Sharpening a drill for metal: how to properly sharpen a drill at home
It is impossible to perform high-quality metal processing (including drilling a hole in a metal part) without using a tool whose mechanical characteristics and geometric parameters correspond to the required values. That is why the question of how to sharpen a metal drill correctly is relevant for home craftsmen who often work with such a tool, which wears out (naturally) during use.
Sharpening a drill for metal using a special device greatly simplifies the task
Drills intended for metal work have to be sharpened much more often than those used for wood processing.
When processing such a soft material as wood, drills practically do not become dull and can be successfully used for a very long time, completely retaining their original characteristics.
The situation is completely different with drills, which are used to make holes in metal parts. It is necessary to constantly monitor the condition of such drills and take immediate action if their working part is worn out.
A number of signs indicate that a metal drill needs to be sharpened:
- creaking and humming noise produced by a worn-out instrument;
- intense heating of the drill during its use;
- low quality of created holes.
For a drill with different lengths of cutting edges, only one side works and the chips exit along one spiral flute
Working with a worn drill is not only ineffective, but also unsafe. At any moment, such a drill, the working part of which bears significant loads, can break, and its individual fragments, flying in different directions at high speed, can cause serious injury.
Drill sharpening parameters
Both in industrial and at home conditions, metal drills can be sharpened on emery machines equipped with a sharpening wheel of appropriate hardness. It is best to use commercial equipment in such cases.
If it is not available, then you can sharpen drills on devices made by yourself.
It should be borne in mind that the characteristics of this equipment, as well as the devices for sharpening drills used in conjunction with it, largely determine the quality of such a procedure.
Basic forms of sharpening twist drills
The most important parameters that should be taken into account in order to properly sharpen a metal drill with your own hands are:
- the angle at which the back of the tool is positioned to the drilling plane;
- sharpening angle of the front surface of the cutting part;
- length of the transverse bridge on the cutting part;
- cutting tool tip angle;
- length of cutting edges.
Basic drill sharpening parameters
In order for the drill to be sharpened with high quality, it is necessary to ensure that it is fed into the processing area at the required angle. To solve this problem, various devices are used that are equipped with sharpening machines.
It should be kept in mind: if sharpening a drill for metal is done incorrectly, this can lead not only to a poor-quality result, but also to breakage of the tool.
Influence of point angle on proper chip formation
What is needed for the procedure
To sharpen a metal drill yourself, you must first determine what tasks it will be used to solve. In production conditions, for sharpening drills, special devices are usually used to ensure maximum accuracy and productivity of such a process. When sharpening drills at home, you always have to look for ways to make the result of this process high-quality.
The minimum set for sharpening metal drills should include:
- emery machine;
- grinding wheels of varying hardness, selected depending on the material of the drill that needs to be sharpened;
- a container for coolant and the liquid itself, which can be ordinary water (or engine oil);
- devices that allow you to maintain the correct sharpening angles.
The drill stand is installed next to the abrasive disc and allows you to sharpen the cutting edge at a precise angle
When sharpening drills with your own hands, you need to pay attention to the following parameters:
- the angle between the plane of the front part of the drill and the base of its cutting edge (this angle, measured in the main cutting plane, is called the front);
- rear angle, which is measured in the same way as the front angle, but along the rear plane of the drill;
- tool tip angle measured between two cutting edges.
To sharpen drills for metal, according to all the rules, you must adhere to the following values of the above parameters:
- front angle of the cutting part – 20°;
- back angle – 10°;
- apex angle – 118°.
Table 1. Drill point angles depending on the material being processed
Table 2. Back and front angles of the drill
If you need to sharpen a metal drill in production or at home, you must strictly follow safety precautions. This process is accompanied by the formation of a large number of sparks, from the effects of which it is necessary to protect the organs of vision. In addition, since this procedure is performed with sharply sharpened metal instruments, it should be carried out using gloves to protect your hands.
Practical recommendations
An emery machine equipped with a sharpening wheel is a universal device that allows you to sharpen a drill for metal with high quality even at home. Using such a device, the technological operation should begin with processing the back surface of the tool.
The drill to be sharpened is held in relation to the grinding wheel so that its cutting part is parallel to the surface of the wheel. Sharpening performed using this method is optimal for metal drills whose diameter does not exceed 10 mm.
To efficiently sharpen drills with a diameter greater than 16 mm (including those equipped with carbide plates), it is best to use an emery machine with a special device. The use of the latter allows not only to control the sharpening angle of drills of significant diameter, but also to carry out this process with maximum safety.
Accuracy of sharpening in a special device is achieved by precise fitting and reliable fixation of the drill in the mandrel
Sharpening machines equipped with additional accessories are recommended for use in cases where it is necessary to sharpen drills of the following categories:
- used for drilling blind holes, which is characterized by a decrease in axial cutting force;
- universal, characterized by increased strength;
- used for drilling deep holes and characterized by a small point size.
The main task that devices that allow high-quality sharpening of a metal drill on a sharpening machine solve is the correct orientation of the cutting part of the tool in relation to the surface of the abrasive wheel. That is why the design of such a device has a special base plate.
The machine itself, the motor that rotates the grinding wheel, and the rotary column on which the tool being processed is fixed are installed on it.
The use of such a column allows you to sharpen drills in almost any spatial position, positioning their cutting part in relation to the surface of the grinding wheel at the required angles.
Benefits of using special devices
The big advantage of using sharpening machines equipped with special devices is that the movement of the tool being processed is ensured by a drive connected to an electric motor. The design of such a drive includes a bearing assembly and a shaft. At the end of the latter there is a drill that needs to be sharpened.
Before starting the procedure, the tool is fixed on the device at the required sharpening angles. After the metal drill is fixed on the movable column of the device, it itself is brought to the rotating grinding wheel. Thus, all the angles that need to be formed on the back surface of the cutting part are maintained automatically during the sharpening process. Among the main disadvantages of such a machine for sharpening drills, its large size is usually noted.
If you are looking for an answer to the question of how to properly sharpen a drill for metal without performing complex manipulations with the tool being processed, we can recommend more compact devices. One such device is a nozzle machine.
It is installed on the spindle of a conventional electric drill, from which its main working element, the grinding wheel, is rotated.
One end of such a device is equipped with a special coupling that connects the device to the rotating spindle of an electric drill, and the other is equipped with a cover with holes of different diameters into which the working parts of metal drills to be sharpened are inserted.
Drill attachment for sharpening Sparta drills
It is very easy to teach someone how to use this device, which allows you to quickly sharpen a drill at home. In this case, you don’t even have to show such a process on video or live, everything is clear without demonstration.
