Do-it-yourself knife sharpener - a master class on how to make it yourself, choosing materials and tools for creating at home

An apartment kitchen, a fishing camp, a hunting lodge - in these places, as in many others, knives are required. Working with any knife only brings joy and satisfaction when the knife is sharp. An incorrectly sharpened knife is no different from a dull one, so below we will talk about how to create a machine for sharpening knives with your own hands without the use of complex technologies and expensive materials.

What to do with dull knives?

If there are no problems with knives with replaceable blades (naturally, if these same blades are present), then a knife with a sharpened blade must be periodically sharpened. Typically, a special knife sharpening device is used for this.

Buying this now is not difficult. But not everyone prefers this solution to the problem. And the point here is not only the considerable cost of such devices. High-quality sharpeners cost a lot of money.

Many craftsmen will get great pleasure from a machine designed for sharpening knives, made by themselves. Although, even using an ordinary “bare” block, of course, you can sharpen knives with your own hands, but in order to sharpen a knife efficiently using only a whetstone, also known as a “block”, you need to have a certain skill and “steady” hands, because you will need to maintain the sharpening angle identical along the entire cutting edge, and this is not the easiest task. A special sharpener for knives is designed to make it easier, be it factory-made or made with your own hands.

But just to speed up sharpening, any sharpener, both factory-made and home-made, will help.

About the safety of a homemade sharpening machine

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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.

Also in terms of safety, it is recommended that the steel thickness for the protective casing be greater than 1 mm - I will also consider this in the future.

But my machine also has safety advantages:

• the protective glass on Chinese machines is much thinner than I used;
• The machine speed is 1380 rpm, although the whetstone is designed for 3000 rpm. per minute This means my stone will have a very small chance of breaking.

What are the differences between abrasive stones?

Sharpening stones come in a variety of shapes, bar sizes, and grain sizes. The optimal size of the bar is considered to be one in which its length exceeds the length of the blade of the knife being sharpened by at least one and a half times. This allows you to work with such a bar much more comfortably than with a bar that does not meet this simple requirement.

As mentioned earlier, sharpening stones can have not only different sizes, but also very different grain sizes. There are five main levels of grain size for such bars:

• Grain size 200-300 Extra coarse. In English called Extra coarse. Such bars are not used for sharpening tool blades and knives in particular;
• Grain size 300-350 Coarse grain. In English called Coarse. With the help of such bars, damaged or very dull blades are sharpened;
• Grain size 400-500 Medium grain. In English called Medium. You can do without such a block in the household;
• Grain size 600-700 Fine grain. Called Fine in English, these whetstones are the most popular for sharpening tool blades in the home workshop.
• Grain size 1000-1200 Very fine. In English called Ultra fine. These bars are used for final processing of blades that need to be brought to a shine. Such bars can be used as a tool for a homemade knife sharpener.

Making a sharpening machine with your own hands step 1

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 calculating a capacitor.

Why do knives get dull?

In order to ensure long and comfortable work with a knife after sharpening, first of all try to answer the question, “Why do knives become dull?” Why is it necessary to sharpen the knife again some time after sharpening, and sometimes to completely sharpen the knife again?

The reason for the loss of sharpness by the cutting edge of any tool is this: when working, the cutting edge of a knife or any other tool is exposed to the smallest abrasive particles of the material being cut.

Such particles are found in any material, be it stone, wood, or food.

Even soft vegetables and fruits contain such particles. There may just be more or less of them, but they will definitely be there. Their size, sharpness and quantity only determine the speed at which the instrument will become dull.

Backlight for sharpening machine step 2

For illumination, I used an unnecessary LED table lamp from IKEA, bought for home, but 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.

Next, I made a protective casing from 1 mm steel.

Sharpening angle, what is it?

So, since it is impossible to stop the process of dulling the cutting edge, then at least try to slow it down, and for this you need to sharpen your tool very well. Earlier in this article you have already come across such a concept as the sharpening angle of the cutting edge. And now more about it.

