Of course, you have heard more than once about the benefits of emery in household, even if you are not a fan of making crafts with your own hands. After all, in every home there are knives, scissors and other piercing and cutting instruments that require sharpening from time to time. But the price of emery in most retail outlets you won't be happy! And so why not think about making this incredible thing yourself? useful tool?
Many people use drill bits to make holes in metal using a drill press or drill. After a certain time, the drill begins to get very hot and drills worse, due to the fact that it has become dull. And all this happens quite quickly if you drill with a drill at high speeds. There are cases when a drill breaks off in the middle if it was “bitten” when leaving the metal, and the part was not secured.
Accordingly, working with a blunt instrument is pure torture. Nowadays, few people remember how tool sharpeners used to go from house to house with small portable sharpeners and sharpen all kinds of tools, including knives. Nowadays, of course, you can go to the store and buy completely new tool with factory sharpening, and you can also sharpen the drill at home.
To sharpen drills, you should use a commercial sharpening machine, or you can also sharpen them using homemade sandpaper. A sharpening machine is a necessary and irreplaceable thing in the household. It can be used to sharpen almost any tool and can also be used for sanding wood.
Every tool store sells electric sanders. Quite a large selection of them. You can purchase either a very small sandpaper in order to correct dull cutting tools, or a fairly powerful sharpening machine, with which you can grind off a large layer of metal from any part.
The best purchase would be a double-sided electric sandpaper, with finishing wheels on one side and rough grinding wheels on the other. To prevent injury, these circles must have protective covers in case of destruction or damage to the circle while the engine is running. It is also desirable that the electric sharpener have adjustable working stops for the tools being sharpened and spark-proof shields with protective glass.
Electric sanders with adjustable rotation speed are quite convenient. When removing a large layer you need to use increased speed, and it is better to do the “finishing” of the cutting edge at low speeds. This will, of course, prevent the metal from burning. From time to time, when sharpening a tool, it is necessary to cool it in a bath of water.
In the hands of every man there may be an engine from household appliances, and the question immediately begins to linger in my head, how to make emery with my own hands from scrap materials. For this, all kinds of electric motors are used, on the shaft of which attachments specially turned on a lathe are installed, which are designed to clamp the emery wheel.
For this purpose, they usually use engines from old-made washing machines, such as “Volga”, “Riga”, “Sibir”, “Vyatka”, etc. The engines on such machines are quite powerful and reversible. Switches with a starter are also used from such washing machines.
Despite the fact that it seems quite simple, from a Soviet engine washing machine homemade emery is not at all easy to put together. For example, one of the main questions is how to attach a whetstone to the motor shaft. There is not always a thread there, and the diameter of the hole in the stone may not coincide with the diameter of the shaft.
Therefore, a special turned part is needed that would compensate for this disproportion. To make homemade emery with your own hands, you need to know its future parameters. In most cases, asynchronous electric motors are usually used to make emery at home.
For emery, the maximum speed is considered to be about 3000 rpm. A sharpening stone can simply burst at a very high rotation speed. It is best to use an engine at home with 1000 - 1500 rpm. If a 3000 rpm electric motor is to be used, a fairly strong stone must be present and a quality flange made. Most often, high engine speeds are used not for sharpening, but for polishing products.
In order to make emery with your own hands, it is not necessary to use powerful electric motors for such purposes. Although they say seasoned craftsmen, that for a homemade sharpening machine the acceptable power is 400 W, and for home use An engine with a power of about 100 - 200 W from a Soviet washing machine is enough. Of course, it is low-revving, but this is very good.
You can use three-phase and single-phase electric motors to make emery with your own hands. Both are included in a single-phase network. The device is connected to single-phase network through a capacitor.
To connect the engine and the stone, you need to machine a flange. For such purposes, it is best to contact a turner with a drawing of the emery, the dimensions of the internal diameter of the stone and the diameter of the motor shaft. And the rest is a matter of technology and the availability of available materials.
You will have to grind out the flange itself, which is mounted on the shaft and is also secured with a bolt, and a nut, and a washer with a left-hand thread. You also need to take into account that threads are cut on the nut and flange, depending on the direction of rotation of our electric motor shaft. If the rotation occurs clockwise, then the thread should be left-handed, if suddenly it’s the other way around, the thread should be right-handed. During operation of the table emery machine, the emery nut will spontaneously tighten. If you neglect this factor, the nut will work to unwind, and therefore the stone may fly off. And, of course, this is extremely dangerous.