To sharpen a drill for metal using such a device, it is enough to insert the tool into a hole of the appropriate diameter until it stops and turn on the electric drill, which will rotate the sharpening wheel.
A tool sharpened using such a simple device has all the required geometric parameters.
It would seem that you can sharpen a drill using any device that can rotate a sharpening wheel. Meanwhile, without the use of devices for fixing the tool during the sharpening process, it is impossible to perform such a procedure efficiently. In addition, serious injuries may occur. You can use this simplest sharpening method only if you need to sharpen small-diameter drills that are easy to hold in your hands during processing.
When sharpening manually, a corner attached to a support will help you maintain the required parameters.
After you have sharpened a metal drill, you need to perform a technological operation such as finishing. It is needed in order to bring the quality of the cutting part of the restored tool to the required values. Finishing is carried out using sharpening wheels with a small grain size.
At the same time, all irregularities are eliminated from the cutting part of the drill and it is given smoothness. Drills with no roughness on the working part create less friction during the drilling process, heat up less, and therefore can last longer.
To perform finishing operations both in production and at home, grinding wheels made of silicon carbide are used.
An important condition for high-quality sharpening is the absence of vibration of the abrasive stone
Drills, the working part of which is equipped with hard alloy tips, can also be sharpened, but a number of nuances should be taken into account.
Carbide inserts are very critical to overheating, so such drills for metal can be sharpened efficiently only at low rotation speeds of the grinding wheel.
In addition, when sharpening, you must ensure that the tool does not overheat. Otherwise, the carbide plates will crack or even break off at the soldering point.
To sharpen carbide inserts, you can follow the processing technology of conventional cutting tools. It should also be borne in mind that for sharpening drills with carbide plates, diamond-coated grinding wheels are used, since only they can effectively handle the processing of such hard material.
In order to become more familiar with the rules and methods of sharpening metal drills, it is better not to limit yourself only to theoretical material, but to study the relevant videos. The technological process shown in all details will allow you to sharpen your tool efficiently and quickly.
Source: http://met-all.org/oborudovanie/prochee/kak-zatochit-sverlo-po-metallu-svoimi-rukami-video.html
How to properly sharpen a drill at home
Sharpening a drill at home is not difficult if you know how. The difficulty in this matter is maintaining the correct angles. After all, at home, as a rule, there are no special mandrels and conductors. There is only a sharpening machine. At least, we will proceed from such conditions.
Equipment requirements
The only equipment we have is an electric sharpening machine. But just because it exists does not mean that you can sharpen drills on it. It is necessary that the sharpening disk has the correct shape - that is, the shape of a cylinder with a smooth, not rounded edge. A convex edge with ground edges may result in incorrect sharpening.
If the disk is very worn out, it is better to replace it with a new one or correct it with a special CBN “pencil”, if you have one on the farm. It is very good if the disk is balanced and does not produce beats or vibrations (in fact, this is a mandatory norm). Only the peripheral surface of the disk is involved in the work, not its ends.
There is a temptation to use the flat side surface of the disk. But after several sharpenings it will lose its shape and fixing the stone after that will be much more difficult.
Sharpening auger for concrete
The hammer drill has a carbide plate as the cutting part, inserted into a slot at the working end and secured with solder. A normally sharpened drill has clear cutting edges with a sharpening angle of about 900 and an angle between the edges at the apex of 130–1400.
During standard sharpening, the front edge of the cutting edge (directed in the direction of rotation) is inclined to the drill axis at an angle of 300, and the rear - at an angle of 600. When manually sharpening, without special tools, you can focus on the whole, unworn part of the edges and reproduce their angles of inclination .
Sharpening process
We start sharpening from the front edges. We position the drill near the peripheral surface of the stone so that the cutting edge is parallel to the axis of the sharpener and directed upward, and the edge is parallel to the surface, and lightly press the drill against the sharpener for a short time.
A clearly visible mark remains on the metal, which shows whether its position was chosen correctly. The plane of the test section should coincide with the plane of the edge, and the spot of the section should be located in the center of its unworn part, without significant displacement.
Having found the correct position experimentally, remember it and begin sharpening.
Parallelism is not difficult to achieve if you bring the cutting edge to the surface of the stone and navigate along the gap left before contact.
You should not immediately achieve a sharp edge. Remember that you still have to grind down the back edge, and then the edge will “fall into place.”
First, the front edges are sharpened one after another. Then you need to check their symmetry. This is done visually, in the light, by placing the drill head near the edge of an object. The edge should be smooth or concave, but symmetrical. You can make a special template for testing. If there is asymmetry, a shorter edge is additionally ground down.
After this, the back edges of the edges are also ground down one by one, followed by checking for symmetry. The symmetry of the arrangement of the edges is also checked when viewed from the end, along the axis of the drill. When sharpened correctly, they are parallel, and between them there remains a bridge about 0.2–3 mm long, depending on the diameter.
If, as a result of processing, the cutting edges do not become sharp, there are visible roundings or cavities on them, the entire sharpening cycle must be repeated.
Add-ons
When sharpening, it is important not to overheat the tool. To cool, it is periodically dipped in water. A container of water should be kept near the machine. Do not press the drill against the sharpener for a long time. It is better to work with short touches, about 2–4 s, with breaks for the same amount of time. In this case, excess heat has time to be removed by the body of the drill and the risk of overheating the edge is reduced.
To work on soft materials without impact, for example on brick or tile, the cutting edges are brought “to zero”, without a jumper, and their sharpening angle is reduced to 30–350.
How to hold the drill while processing
Since, according to the conditions of the task, we do not have devices for precise positioning of drills, all hope is in our own hands. There are several simple techniques to achieve a “steady hand.”
It is best if, when sharpening a drill, you can rest it on a tool rest - a special “table” fixed in front of the sharpener. If you cannot achieve the desired position with direct support on the tool rest, you can hold the workpiece in your hands, but be sure to lean on it:
- fingers on the rest;
- with your wrist or hand on a workbench, on your knee, on any stable and conveniently located object;
- elbow or forearm on a workbench or knee.
As a last resort, you can simply press your elbows to your sides, forming a triangle with your arms and torso. But in any case, you need to find a way to hold the tool as tightly as possible with minimal effort.
When fixing the drill during operation, you should remember its position not only visually, but also by the sensations in your hands. Muscular, kinesthetic memory may be more accurate than visual control.