Blade sharpening angles can vary greatly. From an angle of about 10 degrees for razors and scalpels, to an angle of about 50 degrees for various Machete-type knives.

Possibility of adjusting the position of the knife

An alternative to a machine with a moving sharpening stone is a device where it is possible to adjust the position of the knife relative to the whetstone. Basically, its design is similar to the machine with an adjustable bar, a little easier to manufacture.

A movable block is mounted on the base plane to secure the rod with the bar. Clamps are also installed on it, one is adjustable, the other is persistent. Using an adjustable clamp, you can adjust the sharpening angle.

The only drawback of this model is the appearance of wear on the bar in one specific place. This drawback can be eliminated by installing a long pin to adjust the edge relative to the surface being processed.

Each option described above has its own advantages and disadvantages. When making your choice in favor of one model or another, you need to focus on the level of skills and the magnitude of the needs for operating the machine.

What could cause such a significant difference?

The fact is that the sharpening angle depends on what materials the blade is supposed to cut. The smaller the angle, the softer the materials should be and vice versa.

The fact is that a blade with a small sharpening angle will not only be easier to cut, but will also become dull more easily. That is why there is not and cannot be a single universal sharpening angle.

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After reading this article, you will not only learn how to properly sharpen a knife so that it can serve you for a long time until the next sharpening, but also answer your question about how to make such sharpening easier.

To facilitate the correct sharpening of knives, a lot of different tools have been invented, from the simplest devices to the most exotic ones, at a quick glance at which it is not only unclear how to work with them, but it is also difficult to figure out what it is in general.

How to make a budget knife sharpener

Necessary materials:

• plywood or MDF;
• wooden block;
• round pipe (steel or aluminum);
• nuts;
• threaded rod;
• profile pipe.

The peculiarity of this design is that there is no need to make a base for it - all structural elements can be fixed directly on the work table while sharpening the knife.

The first step is to make a guide sleeve for the handle with the form.

We cut out a round piece of the required size from a piece of plywood or MDF, and then drill a hole in the center. We press a piece of round pipe into the resulting ring.

A round pipe will be inserted into the guide sleeve. You can take a steel one, but in order not to make the structure heavier, it is better to use an aluminum tube.

Next, we need a wheel with a mount from a cabinet or chair.

The wheel itself (in this case it has the shape of a ball) is removed. Instead, we attach a guide sleeve using 2 self-tapping screws.

We weld a nut to the end of the round pipe. If you are using an aluminum tube, it can be rounded and pressed inside. Or you can solder the nut using special solder.

We screw a piece of threaded rod into the welded nut.

We screw the mount with the bushing to the end of a wooden block, which is mounted on the desktop in a vertical position. We insert the handle into the guide.

We cut two identical pieces from a rectangular profile pipe and drill holes in them.

We put the blanks on the threaded rod and secure them with nuts. Between the clamps we install a form for sharpening the knife.

The knife or hatchet itself is attached to the edge of the work table using screws.

You can watch step-by-step instructions on how to make a simple knife sharpener with your own hands below in the author’s video. This idea was shared by the author of the YouTube channel Be Creative.

How to make a Knife Sharpener | Be Creative

If there is no space on the workbench, then you will need to make a base. You can use a piece of plywood or furniture board for this.

Advice from the master: it is better to start sharpening the cutting edge from the base of the knife, smoothly moving towards the tip.

What knives can be sharpened?

Not all blades can be sharpened at home, but only blades made from not very hard materials. So, if the hardness of the material from which the blade is made exceeds 55 units on the Rockwell scale (55HRC), then it will not be possible to sharpen it with any tool available to most people. But most of the knives produced now are made of fairly soft materials and such knives are not at all difficult to sharpen.

True, their service life between sharpenings is not long at all.

But no matter what metal the knife is made of, sooner or later it will still have to be sharpened. The only exceptions to this rule are knives with replaceable blades and ceramic knives that cannot be sharpened at all. Thus, a knife sharpening device must be universal, that is, it must be able to sharpen various blades with different sharpening angles.

