On the modern market, you can find twist drills, flat and center models:
- spiral elements, according to their name, differ in the spiral shape of the edges;
- flat products are designed for making deep holes of large diameters;
- center drills are used to center elements.
All the presented types of drills become dull over time. Reducing the sharpness of the cutting element interferes with construction work. This means that the product needs to be restored.
To date, 5 types of drill sharpening have been developed. Each individual method corresponds to the type of material of the cutting element and the specifics of its work.
- “H”. this type of sharpening is universal. However, it is used when restoring drills with a maximum diameter of 12 mm.
- “NP”. in this case, sharpening of short crossbars is performed.
- “NPL”. a type of sharpening involves lengthening the transverse edge and width of the tape.
- “DP”. in the professional field, this type of sharpening is called “double”. In addition to the transverse edge, 4 more edges are formed in the form of broken lines.
- “DPL”. the description is similar to the 4th sharpening method, only the sharpening of the tape is added.
In industrial conditions, sharpening is carried out on specialized equipment in compliance with safety regulations. However, for household purposes, several other devices have been invented and developed:
- a mechanism equipped with a sharpening stone;
- machine connected to the mains;
- an angle grinder and a drill (however, they are used only if there are no strict requirements for the sharpening angle);
- sharpening tips for drills.
Each individual device offers a high level of performance, angle accuracy and ease of use. They have a very convenient control system that even an amateur can handle. Another additional advantage of the presented options for home devices is low cost and miniature size.
Ideally, you need to sharpen the drills with a grinder. However, in the absence of this equipment, you can only use the disc from it. The main thing is that the grain size of the emery wheel meets the requirements. The round emery should be fixed to a drill or sander. The use of an angle grinder is recommended only as a last resort.
It is important to note that there are multiple health risks associated with sharpening cutting elements. Therefore, before starting work, you should protect your eyes by wearing special glasses. A bowl of cool water should be placed next to the drill to be sharpened, in which the cutting element will be cooled.
How to sharpen different drills?
According to experts, one should start an independent practice of sharpening drills with cutting products with a diameter of more than 10 mm. The sharpening angle for such elements is 120 degrees. After the procedure, the front of the drill should be symmetrical. If an error occurs during sharpening, it can be corrected immediately.
At some distance from the cutting edge, there is a so-called flank surface. It should be located within 1-1.5 mm relative to the cutting edge in the downward direction.
Further, it is proposed to get acquainted in more detail with the theoretical side of the do-it-yourself sharpening process. First of all, you need to do some preparation. On the surface of the grindstone, draw a line parallel to the rotation of the axis with a black felt-tip pen.
Next, you need to place the drill correctly. It must be kept clearly horizontally. In this case, the markings made with a felt-tip pen will be located slightly above the axis of rotation. Thus, the longitudinal part of the tool, located horizontally, will be turned to the left by approximately 30 degrees, which will ensure that the required sharpening angle is obtained.
Now you can move from theory to practice. A drill with a blunt tip is taken. Next, you need to find the correct position of the tool. Initially, one side is sharpened, and then the other. In no case should you be in a hurry. The work must proceed with the utmost care. If suddenly the sharpened edge heats up and turns red, you need to dip the drill into a container of water. After cooling the cutting element, you can continue working.
Having finished sharpening the knocked-down drill, you need to check the result. For this, a drill is taken, a sharpened tool is inserted into the chuck. Then you can try to drill a steel surface that is 8 mm thick. If the holes are drilled without difficulty, then the sharpening process was correct.
In fact, there are many ways to sharpen cutting elements. And each separate method assumes processing of drills for different materials. For aluminum, copper and even stainless steel, twist drills are used, which are sharpened according to the universal and double “method”. Sharpening a drill for spot welding is done by an angle grinder. Small drills with a diameter of less than 4 mm are sharpened exclusively by hand. By the way, if necessary, you can sharpen the old drill for the cutter yourself.
Unfortunately, not everyone succeeds in sharpening a dull drill the first time with their own hands. But with a little patience, you will be able to achieve a positive result.
As mentioned earlier, before starting the sharpening of the drill, it is necessary to calculate the correct angle for the restoration of the cutting element. For the convenience of finding the correct indicator, a special table has been developed, where in the 1st column the degree of inclination with a digital value is indicated, and in the 2nd. the material intended for drilling.