To maintain sharpening symmetry, it is useful to move to the second edge by turning the drill around the longitudinal axis, without changing the position of the hands and body. If you don't need a cooling break.
Sharpening a drill for metal
When sharpening drills for metal, only the back surfaces of the cutting edges are ground down. These surfaces have a rounded shape (flat if the drill diameter is less than 3 mm) with a decrease relative to the edge of about 100. The cutting edges converge to the top of the drill at an angle of 116 - 1200 (sharpening angle). For brass, copper, soft bronze, this angle is increased to 125–1300, for aluminum - up to 1400.
Sharpening
When sharpening, the drill is held with both hands. One near the sharpener, the other by the shank. The fingers of the hand closest to the sharpener (leading) rest on the rest. If it is not there, you need to find any support, as described above.
The drill is positioned at an angle to the working surface of the whetstone: 600 horizontally (half the angle at the apex) and about 100 vertically. The sharpened cutting edge is directed upward and located horizontally, parallel to the axis of the stone.
The position can be selected when the machine is turned off, according to the shape of the gaps between the edge and the sharpener when viewed from above, and between the sharpener and the back surface when viewed from the side.
To more accurately set the sharpening angle, you can draw a clearly visible line on the tool rest at the desired angle.
When sharpening, the drill is pressed against the sharpener by the cutting edge, and then, without changing the pressure and horizontal angle, it is tilted with the shank down until the back surface is completely processed. In this case, the position of the leading hand does not change. After 1 – 3 such passes, the drill is rotated around the longitudinal axis by 1800, and the operation is repeated for the second edge. The tool is rotated only with your fingers, without changing the position of your hands.
After sharpening, you need to check the symmetry of the edges - the equality of their lengths and angles of inclination to the axis of the drill. If one of the edges is shorter, it needs to be sharpened again. The equality of the angles is checked visually - against the light or using a simple template; the length of the edges can be measured with a caliper.
Additional processing
When sharpened correctly, the cutting edges do not meet at the top; a short bridge remains between them. To reduce resistance to entry into the material, the bridge is ground off with the angle of a sharpening stone or a diamond file.
Grinding is carried out on both sides, symmetrically, at an acute angle to the drill axis, and the edge of the resulting groove is located at an angle of 300 to the cutting edge.
The purpose of this operation is to shorten the jumper, but not to grind it off completely! Without it, the drill will not be centered upon entry.
The lintel is stitched using drills with a diameter of more than 3 mm. But in practice, for simple work without high loads, the jumper, as a rule, is not ground down even with a diameter of 10 mm or more.
Checking the sharpness
After sharpening, you need to check the tool in operation and, if necessary, correct it. There are several signs that indicate sharpening errors.
- Poor alignment at the entrance; during operation, beating is noticeable - asymmetrical sharpening of edges or bridges.
- When working, you can hear the squealing of metal, the drill gets very hot, the chips look like small grains - a large angle of sharpening the edge, insufficient lowering of the back surface (blunt edges).
- Increased rotational force, chips quickly form on the cutting edges - the sharpening angle of the edges is too small (excessively sharp edges).
Signs of proper sharpening:
- clear centering at entry, stable operation, no beats;
- entry into the material is easy, chips come out in the form of identical “spirals” from both grooves;
- The heating of the drill is low.
Wood drill sharpening
There are several types of drills for drilling wood and wood-based materials. Here we will consider the most universal and common - spiral.
Features of drilling wood
A twist drill for wood differs little in design from its counterpart for metal. Even the cutting part may be the same. But wood has a fibrous structure. When drilling it, the cutters in different directions interact with the material differently. The consequence of this may be scuffing and chipping on the surface of the workpiece. To avoid this and get a neat, even hole, use a special sharpening of the drill, with a center and trimmers.
The first to come into contact with the material is the centerpiece - a narrow spike located along the axis of the drill. As it goes deeper, it centers the tool and keeps it from moving laterally. Then the scorers come into play - the side incisors protruding above the cutting edges. They cut wood fibers along the contour of the hole and prevent the spread of flakes beyond its boundaries. The contoured, virtually isolated material is extracted by the main blades.
Geometry of the working part
The angles of inclination of the center faces to the drill axis are 100, the inclination of the inner edges of the scorers is 300, the outer edges of the scorers coincide with the side surface of the drill. The angle of depression of the rear surface of the cutting edges is 250. The height of the center and scoring tools above the cutting edges depends on the diameter of the drill, but the scoring tools are always lower.
For example, a drill with a diameter of 10 mm should have a center height of 3.5–4.5 mm, and scorers should be 1 mm high. The width of the base of the center is about 1.5 mm. For recommended parameters for different diameters, see Tables 1 and 2 of Appendix 1 to GOST 22053-76.
What to sharpen
To perform such a complex sharpening you need a specially shaped stone. If you have a “pencil” for straightening abrasive discs, you can give a standard sharpening disc a trapezoidal profile (grind one edge to a cone) and use this stone for sharpening only wood drills.
You can also use a grinder disc by installing it on a sharpening machine. For different mounting diameters, an adapter can be ordered. Another option is to use a grinder. But it must be securely fastened.
Sharpening is a familiar job
The process of sharpening a wood drill is, in principle, no different from sharpening other drills. The same techniques are used for selecting the desired angles, fixing the tool and controlling symmetry. If you just need to sharpen a dull drill, then with good equipment there should not be any big difficulties. If you need to make a wood drill from a standard one, then you should first practice on old drills, which you don’t mind using lime for training.
Source: https://instrumentiks.ru/sovety/kak-zatochit-sverlo
How to sharpen a metal drill with your own hands from theory to practice
Over time, even the best-quality drill becomes dull, penetrates the metal less and less well, and does not allow making an even hole of the required accuracy. In most cases, there is nothing left to do but sharpen a metal drill without leaving your workplace.
Sharpening drills allows you to fully restore their characteristics and performance. Of course, purchasing a new product is much easier than fixing the problem yourself.
To sharpen it correctly, it is not at all necessary to have special equipment: you can restore the drill using a simple tool.
How does the sharpening angle of a metal drill affect drilling efficiency?
At home, work is often done to make holes of the required size in metal. When drilling, it is not always possible to quickly replace a worn-out tool with a new one of the required size. Home craftsmen try to select the required diameter, but if the sharpening angles of the drills are not maintained, then it is problematic to quickly and efficiently complete the task.
