On the Internet you can find a huge number of schemes for making devices with which you can sharpen drills. However, most often such schemes are very complex and the average person cannot understand them. You can, of course, try to sharpen the drills by hand on a sharpening machine, holding the tool at an angle of 60 degrees. However, even in this case it is very difficult to achieve perfect sharpening so that there is no displacement of the center. However, there is Alternative option- This is a homemade device for drill sharpening, made from door hinge. Anyone can make such a device.
Features and manufacturing process
The mechanism of the homemade sharpening device is based on the turning movement of a regular door hinge (you will need a hinge with a metal thickness of at least 3 mm). The lower part of the loop will be fixed to the tool rest, and the upper part will move the drill. In order to securely fix the lower part of the loop on the tool rest, you will need to weld a 25x25 mm corner, then drill a hole in it and cut a thread for an M6 bolt.
On next stage works need to be exhibited correct angle To sharpen the drill, I use for this a piece of steel angle, which must be welded to the loop, and an ordinary school ruler with a protractor. To check that the angle is set correctly, use a factory-sharpened drill - it should be in contact with the entire plane of the edge of the pen. Next, you will need to weld an M8 stud to the structure with a pre-prepared clamping nut made of 4 mm thick metal. The device is ready!
Drills must be of high quality and well sharpened in work professional master. In the old days, drill sharpening was done by hand.
Today, special devices for sharpening drills have appeared, and their design is very simple.
Why is sharpening needed?
If the drill becomes dull, it is very difficult, and sometimes impossible, for them to drill through the surface. It is also worth noting that for different types drill surfaces must have a certain sharpening angle, for example, for a plastic surface the angle will be 30 degrees, for hardened steel this angle will be 130 degrees.
In cases where a perfectly drilled hole is not required, the sharpening angle can be 90 degrees.
How to properly sharpen a drill
You can sharpen the drill yourself using abrasive discs. During sharpening, the drill must be held by the working surface. You need to hold the tail of the drill with your other hand.
From the side, the drill must be pressed against the abrasive disc. Then it is advisable to turn it with extreme care, as a result the cutting edge will take the required angle and structure.
Sharpening the drill must be done on each side separately. It is also necessary to ensure that the tip of the drill is located exactly in the center when sharpening the cutting part. This must be done correctly, as an error in sharpening can cause the drill to skewer to the side.
Do-it-yourself drill sharpening is not the best good way, since it is capable of carrying with it a number of inaccuracies, for example, the cutting edges may not be correct in relation to the tool axis.
Sharpening device
The device is designed for sharpening blind or through drills made of cast iron and steel. This device is made taking into account the types of sharpening, as well as its size. It is easy to change the sharpening angle on the machine.
There are two types of devices that will help sharpen a drill: a household and an industrial machine. In the first case, the sharpening device takes up little space and fits perfectly into the home, but such a machine can only sharpen small drills.
Industrial machines that are made to sharpen drills with large diameters have great power. The industrial machine has a clamp and a sharpening wheel.
With this device, drill sharpening occurs under the supervision of an operator who can easily control the process. Such devices are designed for long-term operation.
How to make a machine for sharpening drills with your own hands
We will need following materials: abrasive disc, switch, motor with good power, stand, wires, axle and plug. Also for safe use The machine must have a housing, outside of which it is necessary to place an axis with an abrasive wheel for operation.
You first need to decide on the installation location of the machine, since it will be connected to an outlet.
Also, our device should be placed on a table, preferably made of metal, where the engine will need to be placed, and marks should be placed for making holes for the bolts.
An abrasive disc is placed on the motor shaft. To secure it to the shaft, you must first put on the washer, then the disk, and then the washer again. After this, you should install the fastening nut on the pre-prepared thread on the shaft.
An engine from washing machine. The power of its motor will be sufficient for the process of sharpening drills. Wires can also be taken from improvised equipment.
Note!
You need to connect the wires to the starter, which should have three open contacts. The winding must be capable of connecting phase lines using two starters connected in series.
The off button should be connected to NC, and the start button will be connected to NO, and it should also be in parallel connection with two NO contacts of the starter.
When you press the power button, voltage will be applied to the winding and as a result the circuits should close. When the button is released, the voltage supplied to the starter should not be removed. When disconnected, the engine must stop.
The engine itself is a safe device, but to protect its mechanisms from dust it is necessary to make a frame that will protect it from environmental influences.
To make it, you can use a metal box or make a protective screen out of glass. It is also worth installing a casing that covers the end of the disk by a third. It will protect the worker if the abrasive disc cracks.
Photo of sharpening drills with your own hands
Note!
Note!
Drilling metal or wood is a job that you do regularly. A high-quality nozzle does not require sharpening for quite a long time, however, there are some mistakes in which dulling occurs ahead of schedule:
- Using a drill that is not suitable for the material being processed. This does not necessarily mean drilling reinforced concrete with a wood drill, although in this case you will instantly transform cutting tool into a rod with a rounded end. For drilling various types For metal and hard plastics, there are specially made drills. If there is a discrepancy, the cutting edge quickly becomes unusable;
- Incorrect sharpening angle. This value must also correspond to the type of material in which the hole is made;
- Overheat. The most common reason. When working with durable material, we want to finish drilling quickly, and we often forget about such a little thing as cooling the work area. If it is not possible to supply coolant to the tool, it is necessary to take breaks to cool down. cutting edge. You can dip a hot drill into a container of water.
The mechanism of hot blunting is simple: the hot edge “releases”, that is, it loses its hardness. Cutting properties deteriorate, which leads to increased friction. Heating increases more strongly, and the process worsens in arithmetic progression.
As a result, we may lose a good and possibly expensive instrument. If you have it on hand grinder for drills, the problem is solved on the spot; if not, you have to invent your own sharpening methods.
Manual sharpening without tools
A mechanic with extensive experience sharpens drills by hand, using only a sharpener with a tool. But not all home craftsmen can boast of such skills.
In addition, this method can only restore the sharpness of products large diameter. Then it is easier to control the angle. The most popular size (3-5 mm) cannot be sharpened this way. Even a template won't help here.
Craftsmen who regularly carry out drilling work will be interested in the variety of sharpening machines for drills offered in power tool stores.
However, such devices (despite the obvious ease of use) are quite expensive. So the “homemade” people run to the store for another Chinese tip. But experienced home craftsmen still use tools from the times of the USSR, which meet GOST standards in terms of strength and durability.
The secret is simple - many old-school locksmiths have in stock homemade machine for sharpening.
IMPORTANT! For most household projects, you can get by with simple sharpening tools. Especially if the word “machine” scares you.
The simplest devices for straightening the cutting edge of a drill
To understand the process, let's take a look at components tip.
Then, by turning the stock, a plane (more precisely, a cone) of the back is formed.
The sharpening is checked on a template and assessed visually. All planes comply with the standard.
A guide is welded to the bottom (rear) part of the angle stock to support the drill shank. The stop itself is welded from a coupling and an angle.
Fixation is done using a screw. The stop sets the maximum size of the edge to be ground, and thanks to this, both cutting element The drills are ground symmetrically.
The working edge is sharpened against the direction of rotation of the sanding wheel. In this case, the resulting burr is automatically removed by the running surface of the emery. For sharpening, two or three swings of the stock along the radius of the backing cone are enough.
The drill type sharpened along the outer surface of the emery stone; if necessary, use the lateral (radial) plane - the device can be rotated to any angle.
The drill sharpening machine is attached to the workbench using a clamp. You can fix the base permanently, but in this case you will lose the possibility of precise adjustment.
When working with hard workpieces, working surface drills wear out quickly. A dull drill becomes very hot and loses strength. This occurs due to the “releasing” of the metal. The tool must be sharpened periodically. However, this applies not only to drills.
Drills are inexpensive devices. In any case, those models that are used in household. However, it is wasteful to buy a new tip every time it becomes dull.
There are factory-made sharpening devices, but this violates the concept of economical use of home tools.
Wood drills practically do not become dull, except that the tool can be “driven” at high speeds into a resinous workpiece. Pobedite tips cannot be sharpened with stones. All that remains is to sharpen the drill for metal. Many experienced locksmiths carry out this procedure without any equipment.
However, the accuracy of the work leaves much to be desired, and not everyone has an eye home handyman developed so professionally. In any case, minimal mechanization is necessary.
How to make a homemade device for sharpening drills?
First of all, you need to acquire a means of control. No matter how you sharpen the drill, you need a template to check the accuracy of the work.
Conventional drills for working with ferrous metals have an edge angle of 115-120 degrees. If you have to work with different materials– check out the table of angles:
| Processed material | sharpening angle |
| Steel, cast iron, carbide bronze | 115-120 |
| Brass alloys, soft bronze | 125-135 |
| Red copper | 125 |
| Aluminum and soft alloys based on it | 135 |
| Ceramics, granite | 135 |
| Wood of any species | 135 |
| Magnesium and alloys based on it | 85 |
| Silumin | 90-100 |
| Plastic, textolite | 90-100 |
Knowing these values, you can prepare several templates and, in accordance with them, sharpen yourself. In this case, you can use the same drill for different workpieces, you just need to change the angle of the top of the working area.
One of the main parameters of a twist drill is the apex angle, which for durable metals(steel, cast iron, hard bronze, titanium, etc.) is approximately 120 degrees.
Deviation of this angle more or less from the nominal value makes it difficult effective work drill. In the first case, productivity drops and the tool overheats; in the second, the drill may simply break, unable to withstand the excessive load.
To maintain sharpening parameters without special devices, must have highly qualified and the experience of a tool sharpener. Well, to a non-specialist, especially in living conditions, it will be almost impossible to do this.
But, having some tools and simple materials, you can make something that’s not very complicated, but reliable device for sharpening the corner at the tip of a twist drill for hard metal.
What you might need to work on the device
To do this you will need the following tools:- calipers;
- marker;
- metal vice;
- Bulgarian;
- pliers;
- welding machine;
- sharpening machine with an emery wheel.
- regular hex nut;
- castle nut;
- bolt of the same size and thread as the nuts;
- twist drill that requires sharpening.
Manufacturing process
The peculiarity of a hex nut is that any two adjacent faces meet at an angle of 120 degrees. The apex angle of a twist drill is approximately the same size for working on hard metals. This random coincidence can be used to make a tool for sharpening a twist drill.
To do this, using a caliper and a marker on the nut, mark the cutting lines to create a triangular slot, symmetrical with respect to the diagonal connecting two opposite corners of the nut. The drill will be placed longitudinally into it before the sharpening process.
To cut out the intended triangular groove in the nut, it is clamped in a vice and, using a grinder, cuts are made along pre-drawn lines. You can use pliers to remove sawed off pieces of the nut.
Next, take a castle nut and weld it with its base to the first nut on the side of the cut groove. Moreover, it is necessary to maintain their absolute alignment, because when small-diameter drills are sharpened, the bolt, having passed through the castle nut, will begin to screw into the lower nut in order to firmly clamp the drill in its groove.
Now we screw the corresponding bolt into the castle nut, which will securely press the drill placed in the groove for sharpening on the emery. sharpening machine.
All that remains is to sharpen the drill emery wheel, using the edges of the bottom nut as a template.
To do this, we simply grind the protruding part of the drill flush with the edges of the nut, which even a first-year vocational school student can easily cope with.
After sharpening is completed, the bolt is loosened and the drill is removed from homemade device and can be used for its intended purpose.
Additions and improvements
During the welding process of nuts, liquid metal may splash onto the threads of castle and regular nuts. To eliminate this nuisance, it is necessary to screw a bolt into them and thereby protect the thread.Since it will not be possible to cover all the diameters of drills with one device, at least two template clamps will be required: one for small drills, the other for large products. Accordingly, in the first case the nuts will be small in size, and in the second - large.