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Therefore, when creating a device for sharpening knives, it is necessary to provide for the possibility of sharpening blades with different angles, and this is the most difficult task both at the design stage and during the manufacture of such a device.

Making a homemade machine

It is quite possible to make a knife sharpening machine yourself at home. The main requirement when creating a homemade sharpening machine is to rigidly secure the blade being sharpened and the abrasive element. Thanks to this, the main requirement for the entire procedure is achieved: creating and maintaining a sharpening angle.

Elementary vertical device

The device is designed for quick manual sharpening of knives with your own hands and is a wooden structure assembled in the form of a corner. The exact assembly drawing will not be given here, since the dimensions depend on the size of the grindstone used. You need to prepare:

• 4 bars or planks 5-7 cm wide and 2-3 cm thick. The length of the plank is determined by the length of the stone;
• 4 M4-M6 bolts with a wing nut. The length of the bolts is determined by the formula: (thickness of the board) x 2 + thickness of the whetstone + 1 cm;
• 4 self-tapping screws for wood. The length is selected based on the following calculation: board thickness minus 0.2 cm;
• Protractor or other angle measuring tool;
• A drill with a drill, the size of which is equal to the size of the bolt, or larger by one unit of the size range;
• Wood hacksaw;
• Chisel or chisel (or a powerful knife);
• Pencil or marker.

Making the device involves assembling two corners from existing planks. On one of them, at a distance equal to its width, a cut is made with a hacksaw to the middle. Then, from the end of the board, the sawn-off part is chopped off with a strong knife or chisel. A similar chip is made on the second plank. This is done so that when connecting the boards into a corner, both sides have a common plane. Then the boards, with their chipped parts, are joined into a corner. The second half of the device is assembled in the same way. Next, holes for connecting bolts are drilled in the upper and lower parts of the device. The holes are marked at the ends opposite to the junction, 3-4 pcs. on every board. The holes are marked so that there is at least 3 cm from the edge of the board to the outer bolt, and the distance between it and the other holes allows the edge of the sharpening stone to be securely clamped.

A mark corresponding to each of the future sharpening angles is applied on the inside or outside of one of the boards.

Sharpening work is carried out in the following algorithm: the knife to be sharpened is placed with the blade on the sharpening stone so that it is in a vertical plane. Then you need to move the knife along the sandpaper in a back-and-forth motion, with light pressure. Finer sharpening or grinding of the blade on this machine can be done if the sharpening stone, before installing it in place, is wrapped in sandpaper of the desired grain size.

The advantage of such a device is its simplicity, ease of assembly and low cost. The disadvantage is the lack of rigid fastening of the sharpened blade.

Sharpener from mounting angles

The proposed device is more advanced compared to the previous one. The blade to be sharpened is rigidly fixed in it and the angle of inclination of the emery in relation to the blade is fixed. Another difference is that in this device the moving part is a stone rather than a blade.

The device is attached directly to the knife blade, in its upper part. The device consists of two interconnected metal corners and a movable part resting on one of the shelves.

The following figure is schematically indicated:

1. The basis of the design is 2 corners.
2. A movable rod or knitting needle with a thread.
3. Clamping nuts with washers for securing the emery to the rod.
4. Lever.
5. Holes for adjusting the sharpening angle and supporting the moving part.
6. Set of adjusting washers.
7. Tightening bolts with nuts.
8. Stitched edge of the top corner.
9. A sharpened blade or knife.
10. Whetstone (whetstone).

Manufacturing the device begins with selecting the corners of the base. In the vertical shelf of the upper corner, 3-4 holes are drilled with a size larger than the size of the rod by 3 steps. For example, for a rod with a diameter of 6 mm, 9 mm holes are required. The outer edge of the upper plane of the upper corner is ground down “to the bottom” at a distance of 10-12 cm from the end, so that the emery does not touch it when sharpening. In the horizontal shelves of both corners, two holes are drilled coaxially for the coupling bolts. These holes are drilled according to the principle: the first - at the end of the grinded part of the upper corner, the second - 10-12 cm from the first. The thickness of the set of shims should be equal to the thickness of the blade being processed. The diameter of the clamping washers located on the movable rod should be equal to the thickness of the sharpening stone multiplied by 2. As a handle, you can use a piece of PVC pipe of a suitable diameter or wrap several layers of electrical tape. To prevent the moving part from jumping off the blade, the rod on the outside of the upper shelf must be bent in the shape of the letter “L”, or secured with a locked nut if there is a thread.