The discrepancy between the sharpness of the cutting edge and geometric parameters can be determined by a number of signs:
- increased noise level emitted by an unsharpened shank;
- intensive increase in the temperature of the workpiece during machining;
- sudden heating of the working part and the body fixed in the cartridge;
- unsatisfactory quality of formed holes;
- an increase in the axial force applied to the electric drill;
- the quality of the chips, which crumble and do not have a spiral shape.
Drills intended for metal work have to be sharpened much more often than those used for wood processing.
In addition, the load on the electric motor increases significantly when trying to apply a force in the axial direction sufficient to immerse the cutting edge into the metal. The dullness of the chamfer is a source of additional resistance between the cutting part and the processing surface. Knowing how to properly sharpen a drill for metal, if any of these signs are detected, you must immediately stop drilling and begin restoration.
A worn working part not only reduces machining efficiency, but also affects safety. At high temperatures and elevated temperatures, performing machining at significant speeds, breakdown is possible. Metal fragments can fly in all directions and cause serious injury.
Working part
The working part is formed by 2 cutting edges, which are obtained as a result of the intersection of the helical surfaces of the grooves intended for chip removal, as well as a transverse cutting edge, resulting from the intersection of the rear surfaces.
Preparing drills for drilling in metals at home using a sharpening disc can only be done for drills whose diameter does not exceed sixteen millimeters. It is best to do precise sharpening using different devices or on a specialized machine.
The guide part consists of two auxiliary cutting edges, which are obtained as a result of the intersection of the front surfaces with the surface of the strip.
Elements of a twist drill, as well as the geometry of its angles.
The names of the elements are shown in the figure.
- with single sharpening
- with double sharpening
- D – outer diameter of the drill.
Almost the decisive influence on the quality of the resulting holes is exerted by the angle, denoted on the diagrams and drawings of drills by the Greek letter ϕ (2ϕ) or the apex angle. If it is made too small, then the lower edge of the chip will be inhibited by the wall of the hole. Difficulties in the process of removing chips will lead to overheating of the drill metal and, as a result, to rapid wear.
It is also important to maintain the exact values of this angle when sharpening because when it increases, there is a proportional increase in the load on the cutting edges, which means that the resistance of the metal being processed to penetration of the drill into the part during feeding increases. If the tip angle is less than optimal, then the force required to ensure rotation of the drill at the optimal speed increases, chip formation deteriorates, and friction increases.
As a rule, the 2ϕ angle for universal drills, which are made from high-speed, or chromium, or carbon steel, should be 116˚-118˚. It is changed during sharpening depending on the metal in which the hole needs to be drilled:
- hard bronze, cast iron, steel - 116˚-118˚;
- soft bronze, brass - 120˚-130˚;
- red copper - 125˚;
- magnesium alloys - 90˚;
- silumin, electron - 90˚-100˚;
- aluminum - 140˚;
- ebonite, marble, fragile materials - 140˚;
- various plastics - from 90˚ to 100˚;
- wood - 140˚.
Professionals advise buying several drills with the same diameter. Then you will be able to work without interruptions for sharpening, and do it when the entire set becomes dull.
Sharpening drills - preparatory activities
Home craftsmen are often upset by the impossibility of further implementation of plans due to the fact that the drill has become dull. How to sharpen it yourself? Indeed, in the conditions of manufacturing enterprises, special equipment is used to solve such a problem.
It allows for increased accuracy, securely fixes the cutting shank and restores the condition of the cutting edge in a limited time. When thinking about how to sharpen a metal drill at home, check what household power tools are available.
The following equipment will be suitable:
- Sander;
- grinder;
- electric drill.
You should carefully consider what you will need to complete the work and what you will need to add to the power tool.
Sharpening a drill for metal using a special device greatly simplifies the task
Source: https://instanko.ru/osnastka/kak-zatochit-sverlo.html
How to properly sharpen a drill for metal: methods and videos
Tools become unusable over time: they become dull, break and crack. Not all consequences of use can be eliminated, which is why you have to purchase new devices, but some can still be restored and given a second life. This is especially true for drills, which during use can not only break, but also become dull.
- Types of drills for metal
- How to sharpen a product at home
- Methods for sharpening drills for metal
- Finishing after sharpening the drill
- Recommendations for sharpening metal drills
Types of drills for metal
Today it is possible to make a hole in non-ferrous metals, steel, cast iron without the use of special equipment. For such purposes, you only need a high-quality drill and good drill bits.
This type of product comes in different shapes. For example, a cutting tool in the form of a spiral , which is formed by several longitudinal grooves that remove chips. Such a device is usually called a spiral device.
A metal drill can also be of this type:
The latter type has a conical shape . Using this product, holes of various diameters are drilled depending on the final and initial circumference of the cone. It is easier to work with the former, because each step in them means a certain diameter, and when using the latter, you will have to constantly monitor the process.
Core drills are best used for drilling large diameter holes. They are also effective for multi-layer drilling of several sheets of metal at once. Due to the design of these products, there is no need to use more powerful tools, since the cutting forces are kept low.
In order for the core drill to last as long as possible, it is necessary to ensure that there is no vibration and the metal is cooled. When purchasing them, you need to pay attention to tools with reinforced shanks that do not slip in the chuck.
Shanks are mainly produced in conical and cylindrical shapes. Hexagons are very rare. Tools with a cylindrical shank are fixed in a three-jaw chuck, so their diameter does not exceed 12 mm.
Of course, industrial products with a tapered shank are designed for drilling machines. Their maximum size can reach 60 mm. If the cone of the tool and the spindle do not match, then use an adapter sleeve .
Drill markings
Drills are marked with special symbols. They most often indicate the steel grade and diameter. True, on too small instruments up to 2 mm nothing is noted. Products with a thickness of more than 3 mm also carry information about the manufacturer and accuracy class .
When the drill is made of high-speed steel, it is marked in the form of the letter P. The remaining numbers with letters indicate how much and what component is in the alloy.
Suppose if the device says K6, that means six parts cobalt . When choosing long metal products, you should pay attention to the presence of such a component, because it improves the heat resistance of the product.
Signs of a dull metal drill
Most people continue to do necessary work with a dull tool until it breaks. As a result, they have to throw it away and buy a new one.
This happens because inexperienced craftsmen simply do not know how to sharpen drills. You can even restore a dull tool yourself, using tools available in any workshop.
Drilling should only be done with a sharpened product. If, when creating a hole, you hear a creaking sound in the place where the drill comes into contact with the metal, it means that it has become dull.
In this case, the tool will rub strongly against the steel, rotate and generate heat during operation. It’s better not to wait for the device to break, but to move on to sharpening a metal drill with your own hands.