What should you do if it is not possible to manufacture point bushings of a certain diameter? In this case, pieces of pipes may come in handy suitable diameter, and the gaps between the bushings and the engine shaft can be compensated by winding fabric-type electrical tape between the bushings. In addition, you can put the bushings on top of each other.
In this case, the most important thing when winding electrical tape is to maintain uniformity in order to avoid the formation of large beats during rotation. The sleeve is made from a pipe with a diameter of 32 millimeters, equal to the internal diameter of the emery wheel. An emery wheel is placed directly on it so that it can fit tightly without winding.
This bushing system sits quite tightly on the shaft. But fixation with a bolt and washers is required. At home, you can cut a thread in a shaft using a tap, while holding the electric motor shaft in a vice. In this case, it is necessary to determine the correct hole diameter for the thread.
Before you make emery at home, you need to find out the direction of its work. With homemade emery, you can change the direction of rotation of the rotor. If, for example, the motor is from a washing machine, then it is asynchronous, that is, when switching the corresponding windings, you can change the direction of rotation. Also, in motors from old household appliances there are 3 - 4 outputs. For example, with 4 pins, changing the direction of rotation is not difficult.
For these purposes, we find the starting and operating windings using a tester. The resistance level of the working winding is usually 12 ohms, and the starting winding is close to 30 ohms. The working winding is connected to a 220 W network, and the starting winding is connected securely with one end to one terminal of the coil, and with the other end you need to briefly touch the second terminal of the winding and then immediately discard it (special relays are usually used for this). If you use a capacitor motor, the connection circuit will be different.
This means that your emery will spin in one direction, and if, for example, you swap the leads of the starting winding, then the motor will correspondingly rotate in the opposite direction. You can, in principle, do without a starting coil; in this case, after connecting the working winding to the network, you need to turn the abrasive stone in a certain direction, and then the machine will work.
After you have made your homemade emery, you need to figure out how to properly install it on your workbench. This is done using a bracket, which is also removed from washing machine and is attached to the workbench with bolts. The engine, on the other hand, rests on an angle that supports it in a horizontal position, and also has a cutout that completely follows the shape of the engine housing. To reduce vibration, a edging made from a rubber piece of hose is put on the corner.
To avoid injury from the saw and flying debris from the abrasive wheel when working on a homemade sharpening machine, it is necessary to make a casing. It is best to make it from thicker metal - 2 - 2.5 millimeters. This can be a strip of metal rolled into a half ring.
Under the working body of the emery, you directly need to screw a small piece of galvanized iron sheet, which will protect the workbench from sparks during work. For your own safety, all work must be carried out in special glasses or other protection.
As devices for emery, you can use plexiglass, 5 millimeters thick. This glass is attached to the engine casing using hinges; it can be tilted 180 degrees. Also, for the usefulness of the machine, it is necessary to make a support for the workpiece.
Of course, the benefits of an electric sharpener cannot be doubted! After all, you won’t use a new ax or drill every time. And buying sandpaper for this is a bit expensive. But there is a way out, you just need to spend a little time and collect the emery with your own hands. Follow our instructions carefully, provide the necessary protection for the machine and do not neglect safety requirements during operation.
Greetings, Samodelkins!
Today I want to show you how you can use the materials that are (or at least should be) in almost every workshop to make an excellent device for sharpening knives evenly.
Initially, the master wanted to buy a ready-made device for sharpening knives in China (namely in the Aliexpress online store), but he thought why not try to make such a sharpener himself. Moreover, the prices for this product Chinese friends have quite a lot.
For self-made You will need the following materials and tools:
1. Ordinary board;
2. Sandpaper;
3. Screwdriver;
4. Hammer;
5. Thick electrode 1 pc;
6. Jigsaw;
7. A piece of laminate;
8. Bolts and nuts;
9. Wooden handle;
10. Hex key;
11. Fluoroplastic or textolite (fiberglass).
Regarding the attachment of the sharpening stones themselves. The author took a small piece of the clamp, cut it and made holes. As a result, we got corners like this, two identical.
Knives and scissors should always be in working order in the house, and at the dacha the need for sharp tools is even greater: shovels, hoes, scythes, etc. Sharpening everything by hand is tedious and unproductive. You must have a sharpening machine at your disposal. But this is far from a cheap tool, and therefore it’s worth trying to make a sharpening machine with your own hands.