What properties should a sharpener have?

So, before you make a device for sharpening knives with your own hands, you need to think about its design. And to do this, you need to answer the question: what properties should a knife sharpener have:

First, any device for sharpening knives must securely fix the knife, preventing it from falling out, but without damaging the blade material.

Secondly, a homemade knife sharpener must ensure that the block is held at a strictly defined angle, which is necessary for sharpening the entire cutting edge at a constant angle.

Third, the most difficult and perhaps the most important, a sharpening machine for knives, both self-made and factory-made, should allow changing the angle of installation of the sharpening stone; this is necessary to ensure sharpening of various tools and will even allow sharpening of stepped knives.

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Knife sharpening basics

Knives have different uses and there are even several of them in the ordinary kitchen. There is one for slicing bread and other soft foods, and one for cutting meat, chopping bones, and other hard objects. And these are just household ones. But there are also those who take them hunting and fishing. If you look closely, you will see that they all have a different sharpening angle (this is if they have not already been sharpened at home). It is the sharpening angle that is the most important characteristic, which is determined by the purpose of a given blade.

A knife sharpening device will make your work much easier

At what angle

The sharpening angle is determined based on the main area of ​​application of a particular blade:

• Straight razors are sharpened at 8-12°. Such a small angle allows you to easily cut hairs after finishing, but when you try to cut something else, the blade will become dull very quickly.
• Fillet knives are sharpened almost as sharply - 10-15°.
• To cut food, it is best to sharpen the blade at 15-20°.

  
  If you look at the blade at multiple magnification we will see something like the following:

• For hunting knives and general purpose knives, you should choose an angle of 20° to 25°. A cutting edge of such sharpness will not only allow you to cut soft foods, but will also cope with bones, wood, etc. without much difficulty. Some manufacturers of hunting knives and knives sharpen their blades within a wider range - 20-40°. A knife with a 40° blade cuts much worse, but it copes better with opening cans or other similar work.
• Heavy knives for special purposes (machetes, for example) are sharpened at 30-50°. It will be problematic to cut bread with them, but they cut trunks, vines and other similar objects perfectly.

These are general recommendations based on many years of experience. There are, however, options: some blades have several zones with different sharpening. This makes them more versatile, but the difficulty of sharpening increases many times over.

From the above it follows that the device for sharpening knives must be able to set the required sharpening angle. And this is the main difficulty in its design and manufacture.

What to sharpen

To sharpen knives, sharpening stones of various grain sizes are used. They are conventionally divided into coarse, medium and fine. Why conditional? Because different countries have their own designation of grain size. The most convenient classification is by the number of grains per unit area. It is expressed in numbers: 300, 600, 1000, etc. Some companies also use English terms. Here is an approximate division:

• 200-250 - very rough (extra coarse). They are not used for sharpening knives.
• 300-350 - rough (coarse). Used when profiling the cutting edge of a damaged or very dull blade. If the cutting edge has no visible flaws and you do not plan to change the sharpening angle, this abrasive should not be used.
• 400-500 - medium. Many manufacturers do not have bars of this grain size, since they are easy to do without.
• 600-700 - fine. The main type of whetstones used for sharpening knives. They are used to sharpen knives that have become dull during normal use.
• 1000-1200 - very fine (ultra or extra fine). They bring the sharpened blade to a mirror shine. Whetstones for sharpening knives are required with medium and fine grain; for finishing (polishing) you can take an even ultra-fine one

In addition to grain size, sharpening stones are also distinguished by their origin: some are of natural origin (slate, corundum, etc.), some are ceramic and diamond. Which ones are better? It’s hard to say - a matter of taste, but natural ones wear off faster and are rarely fine-grained.

