accuracy will be required.

9. Sharpening the crown

Take a closer look at the tooth of the metal-cutting crown. You will easily find all the same cutting edges and back surfaces. There will be only a jumper and a groove for removing chips. Now you are competent enough to remove a minimum layer of metal from the back surface and get a sharp cutting edge. The crown may have a central twist drill. You already know how to sharpen it.

10.1. An attempt to fix not the tool, but the drill when sharpening with a drill or grinder

A heavy tool, with a rapidly rotating heavy rotor, will never become stable even in the hands of a strong man.

10.2. Excessive pressure when sharpening

It is better to repeat the cycle of operations 10 times with light pressure, checking the result after each cycle, than to turn a third of the drill into metal dust over the same 10 times.

Source: http://www.m-deer.ru/samodelkin/zatochka-sverla-po-metalu.html

Sharpening twist drills for metal

• 1 How to properly sharpen a metal drill with your own hands - detailed instructions
• 2 How to sharpen a metal drill using different tools
• 3 Do-it-yourself metal drill sharpening
• 4 Sharpening a drill for metal: parameters, tools for work, useful sharpening tips at home
• 5 How to sharpen a drill correctly
• 6 How to sharpen a drill for metal and what sharpening angles are there?
• 7 How to sharpen a metal drill with your own hands +
• 8 How to sharpen a metal drill yourself
• 9 Methods for sharpening twist drills
• 10 How to sharpen drills for metal
• 11 How to sharpen a drill for metal and concrete with your own hands
• 12 How to properly sharpen a drill for metal
• 13 Sharpening drills for metal: how to properly sharpen a drill with your own hands, video tips
• 14 How to sharpen a metal drill at home
  • 14.1 Drill wear
  • 14.2 Safety precautions

Drills come in different varieties, but in practice we often use those designed for working with metals. Despite the fact that such a tool is made from special grades of steel and is subjected to special hardening, it becomes dull over time.

A thrifty owner will never throw away even the cheapest twist drill, since its functionality is easy to restore on his own, especially since in a private house or garage such a person always has an “emery machine” (a simple sharpening machine).

How to sharpen a metal drill correctly will be discussed in this article. 

Sharpening varies, and this largely depends on both the diameter of the drill and the specifics of its application. For example, on the type of metal with which you are supposed to work (“hard” or “soft”).

What to pay attention to

• During operation, the edge is positioned strictly parallel to the working surface of the stone (the axis of the sharpener).
• The main thing is gradual sharpening. It is not advisable to “press” the drill too hard against the circle.
• The length of all edges must be the same.
• An indicator of the completion of the work is the absence of reflective glare on the surface being treated.

Recommended sharpening angles

You need to know that there is no universal meaning. For each type of material processed, its own sharpening angle is selected. Approximate values ​​are shown in the table.

Single-plane

Typically used for drills no larger than 3 mm. The disadvantage is that during the work, partial “chipping” of the edge may occur, so this technique requires special care. The point is that the tool is applied to the circle and moves parallel to its working surface.

Conical

Suitable for drills larger than 3mm. The tool is held with both hands, while sequential sharpening of the feathers is carried out (light pressure against the stone with a slight “swing”).

Finishing

It is advisable to do this after the drill has been sharpened. The task is to remove the smallest nicks and polish the cutting edges. For this, an appropriate stone (“soft”) is used.

Recommendations

For many people, self-sharpening a tool using electric sandpaper is associated with certain difficulties or becomes impossible. The reason is poor vision.

Judging by messages on various forums, neither good lighting nor glasses with large diopters help. Those for whom this is really a problem can be advised to purchase a special machine. For example, made in China. It is inexpensive - about 1,500 rubles.

And despite the fact that our attitude towards products from this country is, to put it mildly, “wary”, such products (for example, “Caliber-ezs 200s”) are spoken of very well by those who have already worked with them. The range of machines is quite large, so there is always a choice (Mikra-10 and a number of others).

To ensure greater sharpening accuracy and facilitate this process, a special device can be made. Its meaning is clear from the picture.

If you don’t have electric sandpaper at hand (and strict requirements for the angle), then you can use a grinder to sharpen the drill.

A video from respected master Viktor Leontiev clearly demonstrates the entire process, so if some of the nuances of sharpening remain unclear, it’s worth watching it:

Source: https://steelfactoryrus.com/zatochka-spiralnyh-sverl-po-metallu/

How to sharpen a metal drill correctly?

How to sharpen a drill for metal? This is a natural question after using it for a long time. Whatever material the drill is made of, it becomes dull over time, which makes the drilling process difficult. Sharpening can be done at home if you follow simple rules for sharpening drills.

Any drill needs to be sharpened from time to time.