The design of household sharpeners is subject to the following rules.
To make a sharpening machine, you can use a regular electric drill .
For household use need a sharpening machine universal type. Unlike a special one, this type of sharpener can be used to process most household tools. An electric sharpener is used to solve the following problems.
When choosing components for constructing a sharpening machine, you must consider the following technical indicators devices:
In order to assemble a homemade sharpening machine, you need to purchase an electric motor with a power of about 1 kW (this will be enough), as well as a shaft, bearings and two pulleys.
Helpful advice: you can use a unit from an old washing machine as a motor for the sharpener.
You need to remove the engine from an old washing machine of the “Vyatka”, “Riga”, “Sibir” brands. A starter and switch will also come in handy. There may be a problem with attaching the grindstone: the motor shaft does not have a thread and does not have the same diameter as the hole in the grindstone. The problem can be solved using a custom adapter part. The motor from the “washing machine” is low-power: within 100 – 200 W, but this will be enough.
Rotation speed 2700 rpm. and specified power are optimal parameters for a grinding wheel with a diameter of 150 mm. Increasing the rotation speed will lead to the destruction of the stone.
The solution to this problem is carried out in stages.
Important: the direction of thread cutting depends on the direction of rotation of the electric motor shaft. If the shaft rotates clockwise, a left-hand thread is required, if in the other direction, a right-hand thread is required. Otherwise, the nut will unwind and the stone will not stay on the shaft.
The direction of rotation of the electric motor rotor is not always satisfactory. To change it, in asynchronous motor it is necessary to switch the windings. To do this, do the following.
The final assembly of the sharpening machine consists of the following steps.
Important: it is necessary to maintain a safe distance between the grinding wheel and the workbench plate (minimum 10 mm).
In conclusion, we suggest you watch the video in which the designer will introduce you to another design of a sharpening machine.
The service life of any knife directly depends on the methods of its operation and the procedure for sharpening the blade. Devices for sharpening knives are so diverse that they allow to modern man do not resort to the work of specialists, but do all the work yourself at home. You can use a special tool to sharpen knives. industrial production, as well as any device manufactured with my own hands. It is important to know that simple elements for sharpening knives (for example, a whetstone), which are at hand, can do a bad job and the sharpness of the product will not only not return, but gradually the product will completely become unusable. Moreover, any homemade device for sharpening knives can be based on the use of these simple sharpening devices. Details on how to make your own sharpener can be found below.
A homemade manual machine for sharpening knives, provided that all the requirements for its creation are met, will simplify the sharpening of knives and its performance will be no worse than that of a professional. Proper sharpening includes next rule: each type of cutting product has a certain edge sharpening angle, which must be constant along the entire length of the blade (see table No. 1). A sharpening device that will initially be based on this principle will give the craftsman a sharp knife edge for a long time.
Table No. 1. Sharpening angle in parallel with the type of cutting device
When sharpening the edges should be processed evenly. To fulfill this condition, the following rules must be observed:
The simplest device for sharpening knives is based on the use of an angular frame and a whetstone. The price of such a primitive factory-made device is quite high, as is the price of replaceable whetstones, but making such a device for sharpening knives at home will not be difficult for a craftsman. You will need the following equipment:
First you need to make a pair of wooden corners, placing the bars to each other strictly at an angle of 90º (Fig. 1). Close the resulting wooden corners together parallel to each other as a single whole and drill holes through the diameter of the bolts. Insert bolts into the holes and tighten the corners slightly with nuts.
The point of this invention is that it is possible to sharpen simply by holding the knife vertically in relation to the sharpening surface located at a given angle.
The most important thing is to properly secure the touchstone between wooden corners devices. To do this, using a protractor, you need to set the desired angle of inclination of the touchstone and tighten the bolts tightly to clearly fix the position of the touchstone.
With some modification of the device, you can also fix the position of the knife relative to the sharpening stone. A significant disadvantage of such a machine for manual sharpening it is impossible to smoothly adjust the angle of inclination of the sharpening stone.
Diagram and drawings of a homemade knife sharpener made from mounting angles, based on the Lansky device, are clearly shown below.