Natural ones are soaked in water before use or simply moistened with it. They absorb water and, during sharpening, an abrasive paste is formed from water and separated abrasive particles on the surface, which increases the efficiency of sharpening. For the same purposes, you can use a special little (honing oil) or a mixture of water and soap (whichever you prefer). In general, you should try all these options with each sharpening stone and choose the best one.

The shape of a whetstone for sharpening knives is a block, and it is desirable that its length be much longer than the length of the blade - it is easier to sharpen. Bars with double grain are convenient - coarse on one side, finer on the other. To sharpen knives for ordinary purposes, it is enough to have two bars with medium grain (different) and two fine ones (one can be very fine).

Manual sharpening procedure

A device for sharpening knives only makes it easier to sharpen the edge, so knowledge of manual sharpening techniques is mandatory. Without them, it is impossible to sharpen a knife correctly.

The procedure for sharpening knives is as follows:

• First we take a block of medium or coarse grain - depending on the circumstances, we place it on the table. It’s better if it is secured - you won’t have to worry about not moving it while working.
• We calculate the required sharpening angle - it is equal to half the selected angle. We hold the blade at approximately this angle. Now the main task is to maintain this angle constantly.
• All movements when sharpening a knife are without strong pressure. Smoothly and evenly.
• We begin sharpening with a movement “from ourselves”. In this case, in one pass the blade must “pass” along the stone from beginning to end. There is also an important point here: at the point of contact with the block, the edge must be perpendicular to the direction of movement. There are no problems with the straight part - you drive straight, but as the rounded edge approaches, you have to turn the handle to maintain perpendicularity (see photo).

  
  The process of sharpening a knife on a whetstone

• Upon completion of the movement, the tip should remain on the surface of the block. It should not break off, as the tip may become dull, and its side surface may also be damaged. For this to be possible, the length of the bar must be 1.5-2 times longer than the blade. Then the movement will be smooth and uniform, as it should be.
• After the tip of the knife has stopped, we begin the reverse movement.
• We repeat the movements back and forth until a burr is formed on the back of the blade - a thin edge rolled inward. Feel it with your finger, running it perpendicular to the edge (not along it - you will cut yourself). Ideally, it should be even along the entire length of the blade. If not, work on it some more, and not in areas where there are no burrs, but along the entire length.
• When there is a burr, turn the blade to the other side and repeat the same. The burr will move to the other side, but will become slightly smaller.

  
  Once again in the graph - how to sharpen a knife correctly - the movement of the blade along the block

• You change the block, and with movements “from yourself” you continue to sharpen the blade (there is no more reverse movement). Finer grains leave smaller grooves on the edge and a slightly smaller burr.
• Use the same grindstone to process the second side.
• Change the abrasive to an even finer one. Repeat everything again (the movement is still on your own). And so on until you achieve a “mirror-like” edge, and this is achieved on a very small block. This means that the grooves left by the abrasive are very small and the cutting edge is polished enough to cut well.
• But even after this, a burr remained on the back of the blade. We remove it on the smallest block you have. We perform the already learned movement “from ourselves” once for each side, gradually reducing the pressure. In this way, it is possible to reduce the burr to a minimum, which almost does not interfere with work.

At this point, we can assume that sharpening the knife is complete. Some people are still finishing the edge on the old belt. A piece of belt can be secured to a wooden block (glued, not nailed), rubbed with goyi paste. Then pass several times alternately with one side or the other, but turning the cutting edge back. This way the last grooves left by the abrasive are polished and the belt is not “cut” in the process.

What will we make it from?

The next question to consider is.

The materials from which you will make it.