Why sharpening is needed

The operating principle of any drill is based on cutting a thin layer of metal with sharp working edges as it rotates. As a result of constant contact with hard material, the cutting part of the drill gradually wears out, and this wear is uneven. The roundness of the tool is disrupted, and because of this, its runout occurs during drilling.

Flat drill sharpening.

Problems with a dull drill arise at the very beginning of work. Violation of the cutting cone angle creates difficulties when forming a starting cone on a metal part. The drill does not want to cut into the metal and slides along the surface. A characteristic indicator of drill wear and partial loss of its cutting ability is an extraneous sound, reminiscent of a squeak. It occurs already at the stage of drilling the part.

Significant dullness of the drill can be easily detected by touch by running your finger along the cutting edge, as well as visually by the appearance of a cone at its end. A worn-out tool significantly complicates the drilling process: the duration of the work increases significantly, drilling requires effort to insert the drill into the metal, and the quality of work noticeably deteriorates. To eliminate all undesirable phenomena, it is necessary to sharpen the drill for metal.

The most important parameters

In home workshops, twist drills of various diameters are used for metal processing. They are most often made of high-alloy steel, and the most durable are made of pobedit or using hardening solders.

All of them have the following main zones: working part, shank and neck. The shank is designed to secure the tool into the chuck of drilling equipment, for which there is a special foot.

The working part is made in the form of a spiral section, ending with a sharp tip - a cutting cone.

Elements of a twist drill.

The spiral-shaped work area includes two front (recessed) and rear surfaces. One of the boundaries between these surfaces is formed in the form of a ribbon with the formation of a cutting edge.

The lower end of the working area has a cone-shaped part, and at the top of the cone both surfaces converge, forming two toothed elements (feathers). On the side surface of the cone, a ribbon provides its cutting edge.

At the top of the cone, when two ribbons converge, a transverse edge and a bridge are formed, and the front surface forms a groove.

The functionality of the tool is ensured by the sharpening angles of its working elements. The main characteristic of a drill is the sharpening angle of the cone, which is defined as the angle between two strips at the conical tip. A decrease in the value of this angle leads to a lengthening of the conical cutting zone and a greater sharpening of the tool.

Given that different metals have different hardness, sharpening angles for drilling different materials vary. When machining almost all types of steel, a sharpening angle of 90 degrees is recommended. For drilling softer metals (copper, aluminum), its value can reach 100 degrees (as for wood).

When working with hard copper alloys (brass, bronze), an angle is selected within the range of 105-125 degrees.

Some rules for sharpening a drill

Sharpening a drill for metal is carried out to solve the following problems: maintaining the sharpness of the cutting edge, ensuring the required taper angle, and centering the tool.

This goal can be achieved by treating the working area with an abrasive element - an emery wheel, a grinder, etc. It is best to carry out the operation using special equipment, but sharpening can also be done manually, at home, or using tools.

The basic principle of the operation is fine processing of cutting areas while securely fixing the drill in the required position.

Twist drill and techniques for sharpening it.

Parameter control is carried out using a caliper and visually. It is recommended to use a template to estimate the cone angle. For drills with a diameter of up to 10 mm, the size of the jumper at the tip of the cone should not exceed 0.4 mm, and for diameters over 10 mm - 1.5 mm.

The degree and purity of processing depends on the grain size of the abrasive element. If the tool is significantly dulled, coarse sandpaper is used, followed by fine-tuning. If the nature of the defects is not very serious, then a fine-grained disc can be used. Minor wear is corrected with a velvet abrasive element (it is also used for finishing operations).

The degree of cylindricity of the drill (centering) is assessed by measuring the size of the ribbons from the conical tip to the beginning of the conical section. Their size must be absolutely the same. The cutting section itself should form a perfect cone.

Drill sharpening process

How to sharpen a metal drill correctly? Manual turning of a drill is carried out using a sharpening machine (emery) or a grinder when it is fixed in the form of a machine. The center of the tool is marked on the drill - a red mark in the conical tip. When sharpening, it moves horizontally relative to the surface of the workbench on which the grinding disc is mounted.

The surface of the area to be sanded should be parallel to the plane of the disc. In other words, when sharpening the conical part, the drill is brought to the circle at an angle, the value of which corresponds to half the sharpening angle of the cone.

Sharpening machine settings.

The cutting edge is sharpened by grinding the back surface. Both cone feathers must be processed absolutely identically. Sharpening the drill is carried out with two hands: the left hand ensures its fixation and movement, and the right hand ensures clockwise rotation.

Both hands should work synchronously, gradually moving the tool forward to sharpen the entire length. During the grinding process, it is recommended not to tear the part off the wheel. All movements should be smooth and calm. The progress of work is visually monitored by the red mark. After processing the first tooth, a similar procedure is carried out with the second feather.