How to sharpen a product at home
Home craftsmen usually do not use large metal drills at home; the most popular sizes are 0.5-18 mm. Of course, it is best to do the work of sharpening such tools on a machine. If you don’t have such equipment, then a small sandpaper that everyone has in their garage will do.
In addition, to sharpen a drill for metal, you can use an attachment on an electric drill or grinder . But before work, it is necessary to firmly fix the power tool on a flat surface. With their help you can make a rotating sandstone or sharpening disc.
You can make a device for sharpening drills with your own hands. When processing them, do not forget about safety precautions. It is imperative to carry out work wearing safety glasses to avoid injury.
Moreover, it is important to cool the product , otherwise the steel will lose strength, so you need to periodically lower the tool into a container with cold liquid. The water should be placed near a fixed power tool or sharpening machine.
Methods for sharpening drills for metal
Single-plane processing at home. This option is used when it is necessary to sharpen products no more than 3 mm.
The disadvantage of this sharpening is that the edge may chip during operation. This technique requires special care. Its essence is that the drill is applied to the circle and moves parallel to the working surface .
Sleeve or two-plane sharpening
This option is widely used by craftsmen to sharpen products. In this case, special bushings are used. First of all, you need to take the drill in your left hand by the working surface, then you should bring it to the fence cone, holding the device by the tail with your right hand.
The cutting edge of the product will be pressed against the end of the grinding wheel and, as a result, the drill will rotate around its own axis with the help of your right hand. In this way the back surface of the tool will be sharpened.
the correct angle when rotating the tool , formed between the end of the grinding stone and its inclination. It is for this purpose that special bushings are used to maintain the sharpening angle of the metal drill.
Conical sharpening
When you start sharpening twist drills with your own hands, first they process the back part, and then the cutting part. The work is carried out as follows:
- First of all, the surface of the device must be pressed against the grinding wheel or stone so that there are no gaps left.
- When sharpening, the angle must be kept the same at all times.
- It is necessary to pay attention to the tip of the product from the side: if the back surface is processed correctly, an even cone will be visible.
- Then you can proceed to sharpening the cutting edge with your own hands, while strictly observing the angle.
Using attachments for sharpening metal drills
This convenient method involves the use of special devices for sharpening products. The advantages of this method include ease of use and versatility . This device has a cylindrical shape.
It contains, on the one hand, a connecting unit, with the help of which the attachment is put on the drill spindle, and on the other, there are recesses for installing drills of a certain width. To process it, you need to insert the product into the hole, after which all that remains is to set the device in motion with the drill motor and maintain the sharpening angle.
Finishing after sharpening the drill
Without finishing the product, it will not be possible to eliminate roughness and achieve a smooth surface. In addition, drills that are subjected to finishing acquire wear resistance .
It is advisable to perform it with grinding wheels made of green silicon carbide . When making adjustments, it is important to maintain the symmetry of the axes. To avoid mistakes, it is better to check the correct sharpening of the drill angle with a template , which you can make yourself from the following materials:
Sheets of them should have a thickness of approximately 1 mm. Steel products are the most durable. Using the template, you can find out the length of the edges for cutting, as well as the angle between the jumper and the cutting part. It should be done before starting to use a new tool in order to transfer the required angles from the last one.
The easiest way to determine the correctness of the point is to carry out test drilling . When the cutting feathers are sharpened unevenly, in the less loaded part, chips will come out of the hole in small quantities. Sometimes it flies out through only one recess. Moreover, the diameter of the excavation made may exceed the thickness of the drill.
After sharpening a drill for metal, you need to pay attention to its symmetry. To make sure that the work was done correctly, you will need a regular drill . Using this tool, they drill into plastic and then check which side will produce more chips. It is this edge that will need to be refined.
Rules for storing new and sharpened products
When carrying and storing metal drills, you must ensure that they do not rub against each other. Remember that when removing the device from the general box, the cutting working edges will become dull on adjacent products.
Therefore, it is better to make individual sleeves or holes to store them in a vertical position. On top of that, it is recommended to sign the dimensions so that searching for a drill of the required size does not take much time. Of course, it is necessary to control the humidity in the room to avoid corrosion of products.
Recommendations for sharpening metal drills
Spiral products should be processed along the trailing edges. They should turn out exactly the same after work.
Moreover, this is not so easy to do, especially in manual mode, since it is necessary to maintain a certain shape and angle of the tool during sharpening.
Before you start sharpening a cutting tool, it is advisable to practice first on non-working products. It is also worth considering the fact that the drilling is performed by the side edges of the device.
Sharpening is carried out to return the cutting part of the product to its factory shape. When working, you should adhere to the basic rule for sharpening tools with tips made of various alloys: the harder the material of the drill being processed, the lower the sharpening speed.
Source: https://instrument.guru/osnastka/kak-pravilno-zatochit-sverlo-po-metallu-sposoby-i-video.html
How to sharpen a metal drill using different tools
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.
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.
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.
- 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.
- 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.
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:
- 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.
- 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.
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.
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.
https://www.youtube.com/watch?v=wY2X2IkNmf8
If a cone drill becomes dull in a limited area, then sharpening should be done without going beyond the damaged area.
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.
Conclusion
It’s not difficult to learn how to sharpen metal drills yourself.
- For small volumes, it is enough to purchase a high-quality file and carry out the process manually.
- 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.
(1 5,00 out of 5)
Source: https://plavitmetall.ru/oborudovanie/kak-zatochit-sverlo.html
Sharpening drills for metal: how to properly sharpen a drill with your own hands, video tips
There is probably no need to prove that any tool, including metal drills, has one unpleasant property - becoming dull during operation. Moreover, the speed of this process directly depends on the frequency of use of the drill and the volume of work performed by it.
Very often a person does not pay attention to this until the drill completely becomes unusable, after which it is simply thrown away, which is extremely wasteful. And this happens for the simple reason that not many people know how to properly sharpen drills for metal, despite the fact that all the work can be done independently, with improvised tools that can always be found in the workshop of the real owner.
How can you tell if a drill bit has become dull?
very sharp tools can be used to process metal . If during the process of drilling a hole you hear a not very pleasant grinding sound in the place where the drill touches the metal, then this is the first sign that the tool requires sharpening. If such an unpleasant sound appears, it is advisable to stop all work.
If this is neglected, then during rotation the drill will begin to generate a lot of heat, which, together with friction, will lead to accelerated wear of the tool.
Typically, craftsmen use drills of small diameter up to 16 mm for household needs. Naturally, it is more convenient to sharpen them using special equipment, but the cost of such devices for everyday use is unreasonably high and therefore they are purchased extremely rarely. However, in the pantry or garage of a zealous owner there is always a device that can be used to sharpen a tool:
- a sharpening glass with a wheel made of abrasive material;
- Sander;
- electric drill with a special attachment.
Any other tool on which you can attach a sharpening stone and set it in rotation is also suitable for sharpening a drill for metal. However, it is necessary that such a device provides a rotation speed of at least 1500 rpm.
Preparatory stage before sharpening
Before you start sharpening a tool, you need to prepare eye protection glasses and gloves to avoid damaging your hands, as well as a jar of plain water. There is probably no point in explaining the importance of safety precautions, since human health comes first.
During operation, microscopic metal particles , sparks and grains of the abrasive wheel can fly away in a chaotic manner. If exposed areas of the body are not protected, metal shavings and dust can penetrate the skin. But unprotected eyes are especially dangerous if they get into them, as any foreign body can cause serious health problems.
In turn, a jar of water will be needed to cool the drill being sharpened, since during the friction of the surfaces of the sharpener and the tool, a large release of thermal energy occurs. If timely cooling of the drill is neglected, it will overheat and during its intended use it can quickly break or become dull again.
Technological sequence of sharpening
Naturally, simply preparing protective equipment and a sharpening machine is far from enough. You cannot start working without familiarizing yourself with the technology of sharpening drills, for which it is advisable to watch the video. Even though the procedure itself is not too complicated, however, it requires strict adherence to the sequence of work.
In addition, you need to know how to sharpen different drills. This can be determined by the shape given to the cutting edges of the device. Today, experts are considering single-plane, two-plane, conical, cylindrical and helical methods of tool sharpening.
To determine the quality of sharpening of the drill, it is necessary to carefully examine it after completion of the work. The main factors that indicate that the instrument has become sharp are the following:
- upon completion of sharpening, the cutting edge of the drill must remain symmetrical with respect to its axis;
- adjacent cutting edges must remain equal in length relative to the central axis;
- the parameters for inclination of the angle of the pointed edges should also remain the same.
Sharpening the drill should start from the back surface of the tool and continue in accordance with a certain sequence.
- The rear edge of the cutting edge is pressed as tightly as possible against the sharpening surface. It is very important to maintain the initially set angle at all times.
- Without any skills, the procedure may not work the first time. Therefore, you need to be prepared to make several attempts.
- After each attempt, it is important to carefully examine the shape of the drill.
- Work should continue until the back surface of the tool is given the correct conical shape.
Only after the required shape has been obtained can you proceed to sharpening the cutting surface. When carrying out work, it is necessary to ensure that the sharpening of each pen is the same. Maintaining the correct sharpening angle is of great importance.
In the case of the single-plane sharpening method, the back surface is processed in one plane while maintaining an exact angle within 28–30 degrees . This method is considered one of the simplest and is used for tools with a cross-section of less than 3 mm. However, to fully understand the process, it is advisable to watch a video on how to properly sharpen a drill.
When performing work using this method, the drill is pressed at a set angle to the surface of the grinding wheel. During the sharpening process, the tool is moved without turning it over. This can often cause the cutting edge to crumble, especially if low-quality metal was used to make the drill.
To sharpen the cutting edge of a tool with a large cross-section, use a conical sharpening. This option is more complicated than those discussed earlier and therefore you need to familiarize yourself with the video, and then adhere to certain stages of work .
- The working part of the tool is taken in the left hand, and the tail end in the right hand. The working part must be kept as close as possible to the intake cone.
- Without changing the position, the drill is pressed with the cutting part and the rear surface to the end part of the grinding wheel.
- With the right hand, in which the tail edge of the instrument is held, rocking movements are performed so that a cone shape is formed on the side of the rear edge.
- After one feather has been sharpened, they move on to the second, repeating the entire process exactly.
- An important nuance of this procedure is that the drill cannot be torn off the surface of the grinding wheel.
There is another method of conical sharpening . To do this, the drill is also taken in the left hand from the side of the cutting edge, and in the right hand at the opposite end. But only the working part of the tool is pressed against the grinding wheel. With smooth movements, without leaving the sharpener, the drill is rotated around its axis, thereby uniformly sharpening the back surface of the tool.
Nuances of drill sharpening that you need to know
When carrying out work, it is important to try to maintain the shape of the tool that was given to it at the factory. Thanks to this, the correct angle is maintained. Conical sharpening is used mainly for drills with a cross-section of up to 10 mm. For larger tools, additional sharpening is required.
During the sharpening process, the size of the front and rear corners , and the angle of the working edge will increase. This increases the service life of the tool and reduces the width of the transverse edge, which does not take part in drilling.
In industrial conditions, after the tool is sharpened, finishing is performed. This event allows you to get rid of small nicks left after the main process. Thanks to this, the drill is less subject to wear. Therefore, if possible, it is better not to neglect finishing.
Figuring out how to properly sharpen metal drills is not that difficult, especially if you watch a video of the work being carried out. When doing all the work yourself, a person must be patient, since not everything always works out the first time. If you don’t have the patience and desire to sharpen the tool yourself, you can turn to specialists for help or simply purchase a new drill.
Source: https://stanok.guru/metalloobrabotka/sverlenie-otverstiy/kak-zatochit-sverlo-po-metallu-video-pravilnoy-zatochki.html
How to sharpen a metal drill at home
High-quality processing of materials such as metal and stone is impossible without the use of drills made of good materials, the geometry of the cutting part of which matches the required values. During operation, any, even the most durable drill, sooner or later wears out, losing the sharpness of the working surface. In such a situation, you need to decide whether to purchase new material, or look for information on how to sharpen a drill for metal.
Drill wear
Improper storage of the tool leads to the blades hitting each other, the adhesion of particles of the surfaces being processed and general contamination of the spiral. This factor negatively affects the service life of drilling tools, so it is recommended to store them in special cases and stands.
In addition to storage conditions, wear life depends on the purpose of the tool and the surface it processes. For example, drills designed for working with wood retain their working surface for several years due to the fact that wood is a relatively soft material.
Due to the fact that metal is a harder and more durable material, drills for working with it wear out much faster. Working with a blunt tool is unacceptable, since the holes will take longer, be more difficult to make, and will not turn out smooth.
The drill itself will become very hot, causing further wear to occur even faster and will certainly lead to the tool breaking. In addition, a breakage is often accompanied by the scattering of small fragments at high speed, which can lead to various injuries.
Signs that a drilling tool has become dull include:
- Creaks and other non-standard sounds made during operation;
- Strong heating of the tool;
- Low quality of created holes.
Working with a dull drill is difficult, often impossible. In addition to the fact that it does not drill the workpiece, the use of a worn drilling tool threatens to break it, which often leads to damage to the workpiece and to difficulties in removing the broken part of the tool stuck inside the surface.
In order to extend the life of the drilling tool and return the correct geometric surface, a procedure such as sharpening is performed. Any craftsman who often works with a drill should know how to properly sharpen drill bits for metal.
Safety precautions
The work described below is hazardous, so a certain set of rules must be followed:
- The machine must have a protective casing and screen that protect the worker from flying sparks and dust.
- Before turning on the machine, you need to make sure that the sanding wheel is securely fixed.
- Sharpening cannot be done by weight; you need to rest the tool on a tool rest.
- If the drill is broken, it can shatter into small fragments; in addition, during the work a lot of abrasive dust is produced and sheaves of sparks are cut out. Taking this into account, all work should be carried out wearing protective glasses and a mask.
Source: https://pochini.guru/sovety-mastera/kak-zatochit-sverlo-po-metallu
How to properly sharpen a metal drill with your own hands - detailed instructions
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://ismith.ru/tools/zatochka-sverla-po-metallu/
Sharpening a metal drill with your own hands. fixture and video – Tool Master
Metal drills are always hardened, but the products may become dull over time. Naturally, this is not a reason to throw them away. If you wish, you can sharpen the drill yourself using professional equipment or homemade devices.
Main types of sharpening
Experienced craftsmen know that sharpening a drill for metal varies depending on the diameter and specific application .
- Single-plane sharpening is designed for drills with a maximum diameter of 3 mm. During the work process, it is possible that the edges may “paint”, so you need to be very careful. To properly sharpen the product, it should be applied to the circle and moved parallel to the surface.
- The conical procedure is intended for larger metal cutting tools. In this case, the tool must be held with both hands, performing sequential sharpening.
- Finishing is carried out after finishing sharpening. Thanks to this procedure, it is possible to polish the cutting edge and eliminate even the smallest nicks.
Types of sharpening machines
To sharpen a drill with your own hands correctly, you need to use the appropriate machines. Such devices are divided into 2 groups .
- Industrial equipment has significant power. It can be used to sharpen drills with a diameter of 20 mm or more. These machines are installed at large enterprises, and sharpening is carried out in semi-automatic or fully automatic mode.
- Household machines are designed for use at home. They are also used in small production. Such equipment is characterized by mobility, average power and compact size.
Recommendations for choosing a household machine
If you are interested in the question of how to sharpen a drill for metal, then be sure to purchase the appropriate machine. An inexpensive model with average power is suitable for home use. It will allow you to sharpen small drills for metal.
Naturally, when purchasing, you need to pay attention to the noise level , as well as the design of the model. The best option would be a simple machine, because choosing the necessary parts for it will not be difficult.
It is necessary to buy such devices only in specialized places, since a technical passport is included in the kit. Moreover, you will be given a warranty card.
Using machines at home
As mentioned earlier, it is advisable to use household machines at home. With their help, it is possible to sharpen various types of drills. It is important to remember that for some varieties you will have to purchase the appropriate circles.
To sharpen a drill yourself, you should give preference to a machine equipped with a universal chuck. It allows you to clamp elements of various diameters.
Often included are:
The most popular equipment is from Drill Doctor and GS. Similar products are designed for sharpening drills with a diameter of 2–13 mm and 14–34 mm. Unfortunately, this equipment does not allow sharpening very thin drills. For this purpose you will have to purchase a special machine.
All equipment designed for sharpening drills at home has a number of advantages:
- possibility of working from the mains;
- high performance;
- ease of use;
- functionality;
- sharpening accuracy;
- affordable price;
- compact dimensions;
- light weight;
- convenient control system, thanks to which you can adjust the intensity of sharpening and its speed.
Homemade sharpening devices
If you do not have the appropriate machine, you can sharpen it using other devices. We are talking about an electric drill or homemade equipment created according to a drawing . It's best to give preference to the second option, otherwise you may ruin a lot of drills before you master proper sharpening.
You can even create a suitable device with your own hands from wood. So, a beam with holes corresponding to the diameter of the drills is fixed on a horizontal surface. The holes mentioned above are made at a slight angle to obtain the required sharpening angle.
Some craftsmen prefer an electric drill equipped with appropriate attachments. Naturally, the range of such elements is small , which complicates sharpening with your own hands. As a rule, a stone and a leash are included with the nozzles. If you plan to sharpen drill bits using a specific drill, you should immediately shorten the driver.
If you wish, you can make a similar attachment for a drill yourself, following the recommendations given in the corresponding video. Such devices must be equipped with fasteners for fixing the drill.
Features of the sharpening process
If this is your first time deciding to sharpen a part with your own hands, do the work in strict sequence .
- The back surface is treated first. So, press the drill tightly and constantly make sure that the sharpening angle remains the same. As a result of processing, the tip of the drill will resemble a regular cone.
- Next comes the turn of the cutting part.
- The last stage involves finishing the back surface. In this case, you must make sure that the size of the jumper is no more than 0.4 mm. Naturally, for a large metal drill, this parameter should be slightly larger.
If something doesn't work out right the first time, don't despair. It's best to start practicing with tools that you're unlikely to need. The main thing is to learn how to apply pressure correctly and maintain the angle. In this case, it is necessary to take into account the fact that the side parts of the drill, and not the tip, are responsible for drilling. Accordingly, the edges must be sharpened.
It is important to remember that the sharpening process produces small particles . Due to heating, they fly away in the form of sparks. It is for this reason that safety precautions must be followed. We are talking about using safety glasses and gloves. Also, when sharpening, you should make sure that the drill is securely fixed. Otherwise, it may accidentally fall out of your hands.
Recommendations for using the machine
If you decide to use an appropriate machine for sharpening, be sure to prepare your work area. In particular, we are talking about good lighting. You should also wear protective gloves and goggles .
- First of all, you should decide on the required sharpening angle.
- It is important to position yourself so that the grinding wheel is on the right.
- Alignment must be performed. To do this, take the working surface with your thumb and forefinger, and the second hand holds the tail edge.
- The metal drill must be rotated so that the cutting edge is parallel.
- An important point is the elimination of nicks.
- All movements should be performed in a certain sequence. So, the left hand is moved down to the left, and the right hand is moved clockwise.
To properly sharpen a drill with your own hands, you need to use a suitable device . This can be a household or industrial machine, as well as an electric drill with a special attachment. If you haven't tried sharpening a drill before, check out the corresponding video first.
Source: https://cs-important.ru/tehnika/zatochka-sverla-po-metallu-svoimi-rukami-prisposoblenie-i-video.html
How to sharpen a drill for metal and concrete with your own hands
It does not require special proof that the drill during operation loses the sharpness of the cutting part, that is, simply put, it becomes dull. A dull drill isn't a problem until it's needed.
Then it suddenly turns out that it is impossible to work with a worn or dull drill. We can only regret that the geometry and size of the drill were not restored in time.
This article will tell you how to sharpen a twist drill and a hard-tipped drill bit for drilling concrete.
You don’t have to worry about sharpening a wood drill; you can work with such a drill for many months and even years without any sharpening. Unfortunately, the same cannot be said about a metal drill, which must be sharp. That is, you can drill metal only with a sharp, well-sharpened drill.
Loss of drill sharpness is characterized by a sharp creak at the beginning of drilling. A drill that is not sharpened in time generates more heat and thus wears out even faster than a sharp one.
You can sharpen a drill on special machines or using devices. Naturally, if possible, it is preferable to do this on special equipment. But in a home workshop, as a rule, there are no such machines, so you have to use a regular electric sharpening machine with a stone.
Main components of a twist drill.
So, let's look at how to sharpen a drill for metal? The type of sharpening depends on the shape that should be given to the back surface of the drill and can be single-plane, two-plane, conical, cylindrical and helical.
The drill is sharpened along the back edges. Both teeth (feathers) of the drill should be sharpened exactly the same. It's not easy to do this manually. It is also not easy to manually maintain the desired shape of the back edge and the desired back angle.
1. Single-plane drill sharpening is characterized by the fact that the back surface of the pen is made in the form of a single plane. The rear angle ranges from 28-30°.
The drill is simply attached to the circle, so that the cutting part runs parallel to the circle and sharpening is carried out without rotating or moving the drill.
With such sharpening, the cutting edges of the drill may become chipped during drilling, which is a disadvantage of this sharpening method. This is the easiest method of manual sharpening, which can be used for a thin drill with a diameter of up to 3 mm.
2. Drills with a diameter of more than 3 mm are preferably sharpened conically. It is difficult to perform such sharpening manually without skills, but it is possible. The drill is taken with the left hand by the working part as close as possible to the fence cone, and with the right hand by the tail.
The drill is pressed against the end of the grinding stone by the cutting edge and the back surface, and is slightly rocked with the right hand, creating a conical surface on the back feather edge. During sharpening, the drill does not come off the stone, hand movements are slow and smooth.
For the second pen everything is repeated in the same way.
Move the drill with its cutting edge to the grinding wheel.
We swing the drill down and then up again.
When sharpening, you should try to maintain the original shape of the factory surface of the rear part as much as possible in order to maintain the desired rear angles. If sharpening is done correctly, then it is quite sufficient for drills with a diameter of up to 10 mm. For diameters above 10 mm, this sharpening can be improved by sharpening the front surface, as shown in the photo:
Front surface point.
What is the point of a point? By reducing the rake angle and increasing the cutting edge angle, chipping resistance increases, which increases drill life. In addition, the width of the transverse edge becomes smaller. The transverse edge does not drill, but scrapes the metal in the central part of the hole. The second picture clearly shows that here it is shortened, which makes drilling easier.
For drills with a selected small clearance angle, you can further sharpen the flank. In this case, the drill rubs less in the drill hole with its back surface. See photo:
Rear surface undercut.
In production conditions, after sharpening, as a rule, finishing is done, which smoothes the surface, removing small nicks. A drill that has been fine-tuned wears out less than a simply sharpened drill. If possible, fine-tuning should be done.
For finishing, you need to use grinding round stones made of green silicon carbide (grade 63C, grit 5-6, hardness M3-SM1) on a bakelite bond, as well as wheels made of CBN LO (grit 6-8) on a bakelite bond.
Below we present to your attention an excellent selection of training videos by watching which you will definitely be able to sharpen your drills.
How to sharpen a tipped pobedite drill bit
A pobedite drill bit can also become dull. A dull drill overheats during operation, drills poorly and makes a loud squealing sound. Of course, you can change the drill by buying a new one, but it’s better to save money and sharpen it yourself.
To do this you will need a sharpening machine (electric sharpener) with a diamond stone and coolant. An ordinary emery stone is not suitable for sharpening a Pobedit drill. Before you start sharpening, make sure that it is possible in principle. To do this, measure the height of the cutting part of the drill.
When the height of the cutting part of the drill, i.e. soldering, is about 10 mm, sharpening is possible.
Don’t forget: the harder the material, the lower the sharpening speed should be. The angular speed (the number of rotations of the stone) when sharpening a pobedit drill should be reduced, regardless of which tool is used for sharpening.
Sharpening the drill is done by briefly touching the drill to the emery stone. A pobedit drill is sharpened quickly; as a rule, you only need to slightly correct the slick edges, so you should carefully monitor the process so as not to cut off excess from the working surface of the drill.
It is recommended to sharpen tipped drills in the same way as simple small-diameter drills, i.e. The back surface should be sharpened flat. In this case, the back surface should be sharpened as shown in the photo, grinding the drill down to the soldering point:
Sharpened drill bit with soldering.
It is advisable to sharpen the front surface. If the soldering has already been ground down to the very drill, then it is simply impossible to do without sharpening, since the soft metal extends to the cutting edge from the front surface. The front surface is simultaneously ground down so that the thickness of the soldering center becomes smaller.
Solder point on the front surface.
When sharpening the drill, try to be precise and carefully ensure that its cutting sides are the same size. If this cannot be achieved, then the offset center of the spine will certainly result in the drill hole being enlarged and uneven.
Regardless of the device on which sharpening is performed, it is necessary to control the ratio of the front and rear angles of the cutting edge in the direction of rotation. Another rule that should be followed in order to properly sharpen a drill for concrete: the harder the material, the greater the sharpening angle.
For victory it is 170 degrees.
During the sharpening process, the drill must not be allowed to heat up, because Cracks may appear and the carbide plates may peel off. In order to prevent this, you should periodically cool the drill with liquid. You can use regular water for cooling.
We invite you to watch a selection of videos on sharpening drills with pobedite tips.
Sharpening drill bits for hammer drills. Part 2
Source: https://srbu.ru/instrumenty-i-oborudovanie/68-kak-zatochit-sverlo.html