To create such a device you will need the following materials:

• A sheet of thick plywood (can be replaced with a sheet of chipboard) 16 mm thick;
• Self-tapping screws 50-70 mm long; (it is better to use furniture format);
• A drill corresponding in diameter and length to your self-tapping screws or conformation;
• M8 hairpin of appropriate length (approximately 70 cm);
• Aluminum plate (at least 5 mm thick);
• M8 bolts with nuts (it is advisable to use wing nuts, although you can also use regular nuts, but keep in mind that then, with each sharpening, you will have to use a wrench, and this, you will agree, is not very convenient);
• You will also need a small block of textolite or ebonite to create a movable connection between the stud and the frame, which can be adjusted in height (if necessary, it can be replaced with a block made of hard wood, for example, it could be oak, beech or hornbeam);
• Of course, you will also need abrasive stones of various grain sizes;
• You will also need a powerful neodymium magnet (“you can get” such a magnet from an old computer hard drive that has become unnecessary).

Manual sharpener with adjustable stone

This machine is a more complex design, but it is much more convenient to use. The basis for its creation was a model of a machine called the Lansky sharpener.

Lansky sharpener

The advantage of such models is the reliable fixation of the knife blade.

The device is a support table on which the knife is fixed. At the opposite end of the table, a screw stand with a bar is vertically fixed. A guide rod is inserted into this bar, on which an abrasive stone is mounted. By moving the bar along the screw rod, you can change the angle of metal processing.

The advantages of machines with a similar design include:

• high processing accuracy;
• the possibility of replacing the block with sandpaper glued to plexiglass;
• The wide support base allows you to secure the machine with clamps on any table.

When operating the machine, the only difficulty lies in the long-term adjustment of the position of the sharpening stone. If you plan to process different types of blades, you will have to reconfigure the device each time.

What are we going to do?

The tools you will need are: a drill, a drill of a suitable length and diameter, a screwdriver with bits suitable for your screws or format. Instead of a screwdriver with suitable bits, you can also use a screwdriver (but this will be more difficult).

Any tool for cutting metal (a hacksaw or an angle grinder equipped with a cutting wheel).

Safety precautions when working with a homemade device

When making power tools yourself, you should strictly follow safety precautions. If industrial units are equipped with protective equipment, then in home-made devices you will have to make them yourself. You should be aware that operating a sharpener from a washing machine engine without a protective casing is prohibited. It can be made from sheet metal 2.5 mm thick.

The working wheel experiences strong vibration during sharpening. To prevent the sandpaper from being destroyed during work, when installing the stone, cardboard spacers are placed under the metal washers. You should also make sure that the disc has no cracks.

While working, you should stand to the side of the circle so that if it breaks, the fragments do not fly towards the operator.

How will we do it?

Having asked the question “how to make a knife sharpener?” First of all, let’s find drawings for our future knife sharpener, which we will make with our own hands, and to do this, enter the following query into the search bar: “device for sharpening knives drawings.”

In response to such a request, any search engine will return a large number of suitable search results. Choose the one you like.

Having cut the plywood in any convenient way into parts for our future frame, we drill them at the points of attachment to each other, and then fasten them with self-tapping screws or conformat to each other.

On the frame we fix, using a bolt, an aluminum plate pre-processed according to the drawing (it will serve as a clamp for the knife being sharpened).

Next, we attach a vertical section of the pin to the frame and firmly fix a “cracker” on it. It consists of two parts made of an ebonite block (the Cracker is a very important part, it determines the angle at which the abrasive bar and the blade being sharpened will come into contact).

Now let's create a mount for the abrasive stone: for it we use the remaining section of the pin. Two blocks of ebonite or other similar material and two nuts.

Sharpener with rotary mechanism

If the previous two options for homemade tabletop sharpeners do not suit you for some reason, and you need something more practical and functional, we bring to your attention a sharpening device with a rotating mechanism.

The idea of ​​this homemade product was shared by the author of the YouTube channel “Hands from Shoulders”.

Necessary materials:

1. plastic pipe clips;
2. tablet;
3. fastening - screw with nut;
4. polypropylene pipe;
5. bolt 12 mm;
6. professional pipe;
7. T-shaped aluminum profile;
8. clamps;
9. metal plates.

The first step is to connect the two clips together using a screw and nut. In this case, plastic clips are used for a PP pipe with a diameter of 25 mm and an M4 screw.