The sharpening angle is checked with a template, and if the metal is not removed sufficiently, the operation is repeated.

If the tool is significantly worn, it may be necessary to sharpen the cutting edge of the cylindrical part. The processing of the ribbon on the back surface of this area is carried out at the end of the abrasive wheel. The drill itself moves towards the circle parallel to its surface.

Sharpening begins with installing a coarse-grained wheel on a machine or grinder. The next stage is processing on fine-grained discs. The operation is completed with finishing using a polishing wheel. In particular, a green silicon carbide wheel with a grain size of no more than 6 is recommended for the final stage.

When carrying out work, you should strictly monitor the heating of the metal, and for this, carry out regular water cooling.

Application of the device

When working with emery, the main problem is the correct direction of the drill and its reliable holding, taking into account the heating of the metal. To facilitate the process, tool holders are used. This kind of homemade system is common. The holder is made on the basis of a tripod with a plate attached to it.

The drill is secured to this plate using clamps. Its movement in the direction of the abrasive is carried out by an adjusting screw. The tripod stand is equipped with a scale with angle markings (usually the 4 most common options).

This design ensures reliable fixation of the tool in the plate clamps, and feed accuracy is ensured by the adjusting screw.

Necessary tool

Sharpening metal drills at home with your own hands will require the following tools:

• a sharpening machine or grinder with a set of discs of different grain sizes;
• sandpaper;
• vice;
• needle file;
• wrenches;
• file;
• pliers;
• template for cone angles;
• screwdriver;
• brush;
• calipers.

Any tool undergoes wear and tear during use, and drills are no exception. Their service life can be extended through timely sharpening.

Source: https://masterinstrumenta.ru/dreli/kak-zatochit-sverlo-po-metallu.html

How to sharpen a metal drill with your own hands - do it right

Not all people who are accustomed to working with their own hands know how to sharpen a drill for metal.

Processing materials, and especially metals, is always a complex process and includes many operations.

To carry out sharpening, you need a sharp, reliable device.

In addition, when buying a drill, it is important to understand that it will have to be sharpened quite often due to the frequency of use of the cutting part.

And if it becomes dull, then it becomes unsafe to work.

Frequently asked question: what to do with a wood drill? There is no need to worry here, because due to interaction with such a soft material, the tool can work without sharpening for more than one year.

But with metals the situation looks different - after a couple of months you can notice signs of loss of sharpness. How do you know when it's time to sharpen your tools?

The drill begins to hum or squeak when starting work. It generates heat and overheats.

Such a tool breaks down much faster, making metal processing impossible.

You can sharpen a drill using a machine or a special device.

If possible, it is better to trust such a process to professional equipment, but if you don’t have it at hand, you can really do everything yourself at home.

The most popular way is to make a machine with a sharpening stone at home, which is easy to use and does not require significant expenses.

The question of sharpening a drill for metal torments many people, because the center line of the cutting part can have a varied design: one cavity or two, and it can also be conical, cylindrical or helical.

Sharpening should be done correctly along the back edges. The angle at which the tool is fed into the machine plays a big role.

An incorrect angle can damage the drill beyond repair.

The cutting part itself consists of an edge - it must be the sharpest in order to cope with metals, as well as an auxiliary screw, a jumper, and the back and front surfaces.

Initial stage of work

First of all, let’s decide what you will need in the process of sharpening with your own hands.

When sharpening a drill for metal, and even with your own hands, you always have to look for an alternative to factory tools, because there are special sharpening machines in production.

At home, the minimum set for sharpening a metal drill will be more difficult to find. First you need to buy special grinding wheels.

Usually you need one circle, but with frequent use it will wear out quickly, so it is better to take several at once, for a reserve. The circle itself is installed on a rotating shaft with your own hands.

We also need a container and the coolant itself: here you can even choose water or engine oil.

While the drill is being sharpened, it will also heat up at the same time. If it is not cooled, then during operation it will fail faster due to the temperature difference.

It is equally important to maintain the angle; here eye control is unacceptable. It is because of this problem that people buy a special device so as not to constantly carry out tedious calculations.

It is necessary to know the angle of approach of the metal drill. The main angle is the rake angle, it can be defined in the main cutting plane as the angle between the front part and the base of the cutting part.

The rear angle has the same parameters, only on the rear plane. The angle at the top can be seen if you look at the metal drill from the side: it is located between the two edges.

It is believed that for the front angle you need to maintain a slope of 20 degrees, and for the rear - 10 degrees. The angle at the top is the same in all metal drills and has a value of 118 degrees.

Don't forget to take precautions when working with your own hands. Since we have to work with sharp parts, it is better to protect our hands with gloves. Be sure to wear glasses while sharpening.

In the process, small particles will fly off from the circle, which are also very overheated.