To assemble this device you will need:
In both metal jaws, intended for fixing the keystone, you need to drill for a connecting bolt. Fix the touchstone. A thin smooth knitting needle, previously bent at an angle of 90º, must be inserted and secured in the hole of one of the jaws. In the future, using this knitting needle-shaped clamp, a certain angle of inclination of the touchstone will be set. Such a device for sharpening knives is characterized by a wide range of sharpening angles, which will undoubtedly be of interest to most craftsmen.
Knife sharpening machines with locking blades will attract the attention of those people who want to sharpen a knife not only efficiently, but also quickly. The design, which rigidly fixes the knife blade relative to the sharpening stone moving at a set angle, allows you to accurately set the angle of inclination.
To create such a homemade machine with your own hands you will need:
The die intended for fixing the vertical threaded rod must be drilled through with a 6.5 mm drill. The hole should be located at a distance of 15 mm from the edge of the die, approximately in the center.
Next, in the resulting hole you need to cut a thread for an M8 stud. The wooden block prepared in this way must be screwed to the base at a distance of 265 mm from the edge using ordinary self-tapping screws 50 mm long, screwed in with reverse side grounds.
After securing the wooden part of the holding device, you can begin to attach the iron plate. In the center of the 200*65 mm plate, you need to drill an oblong groove, 90 mm long and about 1 cm wide. The groove should be located from the edge of the clamping plate at a distance of 60 mm. Additionally, you need to drill a hole at a distance of 20 mm from the opposite edge and cut a thread in it for an M8 bolt. Then you need to attach the clamping plate to the previously prepared wooden base using this bolt. Using another bolt and a suitable washer, you need to fix the clamping plate in the center of the cut groove. The fixation should be clear, but at the same time neat, so as not to damage the surface of the blade.
The most the hard part Assembling this device consists of preparing a control device that will set the sharpening angle of the knife. For this you will need:
It is necessary to drill a couple of holes on a piece of plywood: a through hole with a diameter of 8 mm along a cross-section of 42×18 mm (the distance from the edge on the 42 mm side should be set at 15 mm) and a through hole with a diameter of 5 mm along the side with a cross-section of 42×25 mm (the distance from edges 10 mm). Square pipe should be cut in half so that you get a “U”-shaped bracket with a width of 40 * 15 mm and ears of 20 mm. You need to drill 8 mm holes in the ears, into which an M8 pin will later be inserted. Connect the resulting bracket with furniture hinge using rivets. Using the second part of the furniture bracket, attach a block of plywood to the resulting structure with an M5 bolt.
Connect the touchstone to a guide rod, which is a steel rod with a cross-section of 8 mm. When connecting the keystone and the guide rod, you should strictly ensure that their center lines coincide. If desired, for ease of use of the sharpener, a handle-holder can be attached to the whetstone on the reverse side. All that remains is to fix the whetstone in the guide mechanism, secure it with a thumb and the homemade device for sharpening knives is ready.
Machines with fixed sharpened surfaces are a simple modification of the device for processing household knives. In such a device there is no possibility of adjusting the sharpening angle; however, several different angles for sharpening can be set in advance different types knives. The work of sharpening blades using such machines is not difficult; you just need to move the blade along the abrasive surfaces in the recess.
The device consists of a pair of planes inclined to each other at a certain angle, one of which is a grindstone.
The procedure for creating an electric sharpening machine is simple: it is enough to equip almost any device for sharpening knives and scissors with an electric drive. Such a sharpening machine allows you to quickly and efficiently sharpen the product and at the same time provides a better concave shelf at the edge of the blade.
The mechanism of an electric sharpener for sharpening knives contains a guide, which is located along the axis of rotation of the sharpening stone, and with the help of which the blade is adjusted at a given angle. The sharpening angle is set and set by the guide, and the clamping force is determined by the master.
Particular attention must be paid to the speed of sharpening, because... The electric drive allows you to sharpen the product at high speed, as a result of which the surface of the knife heats up. Such surface heating leads to tempering of the hardened steel, as a result of which the knife can quickly lose its hardness and its service life will be noticeably reduced. To prevent tempering of the steel, sharpening should be done on a high-speed electric sharpener in short periods of time and with sufficient breaks to allow the knife to cool.
It will not be difficult for a modern craftsman to make sharpening stones with his own hands. For this you will need:
You can use ready-made powder as an abrasive, or you can prepare your own abrasive, for example, from an old block Green colour still of Soviet production. Such a block can be ground into powder and used in the future as an abrasive.