Steel, cast iron, bronze
An incorrect turning angle will cause the drill and the power tool to heat up during operation. And the quality of the drilled hole decreases significantly.
Those who use the drill once a year do not notice that it loses its sharpness. But with this approach, at one point, it simply will not make a hole. And then you will have to make an independent decision. either purchase a new drill, or restore a blunt.
The very process of sharpening on professional equipment does not require human effort, which cannot be said about restoring sharpness with your own hands. However, before proceeding with a detailed acquaintance with the rules of sharpening and the intricacies of the process, it is necessary to find out the signs that the drill will soon become unusable:
- the cutting element is very hot;
- small metal shavings fly out from under the edge;
- the noise from the working drill becomes many times stronger.
Particular attention should be paid to the last feature. The friction between the blunt edge of twist drills and the surface to be drilled increases, resulting in unusually loud noise. In such a situation, it is necessary to immediately stop working, otherwise the cutting element will heat up, its structure will change, so it simply will not be possible to restore the drill.
Further, it is proposed to get acquainted with some rules and instructions of experienced craftsmen who are engaged in regular sharpening of blunt centering tips.
And what is remarkable, from the information offered, it becomes clear that you can restore the drill with your own hands.
Drill sharpening process requires special equipment. In this case, we are talking about grinding machines and attachments for drills and hammer drills. A sharpening machine is a device equipped with a sharpening stone. Drill and hammer drill bits have unusual tip shapes. Often in private houses there is a miniature sharpening machine, since this device can be used to sharpen not only drills.
The sharpening technology depends on the type of drill. Today, there are conical, screw, cylindrical, single-plane and double-plane cutting elements on sale. Each of the presented types of cutting elements requires a special approach to sharpening, but the common thing between them is that only the rear edges are sharpened.
It is very difficult to do it manually, but it is possible. Especially when it comes to small specimens. Small and thin drills are always sharpened by hand, thanks to which a person fills his hand in the sharpening skill and after a while can put in order cutting elements of large sizes.
Single-plane drills differ from their counterparts by the presence of only one plane. The angle of inclination of the sharpness according to the standard ranges from 28-30 degrees. It is this part that lends itself to restoration. This beveled plane is brought up to an inactive grindstone. If the stone rotates, chances are good that the drill will get the wrong angle. Two-plane drills are sharpened in a similar way. The only difference in the sharpening process is the need to process two planes.
It is important to be very careful when restoring tapered drills. The tapered shape of the edge must not be violated. That is why the drill needs to be brought to a rotating grindstone, press on the cutting element and use oscillatory movements to sharpen the cone. The main thing is not to remove the drill from the stone and carry out the entire procedure with one touch.
An important rule of thumb when sharpening drills is to maintain the shape of the edge. It is no secret that this is not possible in every case. Especially when it comes to sharpening drills with a diameter of 10 mm or less. However, for this type of cutting element, it is preferable to maintain only the clearance angle.
As for drills with a diameter greater than 10 mm, grinding professionals advise to sharpen not only the edges of the planes, taking into account the angle holding, but also the front planes, which significantly improves the technical characteristics of the structure. This sharpening will be more effective in drilling work.
Due to the correct sharpening of the rake plane, the angle of the cutting part of the drill becomes larger, which significantly increases the endurance of the metal element. In addition, the transverse length of the edge becomes smaller, due to which the product does not cut the hole, but scrapes.
After the sharpening procedure, it is necessary to fine-tune it. In simple terms, remove the burrs caused by the mechanical action of the grindstone. For factory sharpening, this procedure is extremely important. Thus, it is possible to increase the level of wear resistance of the cutting element. At home, fine-tuning is not always possible to do, however, if there are the necessary devices, you cannot skip this procedure.
For home finishing, it is necessary to use a silicon carbide or elbor stone. They can be purchased in any construction market. Silicon carbide stone is green in color. Ideally, you should use a copy of grade 63C with a grit index of 6 and a hardness of M3-CM1. If the choice fell on a stone from Elbor, it is necessary to take a specimen with a grain index in the range of 6-8. It is important to pay attention that the presented stones for finishing should be made on a bakelite bond.
Special attention should be paid to step drills. They can be purchased on the market as single items or as a kit. The diameter of the produced step drills ranges from 4 to 21 mm. Step drills are of high quality and wear resistance, but even these cutting element patterns become dull. And, unfortunately, the restoration of the tip of the drill is possible only in some models.
If we are talking about a victorious drill, use a diamond wheel for sharpening.
In concrete drills, only the rear surface is sharpened. For restoration, the two-plane or tapered method should be used.
First you need to familiarize yourself with the conical sharpening method. The cutting element is required to be inserted into the prism of the grinder, which moves around its axis. Next, configure the parameters. The axis of the taper should have an angle of 45 degrees to the axis of the drill. It remains only to activate the device and wait until the end of the work. The tapered method is used to create a sharp increase in the clearance angle of the cutting element.
It is recommended to use the screw method to automate the process. It is characterized by forward movements consistent with the rotation of the grinding wheel. Remarkably, this method allows you to simultaneously sharpen the front and rear corners of the cutting element.
All about sharpening drills
- Basic Rules
- Sharpening angle
- Tool requirements
- How to sharpen different drills?
Construction professionals constantly deal with different types of drills that become dull over time. Poor quality cutting elements become unusable after a few months. Expensive branded samples serve their owners for more than a dozen years. And it is their builders who do not want to lose, but send them to sharpen. In principle, this is the right decision, however, you have to pay a lot of money to restore the state of a blunt drill. And in order not to empty your wallet, you can use the recommendations for sharpening yourself.
Conical and single-plane sharpening
These are the two most common ways to create a back apex angle.
- A conical clearance angle is formed in drills of large diameter. from 3 mm and above. To do this, hold the product with two hands, press it against a grindstone on emery and gently shake it with equal pressure. Similarly, two teeth are sharpened.
- The single-plane clearance angle is suitable for small drills 1–3 mm in diameter. The teeth are ground in one plane parallel to the emery. In this case, the slope can be 28-30 degrees.
Sharpening on a grinding wheel
An emery machine equipped with a grinding wheel is a universal device. If available, sharpening drills will take a few minutes.
What do we have to do:
- Position the drill at a 60 degree angle to the plane of the grinding wheel. In this case, the cutting edge should take a horizontal position and be parallel to the circle.
- If the drill is large, badly damaged, worn out, you should first use a coarse sharpener for metal, and then a soft one. In other cases, only one wheel can be used. for fine sharpening.
- Place your left hand with the tool on the handrail. Secure the drill with your thumb. Grasp the shank with your right hand.
- Include emery. Slide in the drill bit carefully. Press the cutting edge against the surface of the wheel and gently move the tip upward while lowering the shank. Maintain a 60-degree angle while performing sliding movements and do not loosen the pressure.
- Rotate the drill 180 degrees. Place it in the same way (see item 1) and sharpen it (item 4). The main task is to make the back surfaces even and with the same slope.
- Continue to sharpen the tool evenly on both sides until the cutting edges are sharp.
- Check if the edges are symmetrical. Correct their length if necessary.
- Reduce the jumper if it is too wide. This will help reduce resistance when cutting metal.
The speed of rotation of the grinding wheel depends on the hardness of the material. The harder the drill, the slower it should rotate.
Stages of work
According to the rules, you need to sharpen in a utility room, in a garage or, in extreme cases, on a balcony. Under no circumstances should you do work in the kitchen. Metal shavings and dust will fly around the workplace. It is impossible for it to get into the eyes, digestive organs, respiratory tract. You should put on glasses, and after the end of sharpening, vacuum the room and do wet cleaning.
Drill sharpening consists of several stages:
- Grinding tool preparation.
- Determining the exact angle and method of sharpening.
- Sharpening. First, the rear surface of the drill is grinded, then the cutting edge is straightened and the bridge is reduced (if necessary).
- Lapping to smoothness.
When sharpening, make sure that the drill does not overheat. Otherwise, the risk of deformation increases. Place a container of machine oil (or, in extreme cases, water) next to it. After drilling each point, immerse the drill in the liquid for 2-3 minutes.
How to sharpen drills correctly. 3 easy ways
With constant use, the drills last 2-3 weeks. Considering that many of them are expensive, and it is not easy to find a good sharpener, many try to restore them on their own. How to sharpen drills? There are many different ways to sharpen. We will tell you about the simplest ones, which do not require expensive electrical equipment.
Determination of angle and shape
The main task when sharpening a drill is to restore the factory shape. Drills are flat, spiral, center, with one or more edges. Some are designed for wood, others for plastic, metal, copper, etc. According to the purpose of the cutting part, the correct shape is given.
Easy Way Sharpen Drill Bit Use Angle Grinder. FREEPLAN
The most popular is the twist drill for metal. It is used for drilling wood, metal of medium and low hardness, plastic. When sharpening such a tool, the apex angle of 118 degrees is maintained (if necessary, it can be changed by 30% up or down). Front angle is 20 degrees, rear angle is 10 degrees.
Angle grinder sharpening
Use an angle grinder only in extreme cases. It can cause injury if it is mobile. In order to avoid unpleasant situations, it is recommended that the tool be securely fixed on a plywood sheet or inserted into a vice. Also, amateurs make special devices for guiding and holding drills at a certain angle. They are attached to an angle grinder. The result is a convenient and efficient sharpening machine.
For sharpening, an abrasive wheel is installed on an angle grinder. The further course of work is exactly the same as when using a grinding machine:
- The drill is set at the desired angle to the abrasive disc.
- The back surface of one tooth is grinded, then the second.
- The length of the cutting edges is corrected.
- The jumper is being sharpened.
The angle grinder can only sharpen fine drills. Sharpening large diameter solid tools is likely to cause injury.
3 main rules
Before starting work, you should familiarize yourself with the structure of the drill. The tool consists of a shank and a working part, at the end of which there are elements involved in cutting metal or other material:
- two cutting edges,
- flank surfaces (areas behind cutting edges),
A sharpened drill looks like this:
- Two cutting edges are sharp and symmetrical to each other.
- The flanks are chamfered and located below the cutting edge. That is, there is a gap between the part to be drilled and the tip of the tool.
- The jumper is not too thick and is in the center.
In order to sharpen the drills properly, it is important to have good lighting in the room. A person must have good eyesight. If your vision is low or the instrument is shallow, you will need a magnifying glass (glasses with magnification).
Drill sharpening angle grinder
There is a sander in almost every home workshop, so the method will be one of the most budgetary.
In addition to an angle grinder with an installed grinding wheel, for work, you need to prepare a vice in which the drill will be held during sharpening. The room where the tool is debugged should be light so that you can control the process of removing metal from the cutting surface.
Debugging is carried out in the following sequence:
- the drill is installed in a vice in a vertical position;
- angle grinder removes part of the trailing edge to completely eliminate wear marks;
- 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. Repeating the removal of a small amount of metal from the working edge many times, it is possible to adjust the tool to the required angle.
For measurements, it is recommended to make a template from plastic, which will help control the magnitude of the sharpening angle.
It is more convenient and safer to work with the use of a grinding wheel and a special holding device.
You can sharpen a stepped drill using a regular file. The cutting edge of the product is sharpened at a right angle.
If the cone drill is dull in a limited area, then sharpening should be carried out without leaving the damaged area.
What signs indicate that it is time to sharpen the drill?
It is not recommended to start sharpening the cutting edge of this tool without an urgent need. Indeed, during this difficult procedure, you can spoil the product with one wrong move, and only a professional can fix such a defect. Therefore, you should start sharpening the cutting part of any tool only after it has really become dull.
Experienced craftsmen understand that it is time to sharpen the cutting surface of the drill, according to the following signs:
- during drilling, small chips fly instead of spiral shavings;
- the workpiece and drill quickly overheat;
- the process is accompanied by strong noise.
Each of these problems should be the reason for checking the sharpness of the tool, followed by its sharpening.
Employees of specialized centers working on expensive equipment will cope with the problem in a couple of minutes. However, even in a home workshop, you can solve this problem if you have sufficient skills and tools in the form of an “angle grinder”, sharpener or special attachments for an electric drill.
Unfortunately, it is hardly possible to sharpen a thin drill using mechanized methods, including drill bits. All work on the restoration of a small diameter product will need to be done manually.
The first attempt may fail, so you should first select an inexpensive thin drill in need of restoration and carry out the operation on it. You will also need a small diamond file and glasses with 4x magnification to work.
The process takes place in the following sequence:
- the drill is ground down by about 1 mm;
- a file is used to consistently sharpen the edges of the tool to the required angle.
The whole operation is performed “by eye”, it is important to use magnifying glasses and a powerful lighting device when working.
If the first attempt was unsuccessful, you should know that any skill can be developed only within a certain period of time. In case of failure, do not give up trying to learn a useful skill, like sharpening fine drills with your own hands.
I remembered how one figure from Moldova used an angle grinder to dismantle old windows and doors with a disc from a circular saw and even without a casing, the sight is not for the faint of heart how the disc begins to rotate with characteristic wriggles, well, if you think about the consequences “clamping” which, by the way, is quite real (everyone who was nearby immediately left the room where such a not decent lesson with words was conducted “he d”) to which he replied “and what are they all afraid of”?! so looking at this “adapt” fantasy starts to work))
Normally, only a person who can and knows how to do it on a regular circle can sharpen a drill on this, which means that he does not need this adaptation, and if you do not know how, then it will not help. Conclusion: can be attributed to useless inventions, and time wasted.
I wanted to write about it, but I was ashamed. Foreign is this language for him.
Also an angle grinder drill point) Holding in hands) It seems to be drilled.
This is a DANGEROUS setup. The rotation speed of the angle grinder wheel is 9000-11000 rpm, in this case the grinding wheel is grinded at the base, you can imagine what will happen at such revolutions if the wheel breaks. One more thing, the drill sticks with a finger, the drill can slip out and rest its tip against the thin section of the circle, and then the imagination turns on again what can happen at 10,000 rpm. There are special installations or a sharpener for sharpening drills.
I liked the idea. definitely bookmark!))
I would have one for sharpening a drill for spot welding) the price would not have been for him
The most important thing here is head work, and everything else is life experience.
If we could collect all the craftsmen, and give them all what they deserve, we would already live on other planets.
Forward to the heights of the universe!
And that the hands no longer hold or the eyes are crooked
My grandfather would have seen it, he would have killed the hell. So the circle is rotten.
That’s what I did. The idea was stolen from the Internet. From this device. It turned out like this. The sharpening angle is regulated. Sharpening goes from the bottom of the cutter to the top at an angle of 45 degrees.
angle grinder drills do not sharpen only with emery where the speed is small, respectively, and the stone is different there. ))
I totally disagree with you. You can sharpen, the main thing is to be careful and know how to sharpen. and will drill great.
At one time I was taught to sharpen drills, now it’s not a problem to sharpen on a sharpener or an angle grinder
Guys. Let’s have a drink? New Year is coming soon!
Kapets, also a disc upside down
Definitely KG / AM
Spam in the feed. people can get hurt from this.
Sometimes it is also the drill I cut on the cut-off wheel. But without any attachments. However, the angle grinder has a speed control to prevent the drill from burning.
In addition, I do not hold the drill in the same place, so that the disc does not end up regrinding.
On ordinary emery, it is also not advisable to constantly poke a drill into the same place. Well, one more will sharpen normally, but after the second a groove will appear. Always sharpen by hand and use the full width of the whetstone to keep it level.
There is / should be a roller cutter next to the stone usually.
And why is she to me, if I never have grooves on a stone?
It’s normal, but it seems that if you make such gadgets yourself, you are unlikely to sharpen your drills with them, wasting time assembling the adapters :).
But still interesting.
For example, I ask someone to hold the angle grinder, and sharpen
There are many letters. Sharpening is not correct.We look on YouTube.
so the sharpening is not correct, the end should not have a front cutting part at the same angle with the back, such a drill can only be melted, not drilled
This is bullshit, a right angle is not made on drills, without proper sharpening, they drill horseradish and a little. The idea was originally shit, it’s easier about a whetstone then.
And the fact that this is here only for advertising your YouTube channel, so generally turns the post into deliberate shit, akin to spam or information terrorism. As they said in the old days. KG / AM
I do not understand! why-when you can with your hands
Today I broke 5 drills. Yellow shit, but with a magnetic lock. your method is certainly dangerous, but if it is for emery, then it’s ok
You just have to write “manual how to make a disc burst for an angle grinder”. And to print. For fools. Let them be crippled.
I watched it to the end. I will upset you, a properly sharpened drill bit for steel gives long chips, or your speed is too high. This is called not drilling, but making holes. Maybe I’m too nitpicky, it’s just that my grandfather raised me from childhood in reverence for plumbing, and at one time I myself had the 4th category of ship repair locksmith. But most will do it anyway)).
I’m waiting for when they start making hands to hold the grinder when you cut what kind of metal 🙂
if you are here then yes. and I sneezed at you, this is my opinion on the statements on this site. Well, yes, for those advanced in cnc, he does everything for a person
I somehow don’t care about smug imbeciles who can only scream I I I, and pass off other people’s thoughts as their own, but they themselves don’t even know how to pick their nose.
Nice to meet you ciliate unicellular
The drills are sharpened on two stones. Larger. set “the form” and angle. On diamond (cup) lapping the cutting edge or “grinding”. Angle “attacks” not received. On an angle grinder, only the first stage of sharpening. The disc is inverted. /// For the accuracy of manufacturing, welding, stripping. excellent
Not many people have diamond discs, much less a sharpener with a higher speed for diamond discs. But people are learning.
I liked the idea.
But the question is not quite a record.
Spot welder? Homemade or store-bought. It is possible in more detail in a nutshell. thank!
Welding review on my channel
The angle is not quite right. The back of the cutting edge must not be flush with the front
Flank roughness and cutting edge quality are not considered. And on safety. questions.
Plus for the craving for design.
If there is emery, then the quality of sharpening on it will be higher than on the grinding wheel, even by hand.
The guy really does something with his own hands, but here I see from the comments that some turners and CNC specialists sharpen everything on sharpeners with their eyes closed and without electricity. Do not bother people with their I !
b. I then create yourself a site for losers without brains, you fool, or what life does not teach, or muscle memory is not developed in your brain
The guy really does something with his own hands, but here I see from the comments that some turners and CNC specialists sharpen everything on sharpeners with their eyes closed and without electricity. Do not bother people with their I !
Remember one thing, the entire book on safety is written in human blood! And such “benefits” instructions how to do it is not necessary.
But it didn’t say it was safe. And here there are a lot of unsafe things, and everyone chooses for himself what he needs and what lesson he wants to learn.
I won’t even argue. Everyone chooses the method of suicide. I also know how to work with an angle grinder and 230 m around the cleaners I bring the brake disc to the ideal. But I do not spread that people without experience would not repeat. And they were not killed. For 10 years they did not take out foundations for blueing on submarines.
If you have the skill of sharpening drills on NORMAL emery, then this pribluda is useless. And if there is no specified skill, then even more so. In addition, a cutting disc for sharpening a tool is of little use, and it is not safe to use the side surface of the disc.
I respect perseverance and an attempt to make the work easier, but, IMHO, the time spent on making the pribluda was much more useful to spend on training in sharpening drills on ordinary emery. Fifty trial sharpenings and a certain skill acquired.
It’s a sin, I myself sometimes grind the angle grinder tool, but only when there is nowhere to go.
And when the drill breaks, sharpen it on emery?)))
If they are vryatli at the root, and why not?
And when the drill breaks, sharpen it on emery?)))
Easily! Sharpened and repeatedly. And I sharpened quite large diameters, for example 16 mm. And on what else to sharpen a broken drill? Just with an angle grinder, a broken drill will have problems. Cutting off the place of fracture with a cutting disc, the drill is easy to overheat, followed by metal tempering.
A well sharpened drill should drill this profile in 5 seconds and without any lubricants. For work 5, but the drill itself is garbage, along the way for wood, it will not drill metal.
Modern drills have sufficient strength reserves to make straight holes in a wide variety of materials. However, during operation, the cutting edge of this complex tool can become dull rather quickly, which sharply reduces the efficiency of its use. Therefore, a drill intended for work on metal must be sharpened in a timely manner.
How to sharpen an angle grinder drill correctly
Sharpening metal tools allows them to fully restore their functionality. The operation can be performed using various accessories.
How to properly sharpen a drill for metal and not spoil the cutting surface of the product will be described in the publication.