Watch the position of the tool, because if the feed angle is incorrect, it can be torn out of your hands.

Let's start the sharpening process

First, let's look at how to properly sharpen a drill yourself using sandpaper.

The main process falls on the back. We turn on the device with emery and, holding the metal drill tightly, bring it to the circle so that the cutting part is directed towards the sharpener.

We will get a parallel arrangement of the drill relative to the mechanism. Having sharpened the tool in this way, we get a high-quality drill for metals.

This simple sharpening is suitable for drills with a diameter of no more than 10 millimeters.

If it increases, then you can add the total sharpening time, pay more attention to the front side, and so on.

You can sharpen a drill in this way until the diameter exceeds 16 millimeters.

However, for devices with large diameters, or when working with dense metals, a machine may be needed.

This device allows you to make sharpening safer and correctly control the angle of inclination.

In addition, if you need to constantly be able to sharpen your tools, then your own machine will come in handy.

It is especially beneficial to install such a device at home if you need to sharpen carbide drills for metal.

There are certain requirements according to which sharpening should be carried out only on a machine:

• if we work with drills that are used to work in blind holes, with a reduction in the axial cutting force;
• working with universal tools that have great strength, which makes it possible to process durable metals;
• work with a point of smaller thickness if drilling to a significant depth is required.

The main task that the machine must perform is not just sharpening, but correctly orienting the drill along the metal relative to the circle. Therefore, its design has a base plate.

Both the machine itself and the engine, the shaft of which allows turning, are installed on it. There we also connect the rotary column on which the drill will be attached.

It rotates in a position convenient for us - another plus in the ability to position the tool.

Advantages of using the machine

Another feature that the machine provides is movement with the help of a motor.

Therefore, it is realistic to use any bearing assembly with a shaft as a column.

At the end of the shaft we will have a mount for the drill. It is best to use bolts for secure fixation.

After the tool is fixed, turn on the sharpener, and the column itself is brought to the circle so that the back of the metal drill is turned to sharpen.

This is convenient, because even before turning it on, we can set the correct angle to sharpen the drill.

There is also a machine that has a more compact design.

The main disadvantage of a conventional device is that you cannot take it outside the garage, and you need a lot of space inside the room.

Therefore, there is an option to use an attachment machine.

In such a device, on one side there is a connecting unit, thanks to which the attachment is installed on the drill spindle, and on the other, you can find a hole for drills for metals.

It’s easy to sharpen a tool in this way, even with your own hands - just insert it all the way and turn on the mechanism.

The riskiest option is sharpening with a grinder or other portable device with a moving wheel. What is the danger? It will be extremely difficult to secure the device.

And the slightest shifts during work can result in injuries. A grinder cannot achieve high quality; it is only suitable for metal drills with a small diameter.

And after the sharpening process, you cannot do fine-tuning.

Finishing is an important part of the process when it is necessary to sharpen a tool.

In factory conditions, it allows you to remove all irregularities at the end of the procedure and make the cutting part smooth.

If the drill is solid and uniform, it will last much longer and better.

If desired, finishing can be done at home. To do this, we simply change the circle to one made of silicon carbide.

What should those who have a pobedit drill bit with tips for the strongest metals do? Even it can be sharpened, despite the fact that such a device wears out much more slowly.

A diamond stone is used as a grinding wheel. With this process, an emery wheel simply will not give the desired results.

Before sharpening a tool, it is worth measuring the soldering, because if it is less than 10 millimeters, there is no point in sharpening. Only a complete replacement is needed.

Remember that the harder the tool material, the lower the wheel rotation speed should be.

And for a pobedit metal drill, the speed is generally at a minimum so as not to damage the cutting part.

Sharpening is carried out with short and smooth touches, excluding sudden movements.

If we are talking about soldering, then they are sharpened in the same way as ordinary drills - from the back side.

Source: https://www.stoydiz.ru/instrumenti-i-tehnika/kak-zatochit-sverlo-po-metallu.html

How to properly sharpen a drill at home

It is well known that during the working process any tools become dull and their cutting part becomes less sharp. Dull devices do not bother you until they are needed.

And when we start working with them, we understand that due to the unrestored geometry and size of the drilling device, it is absolutely impossible to make a hole.

Below we will take a closer look at how to sharpen drills correctly and learn the main differences in sharpening tools when working with wood, metal and concrete.

How to sharpen a twist drill

You can forget about sharpening twist drills for wood for a long time, since you can work with them for several months and years without sharpening. The same cannot be said about the tools that are used for metal. They must always be in a sharp, sharpened state. Otherwise, it will be almost impossible to drill through the metal.

The drill, losing its sharpness, emits a sharp, characteristic creaking sound. A dull edge overheats greatly and wears out faster than a sharp tool.

Sharpening of drilling tools is carried out on an appropriate machine using special devices or drill attachments for sharpening drills. Of course, if possible, it is better to do this using special equipment. But home workshops are not equipped with such machines; as a result, ordinary electric sharpening machines with a stone are used for sharpening.

Before sharpening a drill for metal, you need to decide on the type and shape of the sharpening. It can be single-plane, two-plane, conical, cylindrical and screw.

Sharpening is done along the back edge. The two cutting nibs need to be sharpened in the same way. This is quite difficult to do manually. In addition, it is difficult to maintain the required shapes on the rear edges and the desired rear angles.

1. The single-plane method is characterized by sharpening on the back surface of the pen using one plane. The value of the rear angle varies from 28-30°. To do this, the tools are placed parallel to the grinding wheel with the cutting part, after which they are sharpened without rotating or moving them. Such sharpening during drilling allows chipping of the cutting edge of the tool. Obviously, this is a significant drawback. This method is used for thin drills whose diameter does not exceed 3 mm.
2. For large devices, a conical sharpening is used. It is extremely difficult to produce it manually, but some craftsmen still practice it. It is necessary to take the tool in your left hand closer to the beginning of the cutting edge of the fence cone, and support the shank with your right hand. And begin to press the cone against the end side of the grinding stone with your left hand, and support the back part with your right, making slight rocking movements. During sharpening, the drill should not come off the sharpening tool; it must be carefully moved along the abrasive wheel.

When sharpening, you should try to exactly maintain the original shapes, as on the factory surfaces of the tool structure, in order not to violate the value of the back angles. If sharpened correctly, it will be absolutely sufficient for devices whose diameter does not exceed 12 mm. If the drills are larger in diameter, they can be modified by sharpening the front surface.

https://www.youtube.com/watch?v=wY2X2IkNmf8

By reducing the rake angles and increasing the angles of the cutting cone, wear resistance increases and chipping is minimized, which leads to an increase in tool life. Also, the width size at the transverse edges decreases. The transverse edges do not drill, but scrape the metal in the central parts of the holes.

On drills with a small back angle, additional pointing of the back surface is allowed. In this case, the cutting tools rub in the holes less strongly with their rear surfaces.

Production conditions after sharpening most often involve finishing, due to which the surfaces are smoothed and small nicks are eliminated. Tools that have been polished do not wear out as much as those that are simply sharpened without this procedure. If possible, it is better to try to do it.

For this, for example, a grinding round stone (green silicon carbide with bakelite bond) of grade 63C, grit size 5-6, hardness M3-SM1 or CBN LO wheels with bakelite and grit size 6-8 are used.

For a more complete introduction, there is an excellent selection of detailed video instructions, thanks to which you can learn how to properly sharpen a drilling tool.

How to sharpen tipped pobedit drills

Pobedite drilling tools can become dull, just like spiral ones. Dull drills overheat during the drilling process, barely drill and produce a strong squealing sound. Naturally, it is easier to replace the tool with a new one, but it is much more advisable to sharpen the existing one.

For this purpose, it is necessary to use a sharpening machine (electric sharpener), on which a diamond stone is installed and a coolant supply is provided. Ordinary emery stones are not suitable for sharpening Pobedit drills.

Before you start sharpening, you should find out whether it is possible to do it at all? To do this, you will need to measure the cutting part of the drill, namely its height. If it is more than 10 mm, then the sharpening process is acceptable.

Do not forget that the speed at which the tool must be sharpened depends on the hardness of the material. For high hardness, the speed should be low. The angular velocity indicators (rotation speed of the sharpener) when sharpening a drill from Pobedit should be reduced regardless of the tool used for sharpening.

Drills are sharpened by briefly touching the emery stone. Pobedite tools can be sharpened quickly; you just need to work on the areas where the edges have become wet. But this must be done extremely carefully so as not to remove the usable working part of the tool.

Experts recommend sharpening drilling tools with brazing in the same way as simple drills with a small diameter, making the sharpening on the rear surfaces flat. But you need to sharpen the back surfaces in such a way as to grind the drills down to the very tips, as can be seen in the photo.

It is also recommended to grind the front surfaces. If the soldering has previously been ground off almost completely, then sharpening is extremely necessary, since the soft metal elements extend to the cutting edges from the front surfaces. The front surface must be ground so that the thickness in the center of the solderings decreases.

When sharpening drills, try to maintain the same size of cutting sides. Failure to comply with these values ​​is fraught with the appearance of a displaced center of the axis, which will lead to unevenness of the holes being drilled and a shift in the center of gravity of the drill.

Regardless of the device where the sharpening process is carried out, it is important to maintain the ratio of the front and rear angles of the cutting edge, taking into account the rotating direction.

Also, another rule that must be followed is the correct sharpening of the drill for concrete: with greater hardness of the material, the sharpening angle should be large. For pobedit drills it is 170°.

When sharpening a drill, it is necessary to exclude the possibility of heating it. High temperatures can cause cracks to appear and peel off carbide inserts. To prevent the tool from overheating, use coolant. Even ordinary water can be suitable for this purpose.

“The process of sharpening a hammer drill” 

Below is a video selection that shows in detail the process of sharpening Pobedit drills.

Source: https://pro-instrymenti.ru/stroitelnye/kak-pravilno-tochit-sverla/

Sharpening a drill for metal: parameters, tools for work, useful sharpening tips at home

It is impossible to produce good processing of a metal alloy without the use of a device with certain geometric and mechanical characteristics. Therefore, the question of how to properly sharpen a drill for metal is of great concern to home craftsmen who work with these tools and materials.

Drills designed for processing metal alloys have to be sharpened much more often than products for wood.

When working with such a soft material as wood, the drills hardly become dull and can be used for a long time without losing their original properties. The situation is completely different with tools for making holes in metal parts.

The condition of this type of drill must be monitored regularly, and if wear occurs, appropriate measures must be taken promptly.

Some signs may indicate that a metal drill bit has become dull:

• hum and creaking noise produced by a worn-out instrument;
• excessive heating of the product during operation;
• low level of quality of the holes made.

A drill that is worn out is considered not only ineffective for use , but also dangerous. At any time, a tool whose working element is subjected to significant loads can break, and its parts, flying quickly in different directions, can easily cause severe injury to the master.

How to sharpen a drill correctly: sharpening parameters

In both domestic and industrial settings, drills for processing metal alloys can be sharpened using special machines that are equipped with a sharpening wheel (sharpener).

In these situations, it is recommended to use standard equipment. If you do not have access to it, then you can sharpen the part using a device made by yourself.

It is necessary to pay attention to the fact that the parameters of tools and equipment for sharpening tools also determine the result of the work.

The characteristics of self-sharpening drills include the following:

• the angle between the plane being processed and the back of the tool used;
• sharpening angle of the front plane of the cutting element;
• the length of the jumper located transversely on the cutting element;
• cutting tip angle;
• cutting edge length.

To make sharpening as high as possible, you need to place it in the processing area at the required angle. To cope with this, different accessories for sharpening machines are used.

It is also necessary to remember that if sharpening is done incorrectly , this can lead to poor quality results and tool malfunction.

Tools required for work

To sharpen drills yourself, you must first decide on the tasks that this procedure will solve. Under production conditions, special tools , which ensure the highest level of accuracy and efficiency. When working at home, you constantly have to select methods that would allow you to achieve the highest quality results.

So, the minimum set of sharpening tools should include:

• machine with emery;
• grinding wheels of varying degrees of hardness, which should be selected in accordance with the material of the rod;
• a vessel with a coolant liquid, which can be used as ordinary water;
• fasteners that allow you to hold the tool in the correct position when sharpening.

If you need to sharpen a tool at home or at work, then do not forget to follow safety requirements. As a rule, during work there are many sparks that can damage the performer's eyes. In addition, it is necessary to use protective gloves, since the work will involve the use of sharpened metal parts.

A machine with a grinding wheel is a universal equipment that allows you to perform sharpening very efficiently . When using it, work should start from the back of the drill. During processing, the part must be positioned strictly parallel to the grinding wheel. In addition, using a sharpening machine you can process tools with a diameter of no more than ten millimeters.

For elements with large diameters, it is recommended to use a special device that adjusts the sharpening angle. The main task of these additional devices is the correct placement of the cutting element of the drill relative to the surface of the sharpener.

It may seem that you can easily sharpen a tool using any equipment with a sharpening wheel. However, without the use of fixing devices it is impossible to achieve a high-quality result. In addition, using the wrong products can even be very dangerous.

Source: https://tokar.guru/instrumenty/sverla/zatochka-sverla-po-metallu-parametry-sredstva-dlya-raboty-sovety.html

How to sharpen a pobedit drill at home - Metals, equipment, instructions

Concrete drills are made of a hard special alloy. Drills most often have a soldered tip made of a very hard alloy based on titanium and tungsten. These drills can be used to drill stone, concrete, brick, ceramics, marble and some other similar materials.

Drills for concrete with a tip made of titanium and tungsten alloy, used for drilling stone, brick, marble, ceramics.

It is necessary to distinguish between drills and concrete drills.

They differ in the shape of the shank. The concrete drill is designed for an impact drill and has a standard shank shape, the same as an ordinary drill for metal or wood. The drill is intended for a hammer drill and has a shank for an SDS-design chuck. Today, there are 2 types of SDS shanks: some have a diameter of 10 mm, and others have a diameter of 18 mm.

To drill reinforcement, it is necessary to replace the drill with metal drills.

It should be borne in mind that the concrete device is designed to work with stone, concrete, ceramics and other similar materials. They should not drill into wood or metal. If, while drilling concrete, the drill comes up against steel reinforcement, you will need to replace it with metal drills, and then drill through the reinforcement. After this, you can continue drilling into concrete.

Today, there are methods that make it possible to sharpen such structures on concrete in such a way that they can also drill into metal. However, these methods are considered to be artisanal, and therefore, their use is not recommended.

Work process

When drilling (drilling) solid concrete, it is necessary to monitor overheating. Every 10-15 seconds you will need to let this drilling structure cool down. Under no circumstances should you cool it with water or any other liquids. High-quality modern drills can withstand fairly high heat (more than 1000 degrees).

It happens that a hard stone can get caught in concrete. If an impact drill is used, it may not drill through the stone.

In such a case, you can take a special chipper or some old similar drilling device for concrete and, using a heavy hammer or sledgehammer, you can try to manually crush such a stone. After this, you can continue with the drilling process.

The hard stone in concrete is crushed by hand using a heavy hammer or sledgehammer.

Drilling into stone and hard concrete is a somewhat labor-intensive process, especially if you plan to use an impact drill.

In some difficult cases, for example, when you need to make holes in ceilings or load-bearing walls, you should use a hammer drill in impact drill mode.

Especially when making a suspended ceiling and it is necessary to make holes to secure profiles in the concrete floor, you should not try to work with a drill. The apartment owner will only get tired and lose some time.

Sometimes concrete drills are sharpened using a grinder with a diamond blade. If the work is carried out using a hammer drill and there are high-quality drills, they will not require sharpening.

Do not use the impact drill mode when drilling ceramic tiles. Ceramics must be drilled using a concrete drill, but in the mode of an ordinary drill. Do not press too hard, otherwise the tile may crack.

Basic Rules

Dull concrete drill bits can be sharpened on a corundum grinding wheel.

Like any cutting tool, concrete drills will gradually become dull and lose their properties.

However, at home this happens somewhat slower, and therefore the cutting tool is most often not sharpened at all - the easiest way is to purchase a new one.

However, if there is such a need, carbide tips of drills can be sharpened on a corundum grinding wheel in the same way as ordinary devices.

It is imperative to take into account the fact that concrete drills are afraid of heating when sharpening - in this case, the carbide plates fall off and crack. Therefore, the tip will need to be cooled with water from time to time, and then ensure that the drill does not get too hot on the sharpening stone.

If the tip does get hot, it is strictly forbidden to immerse it in water - the plate will immediately burst. This drilling device must be allowed to cool slowly and gradually in the air.

To protect the drill bits from heating up when sharpening, the tip must be cooled with water.

In case of correct sharpening, the cutting edges must be straight, and their intersection must exactly coincide with the axis of rotation of the drill. If the length of the cutting edges is not the same, the short one will be less loaded during operation than the longer one. Consequently, the long one will become dull much faster.

In addition, under the influence of increased loads from the longer edge, the drill may begin to be pushed away from the axis of rotation. As a result, the drill may break.

If the sharpening angles of the cutting edges turn out to be different, only the edge that has a larger sharpening angle will work.

This can also lead to the risk of breaking the drill during operation and to a one-sided load.

Several ways

A drill, penetrating into the material being processed, must come into contact with the workpiece exclusively with its cutting edges. All other points on the flank surface must have clearance with the bottom of the hole (cutting surface). For clearance to exist, the shape of the back surface must be different from the shape of the bottom of the hole.

There are a fairly large number of possible sharpening methods that make it possible to create the desired clearance angles, the gap between the back surface of the drill and the cutting surfaces. Depending on the shape that the back surface will receive, they can be divided into helical, conical and flat sharpening methods.

Using a conical sharpener

When conical sharpening a drill, it is necessary to correctly set the geometric parameters.

Conical sharpening is the most common method. The drill is installed in a prism, which has the ability to swing around an axis that is inclined to the working surface of the grinding wheel. The swing axis and the drill axis are crossed. This means that they will lie in two parallel planes.

The drill, which is fixed in the prism, is brought to the grinding wheel. The rear surface will take the shape of a section of a conical surface. The vertex of the cone will lie at the intersection of the generatrix of the working surface of the circle with the swing axis.

1. The distance between the crossing axis of swing, which is the axis of the sharpening cone, and the axes of the drill (h).
2. Distance from the drill axis to the tip of the sharpening cone (H).
3. The angle of intersection between the axis of the sharpening cone and the axis of the drill (o).
4. Half the sharpening cone angle (b).

Two types of conical sharpening are used:

To obtain other values ​​for the inclination of the transverse edge, change the parameters and settings.

1.  The tip of the sharpening cone is located higher than the tip of the drill. In this case, the settings will be as follows: a = 45 degrees, b = 13-15 degrees, H = 1.9D, h = (0.05-0.08)D. The angle of intersection of the axis of the drill and the cone in this case is less than the angle φ0 between the axis of the generatrix of the grinding wheel and the drill.
2.  The tip of the sharpening cone is lower than the tip of the drill. The distance of the tip from the drill is H = 1.16D, half the sharpening cone angle b = 30-35 degrees, the intersection angle of the drill axis and the cone axis is o = 90 degrees, offset h = (0.05-0.08)D. For this type of sharpening 0 > f0.

The specified installation parameters are capable of providing clearance angles for the peripheral point a = 5-7 degrees, a leading angle 2f = 116-118 degrees, and an inclination angle of the cutting transverse edge Ф = 55 degrees.

If there is a need to obtain other values ​​of the rear angles a and f (inclination of the transverse edge), the setting parameters should be measured.

The clearance angle is adjusted by changing the distance h between the crossing axes of the drill and the sharpening cone. The inclination angle of the cutting transverse edge (φ) is by rotating around an axis, the plan angle is a change in the angle o and b. With increasing distance between the axis of the drill and the axis of the sharpening cone (h), a will increase, and angles φ and 2φ will decrease. An increase in o, b and H, on the contrary, reduces 2f, f and a.

The clearance angle, which is measured in cylindrical sections, increases as it approaches the drill axis during conical sharpening.

Cylindrical section of the drill.

The first type of sharpening is capable of creating a sharper increase in the rear angles. Such a change in the rear angles is favorable. This is explained by the work of the drill. In addition to the rotational movement during operation, the drill will move along the axis.

Consequently, the trajectory of each of the points is a helix. This line is inclined to the cutting plane, which is determined without taking into account the axial movement of the drills at an angle m.

Its value is determined by the formula tg m = So / pD, where So = feed, mm/rev.

The actual clearance angle will decrease by a value of m. The closer the point in question lies to the drill axis, the more the clearance angle, which is measured during operation, will decrease. Consequently, an increase in clearance angles closer to the axis, which can be obtained with conical sharpening, will help increase durability.

Use of screw

When using the screw method, automation of the sharpening process is possible.

Screw sharpening is the easiest method to automate sharpening. The drill will be given rotation and two translational movements, which are coordinated with it, in relation to the grinding wheel.

One of the movements is directed along the generatrix of the circle, the other along the axis of the drills. Oscillating is the movement along the generatrix of the circle parallel to the cutting edge, because it will not create back angles.

The backing movement is along the axis of the drill. During the screw sharpening process, there are 2 sections on the cutting edge: section 0-1, which is located on the diameter of the core. Sanded with a wheel edge. Section 1-2 of the circle's generatrix.

In section 0-1, a sharpening of the jumper can be observed. In this section, the plan angle will decrease by the value of the angle v, which is formed by the vector vc.

It is equal to the sum of the oscillation vectors v0 and the backing vectors v3 with the direction of the oscillation vector.

In a cylindrical section, the back angle in section 1-2 will be determined by the value of the backing vector: tg a = 2 | v3 | / (wD) or tg a = 2H3 / (nD), where H3 is the backing stroke, w is the angular speed of rotation of the drills.

The oscillation stroke is assumed to be approximately equal to or slightly greater than the core diameter. Relief angles will increase with increasing backing stroke. The clearance angles will not change as the oscillation stroke increases.

  How to cut plexiglass at home

Diagram of screw drill angles.

Just as with conical sharpening, with helical sharpening the clearance angles, which are measured in a cylindrical section, increase as they approach the axis of the drill.

In this case, the increase in the rear angles occurs to the same extent as their decrease as a result of the peculiarities of the drilling kinematics.

Consequently, when setting even small clearance angles on the periphery, it will be possible to obtain clearance angles of the required size close to the drill axis.

When sharpened with a screw, the transverse cutting edge will become less durable as a result of sharpening. This will worsen the operating conditions of drills during drilling of strong and hard materials and cause increased wear of the transverse edge due to increased specific loads.

In the process of drilling materials of relatively low strength (aluminum alloys, cast iron and others), the strength of the tips will be quite sufficient. The drill can easily penetrate the material being processed. This can significantly improve drilling productivity and accuracy.

When working with solid carbide drills, two-plane sharpening can provide high durability when drilling material of relatively low strength and hardness - aluminum alloys, cast iron, non-metallic materials. When drilling hardened and difficult-to-cut steels with two-plane sharpening, increased wear of the cutting transverse edge near the centering point at the tip will be observed.

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Source: https://spb-metalloobrabotka.com/kak-zatochit-pobeditovoe-sverlo-v-domashnih-usloviyah/