The wooden die needs to be treated on one side with sandpaper and frequent cuts must be made with a saw. Mix epoxy resin with abrasive chips. Having previously placed the block in a cardboard box glued to the size of the block, cover the prepared surface wooden block mixture epoxy resin and abrasive. Once the resin has completely cured, the block is ready for use.
Another option for making your own sharpening stones is to create a sharpening stone from small rectangular glass plates about 5 mm thick. Using double-sided adhesive tape, stick to the surface of the glass plate. sandpaper. The sharpening stone is ready for use.
A simple device for sharpening knives is a tool consisting of a pair wooden slats and pairs of bars with abrasive, with the same geometric dimensions.
Wooden slats should be thoroughly sanded with abrasive sandpaper. Then, after applying auxiliary markings, depending on the sharpening angle of the knife, make cuts to a depth of 15 mm. Insert sanding blocks into the resulting holes so that each groove matches, then secure them with bolts. To give the sharpening device greater stability, the lower part of the surface can be padded with a piece of rubber.
Types of sharpening devices cutting tool are different and each master will be able to choose the one manual machine, which will fully satisfy his needs.
Electric grinders, or, as people say, emery stones, are collected in a great variety from everything that falls to hand; they are often made from motors from washing machines.
I also decided to make myself a homemade machine for drill sharpening, knives, etc. I have a Chinese sharpener, but its quality 😥 well, you understand...
Making such a machine turned out to be one of the easiest things to do :)
Because:
I installed an electrical box on the engine, placed a capacitor in it to start the engine, a toggle switch - a switch and a power supply for the lamp.
I used a toggle switch from a Soviet tube TV - it turns out to be a reliable thing; first I installed a modern, beautiful Chinese toggle switch - when using it, the machine “stuttered” (worked with some jerks), and replacing the toggle switch with another of the same brand did not help until I installed a Soviet toggle switch.
Out of curiosity, I later installed these Chinese toggle switches on another engine, which also began to “stutter”, it’s a shame, I paid 100 rubles for 2 toggle switches. - I just threw money away...
Well, with the capacitor - everything is standard, I won’t describe 101 times how to connect a three-phase motor to 220V - it’s easy to find on Google, or in our article on.
Also check out these articles
For illumination I used an unnecessary LED table lamp from IKEA, bought for home, but was not useful anywhere, the lamp is powered from the mains through an adapter, which I ripped out and hid its board in a box on the motor.
To attach the hand rest, I used one ground at the desired angle furniture corner, then I attached a piece of a 32x32 corner to it, in which I sawed a groove and installed a tool rest on it from a piece of 4 mm steel. The tool rest is fastened with a countersunk screw; thanks to the groove in the corner under the tool rest, the tool rest can be moved closer or further from the grindstone. The corner is also attached to the casing with a screw, which allows you to adjust the angle of the tool rest relative to the whetstone.
I made a corner for fastening from a furniture hanger protective glass, for this I used a piece of plexiglass 6 mm thick.
Whetstone used 200x20 mm gray- I like these ones better for their stiffness, the white ones crumble a lot. I know about marking stones, but I don’t do professional steel processing to spend a long time selecting a stone according to its parameters.
When installing the stone, I placed two cardboard washers, as required, so that when tightening the nuts, the whetstone would not burst.
We read the theory - we know...
The casing of my emery machine is not closed on one side - for safety reasons this is not possible, the casing should cover the stone as much as possible, but I decided for myself that sometimes it is convenient for me to sharpen something on the side of the stone, although this is not recommended. And in general, I usually finish my machines gradually, I think in the future, when I want, I will still make a cover for the casing so that it covers the sharpening stone on all sides.
But my machine also has safety advantages:
The engine is taken depending on your needs, if you are going to sharpen only awls, small knives, etc., then an engine from a washing machine from the USSR will suit you. Such engines usually have 1380 rpm. per minute and 180-250 watts of power. Now there are motors from modern automatic washing machines, but they are more difficult to connect - you need a special board, but you can regulate the speed on them.
For more confident work, it is better to take a 400W engine and 1380-3000 rpm. Such a sharpener will be a good help in the workshop.
But if you want to work with large parts, sharpen crowbars, for example :), then you need to use a motor of about 750 W or more and 3000 rpm.
Photo of self-made emery:
