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
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
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.
https://www.youtube.com/watch?v=wY2X2IkNmf8
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 metal drill correctly
July 11, 2018
Each drill becomes dull during use, but there is no need to rush to throw it away. You can often return a drill to its working condition by sharpening the tool. In this text we will explain how to do this.
After reading this article, you will learn:
Compared to wood drills, metal drills grind much faster. If you already have some experience in drilling metal, then it will be easy to determine the condition of the drill by contact with the material or even by eye. If there is no such experience, you can see and identify the condition of the drill if one of the following occurs:
- You drill and hear the drill whistling and creaking;
- rapid heating of the instrument;
- the resulting holes look bad - with nicks and burrs;
- only one spiral groove produces chips, this may also mean that the sharpening is incorrect;
When working with a drill with a blunt tip, we put our health at risk, since such a drill easily breaks. At high speed, this threatens with fragments that fly in an uncertain direction. This should not be allowed under any circumstances, so do not delay in replacing or sharpening the tool. As soon as you notice the listed signs, take action.
How the drill works
In order to update the working part correctly, you need to understand what components the drill has:
- the working part is created by bringing together the groove and rear elements;
- front element under the working part;
- vault between parts at the back;
When using a drill, the tip of the drill, the arch and the edges at the back become more deteriorating. In this regard, repair of the drill occurs by straightening the edges at the back adjacent to the tip and crown of the drill.
But there are some subtleties here: in order to renew the surface of the drill and bring out a clear arch, the sharpening angles must be aligned with the sharpening angles must correspond to the parameters of the drill itself.
Compliance with these standards will allow the working part of the drill to be the first to align with the workpiece, this gives us the greatest return on the tool. The angle of the drill tip determines the length of the working part of the tool. If it is brought out correctly, then the chips will easily fall into the chute and be removed from it. Well, if the angle is sharp, then the area of the strip being removed will increase, the chute will become clogged with chips, and they will not be removed from the hole. Well, an angle that is too obtuse removes the benefit of the tool.
Drills differ in the raw materials used for them and their diameter. Drill parameters vary depending on the direction of the material. Metal drills are best processed at home.
Any drilling unit has two planes at the back, forming a cone at the end of the tool and a pair of cutting edges. If you place the drill on a plane, the edges will touch it, the part located behind them will be located away from them. It is located at a certain angle, which is called “back”. The run-off should approximately be 0.2 mm for each turn.
Correct sharpening angle, methods of operation
Different materials have their own sharpening angle.
- Hard steel – 140°;
- Stainless steel – 135°-140°;
- Deep drilling – 130°;
- Cast iron - double angle. Main – 118°, auxiliary – 90°;
- Aluminium, brass, bronze – 118°;
- Copper and alloys based on it – 100°.
To sharpen a drill, a sharpening machine is used; using a whetstone or sanding sheet is useless for this. To complete the job, you will need an abrasive wheel rotating at least 1400 per minute. The abrasive is selected with fine grain.
When the drill overheats, the metal loses its characteristics, so it is important to lean the drill against the sharpening machine for a short time, no more than 4 seconds. To avoid damaging the drills, periodically cool them in water.
First of all, choose a method for sharpening the working part of the tool . Here's what they are like:
- single-plane;
- two-plane;
- conical;
- cylindrical;
- screw.
In this article we will look at such common methods of drill sharpening as single-plane and conical.
First, grind the edge at the back. Remove a small layer so that no irregularities are noticeable on the surface. If there are dents up to 3 mm, you need to shorten the drill by the same amount.
While working, look at the symmetry of the working edge and the evenness of the jumper. Normally, it is located clearly between the working edges.
A drill up to 3.5 mm is sharpened using method 1. When the back part is set to the correct configuration, it is brought to the abrasive at an angle of twenty-five to thirty degrees.
Do not rotate the drill or change its angle. Otherwise, the edge will not be perfectly smooth. In addition, when unrolling the drill, some of the edge material may crumble out of it.
Since the drill bit being sharpened has a small diameter, it is sharpened in one go and does not overheat.
Take a look at the very end of the drill - the converging planes should be commensurate with the same processing angle.
Check the angle according to the template. You cannot straighten the edge if the job was not successful on the first try; you will have to sharpen it again.
The conical processing method is completely different from the single-plane method described above. The tool is held with both hands and when the working edge comes into contact with the abrasive plane, the drill begins to rotate along the back side and forms a cone.
With this method, you cannot tear the tool off the sandpaper. Each approach starts from the working edge and ends with a full turn to the end of the back surface.
After each processing step, check the corners of the drill with the template.
Large drills cannot be machined using the flat method, as this will cause the drill to overheat and the chips will not be removed from the hole.
A little about repairing concrete drills
The listed methods for sharpening drills can be applied to drills for wood and metal. But Victory drills can also easily become unusable. The signs of a Pobedit drill being unusable are the same as those of a metal drill - it starts whistling, drills worse, heats up wildly, and a terrible whistling sound occurs. The principles of sharpening a Pobedit drill are the same as for metal drills, but there are some peculiarities that need to be considered.
It all starts with measuring the height of the cutting surface of the drill. Sharpen the drill only when its height is at least 8-10 mm. If the height of the working part is lower, you will not be able to get a good result - purchase a new tool. To perform the next step, buy a disc with diamond abrasive. At the same time, the special tip of the Pobedit drill does not withstand critical high temperatures. To avoid damaging the drill, adjust it at low speeds.
When sharpening a pobedite tool according to the rules, first remove the side edges of the cutting tool. They wear off first of all when you work on concrete. Please note that the soldering must be adjusted at ninety degrees. Secondly, work on the back edges, right up to the soldering. If the soldering has already been worn down to the steel, then it is necessary to sharpen the front part of the drill.
When sharpening a drill from Pobedit, in order not to overheat the tool, cool it with water or machine oil.
When sharpening Pobedit drills, it is important to maintain symmetry of the edges. It is important that the cutting sides are the same size. If the center of the axis is shifted, the efficiency of the drill may decrease, not to mention the holes will be ragged. It is important to remember: the sharper the angle at the apex, the harder the material of the tip. The recommended sharpening angle for pobedit soldering is 170 degrees.
To work with drills you need to be able to process the jumper. It is difficult to achieve the desired level of processing on a grinding machine. Therefore, this should be done as follows: the jumper and rear edges are drawn out at the edge of the circle, using a slow speed.
The tool is in contact with the sharpener for a short period of time. Then it is taken to the side, turned 180 degrees and again pressed against the abrasive.
After heating the metal, the drill should be dipped in water, otherwise the tool will lose its properties.
After sharpening is complete, check how symmetrical it is. To do this, you can conduct such a test. A machined drill is inserted into the drill, and a felt-tip pen is brought to the machined edge. The drill is turned on at low speed, the drill is covered with a marker line. If there is a larger line from the felt-tip pen on one side than on the other, then it needs to be sharpened.
Source: https://viratools.ru/blog/1287/
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.
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
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 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
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 sharpen metal drills correctly?
Hi all! Many of us have encountered problems with dull drill bits when working with hard materials. In this review, we will look at how to properly sharpen metal drills to restore their performance.
Preparing tools
To properly sharpen a drill, you will need:
- a sharpening machine or its substitute (grinder with an abrasive wheel, etc.) and calipers;
- a stencil for checking the sharpening of the drill (you can make it yourself);
- a container with water or machine oil (to cool the drill during sharpening);
- marker, scrap metal corner with shelf 30 - 40 mm + small clamp;
- a circle of soft stone for finishing cutting edges, safety glasses or a mask.
Attention: according to safety regulations, gloves are not used when working on sharpening equipment.
Preparatory stage
In order for the drill to effectively cope with its functions, it is important to create the correct angle at its tip. The angle at the tip of the drill is formed by the cutting edges; its value is selected depending on the material to be worked with:
- for steel, cast iron, hard bronze - 116° - 118°;
- for brass and soft bronze - 120° - 130°;
- for red copper - 125°;
- for aluminum - 140°.
For ease of sharpening, it is recommended to make a template from thin metal, which is applied to the side of the drill and checks the angle between its axis and the cutting edge - the value of this angle is equal to ½ the angle at the tip.
To sharpen drills, of course, it is best to use a sharpening machine equipped with a tool rest. If you don't have a machine, you can use portable tools with an abrasive wheel.
When working with an angle grinder, it is important that the device is securely fixed, which is quite difficult to do. With a gap of a millimeter from the working surface of the abrasive wheel there should be a securely fixed working platform for support, guide and hands holding the drill. Otherwise, it is almost impossible to sharpen correctly. Using a grinder, you can only sharpen thin drills, otherwise there is a high risk of injury.
Drills of the smallest diameter can be sharpened by hand using a flat file.
Drill sharpening
The first task is to make the back surfaces level and at the same slope. To correctly orient the drill when sharpening, use a marker to mark a line on the abrasive wheel’s support at an angle to the working surface of the wheel, corresponding to the angle between the cutting edge and the axis of the drill (half the angle at the apex). At home, they usually simplify the task and place the drill at an angle of 60°.
The drill rests on the index finger (or fingers, if the diameter is large) resting on the tool rest. The drill should be positioned with its side parallel to the marked reference line. Press it on top with the thumb of the same hand.
The second hand holds the shank and controls the movement of the drill in all planes, fixing it in the desired position. The degree of pressure of the drill to the circle is regulated by both hands. You should not squeeze or strain your fingers too much.
The drill must be held horizontally; the shank can be lowered below the cutting part, but in no case vice versa.
Source: https://postroju-dom.ru/stroitelnye-sovety/234-kak-pravilno-zatachivat-sverla-po-metallu
How to instantly sharpen drill bits yourself: useful tips
Drills can be very different, however, most often craftsmen give preference to those that can help in working with even the most durable materials. Anyone can understand that they need sharpening. To do this, just start the work process.
How to understand that a drill needs sharpening
If the drill has become too dull, then this will be evident at least from the result: it will not be possible to make a hole. Despite the fact that all modern drills are made from special grades of steel and are also subjected to a procedure such as hardening, over time they still become dull.
IMPORTANT! A responsible master always pays attention to the condition of the tool even before he starts work. If it seems too dull, then this is not a reason to throw it away, because everyone can restore its functionality with their own hands. You need to use a simple sharpening machine, which is also called an electric sander. This device will allow you to correct the situation and solve all problems as quickly as possible.
You also need to take into account that sharpening can have different sizes and depends both on the technical characteristics of the product (diameter) and on the characteristics of its use. For example, some options are needed for working with soft metals, while others are needed for working with hard metals. It is quite natural that they can differ greatly from each other, which also needs to be taken into account before you start sharpening.
To summarize, we can say that even someone who does not have much experience can understand the need for sharpening. This is a feasible task even for those who are picking up a drill for the first time. You just need to carefully observe the process. If it goes very tightly, then most likely the problem lies in insufficient sharpening.
Typically, the need to sharpen a drill arises after prolonged work with particularly hard and durable materials.
Set drill sharpening parameters
In order to quickly restore the geometric parameters of the product, you need to act slowly and carefully, otherwise it will break.
During sharpening, the edge should be parallel to the working surface of the sharpener axis. Otherwise, you will not be able to achieve success. Every master should know about this. When sharpening, you need to act gradually. If you rush, you can easily break the product or render it inoperable, even on a new and expensive machine. This is possible even if we are talking about an experienced master.
The most important parameters that need to be taken into account during sharpening are the total length of the cutting edges, as well as the angle of the tool. If you ignore these parameters, then the most serious problems may arise.
What you need to sharpen a drill at home
You need to purchase an emery machine, as well as a grinding wheel. This will be quite enough. If you buy additional tools, the process will become even simpler, however, some tools are too expensive, so it is important to determine in advance the acceptable cost of each individual tool. Otherwise, the cost of home sharpening will be too high and it will be more profitable to turn to professionals who have extensive experience.
It is almost impossible to quickly process metal without tools, which is why it is so important to acquire all the equipment on time. With their help, you can significantly speed up the procedure and achieve excellent results in an extremely short period of time. This is especially important if you urgently need to make a hole in a hard surface.
IMPORTANT INFORMATION! All drills that are used for working with metal have to be sharpened quite often. Options used for wood processing can boast a much longer “lifespan”. The thing is that wood is a relatively soft material that does not require too expensive drills.
It can be handled even by those who do not have much experience. With metal, everything is completely different, which is why it is so important to know in advance what exactly you need to sharpen the drill for. Some craftsmen use blunt products when drilling a metal surface.
They end up spending a lot of time on just one small hole, which is why it's important to prepare in advance.
How to sharpen a concrete drill yourself
Many people are very afraid of the sharpening process. They think it's too difficult. Indeed, self-sharpening is associated with a number of difficulties, so it often becomes impossible for an inexperienced craftsman. Most often the problem affects people whose eyesight is too poor.
In this case, it is best to purchase a machine for home sharpening. You can find relatively inexpensive machines made in China. You just need to follow the instructions that come with the machine. You can also sharpen a drill using a regular grinder, but this method is only suitable for experienced craftsmen who are well versed in repairs and know exactly what needs to be done.
Do-it-yourself metal drill sharpening
Sharpening a metal product is a particularly complex process. If the drill is dull, then further work makes no sense. It will lose its surface sharpness too quickly. Only after you have managed to find a high-quality tool can you start sharpening.
To do this, you need to find a special machine and make sure that the angles at which the drill is located in relation to the plane of the material are correct. You can find out the correct angles from the instructions for the machine. If such instructions are not at hand, then you will have to study the Internet and try to find instructions that will indicate all the useful information.
When choosing a machine, it is recommended to consider a number of factors. It is best to read reviews on specialized resources and study customer reviews. Then no problems will definitely arise.
Sharpening a tipped pobedite drill
Every modern tipped drill, despite its strength, will sooner or later become dull. In order to restore the previous efficiency, you will have to use a diamond wheel. Before you start the sharpening process, you need to make sure that the total height of the part (cutting) is at least 1 cm. All work must be done at the lowest speed. This is necessary so as not to accidentally break the tool.
Another tip: you need to grind the working surface of the drill before soldering. It is recommended to grind even the front surface. This is especially important if the plate has worn down almost to the drill. The front surface must be processed in such a way that the level of soldering thickness becomes much smaller.
Despite numerous difficulties, it is impossible to do without sharpening. A drill that is too dull will not allow you to perform simple work with concrete or metal, which is especially important during repair or construction work. Sharpening for the first time can be challenging, but over time the process will seem fairly simple. You need to be careful and not make too sudden movements. Then the instrument will not break and will serve its owner for another year.
Useful tips from professionals
- A drill is a technically complex tool that requires the sharpest possible drill bits. Otherwise, it will be impossible to make at least one hole in metal, concrete or wood. It is recommended to use special drill attachments that will facilitate this process and allow you to maintain the sharpness of the drill for a very long time.
- It is recommended to carry out the sharpening process as often as possible.
Then you can get rid of unnecessary problems associated with lack of time, because many people find out that the drill is dull right before starting work.
- The type of metal that needs to be drilled affects the sharpening angle. If you forget about this, you will have to do all the work again, since the drill will very quickly become unusable.
- Proper storage will increase its service life.
You need to use stands and pencil cases.
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Source: https://setafi.com/bytovaya-tehnika/kak-momentalno-zatochit-svyorla-dlya-dreli-samomu/