To prevent the fasteners from touching the pipe, a small countersink must be made on the inside of each clip - for example, using a countersink or drill of a suitable diameter.

At the next stage, we cut two pieces from a piece of polypropylene pipe with a diameter of 25 mm - insert them into the clip, and then fix them.

Now let's start making the homemade base. We saw off a piece of plywood or a board 120 mm wide (length is at your discretion).

We make markings and drill a hole at an angle of about 70 degrees. Cut a piece of PVC pipe with a diameter of 16 mm and insert it into the hole.

For greater reliability, you can additionally secure the pipe with a self-tapping screw or “plant” it with glue.

Next, cut two rings from a piece of polypropylene pipe. We drill holes in them and screw in the screws. These parts will serve as stops for a guide made from clips and pieces of pipe.

To make a rotating mechanism you will need: a bolt with a diameter of 12 mm, an aluminum brand, a polypropylene pipe with a diameter of 20 mm and a corrugated pipe 20x20 mm.

It is necessary to drill a hole in the center in the profile pipe. We also drill two more holes along the edges, and use rivets to attach the aluminum brand to the corrugated pipe.

For the knife holder, two pairs of metal plates measuring 40x80 mm are used. If the knife blade is short, then one pair is enough. We fasten the plates to the T-shaped profile using a screw and nut.

We insert a nut inside the profile pipe, and then screw in an M12 bolt, onto which we first need to put a piece of PP pipe with a diameter of 20 mm. Fix the bolt with a nut on the other side.

We put two metal clamps on the polypropylene pipe and screw them to the base.

The rod for forms can be made from 16 mm PVC pipe. If possible, it is better to use an aluminum pipe. We put two pieces of polypropylene pipe with a diameter of 25 mm on the rod.

To make the connection more dense, you can use heat shrink.

Forms can be made from ordinary glass or plexiglass with a thickness of 4-5 mm. And as an abrasive material, waterproof sandpaper is used, which is attached to double-sided tape.

For form holders, plastic clips are used for PP pipes with a diameter of 25 mm.

We assemble all the design details together, after which we can begin sharpening the knives.

The step-by-step process of making a tabletop machine for sharpening knives with your own hands is shown in the video below.

Razor sharp tool using plastic pipes!

Thanks to the presence of a rotating mechanism, there is no need to unfasten the knife each time to sharpen the opposite side of the cutting edge.

What did we get?

Having assembled the design according to the drawing, you will receive the simplest device for sharpening knives, however, despite its simplicity, this device will allow you to sharpen knives and any other blades quite efficiently.

In order to understand how to use such a device, just enter “video knife” in any search engine.

Did you manage to sharpen the knife? Hooray! You have successfully made a DIY sharpening machine.

We should not forget that any sharpening machine, even if it is made by hand, requires strict adherence to the rules and safety requirements!!!

Basic materials and tools

The principle of operation of a homemade device

In order to construct a homemade emery, you need an electric motor left over from using old household appliances.

It is the electric motor that puts the product into operation, as a result of which the attachments, pre-sharpened on lathe equipment and installed on the motor shaft, sufficiently clamp the emery wheel.

How to choose an electric motor

Most often, craftsmen choose as a motor an electrical device left over from an old-made washing machine, for example “Volga”, “Sibir” or “Vyatka”. As you know, the equipment made during the Soviet era was of high quality, so the engines were also quite powerful, with high reverse performance. From such a washing machine, you will also need a switch with a manual starter mechanism.

The main difficulty encountered is the precise placement of the whetstone directly on the engine shaft. The shaft does not always have a thread; the size of the hole in the stone may also not correspond to the size of the shaft. A specially machined part that will smooth out the dimensional discrepancy will allow you to cope with this task.

The maximum speed limit used in emery is 3000 revolutions per minute. This nuance cannot be ignored, because a high rotation frequency can cause the sharpening stone to rupture. It is preferable to use a product at home with an engine speed of 1000 to 1500 rpm.

Photo of a DIY knife sharpener

We make emery from a washing machine engine with our own hands at the dacha: drawings, videos, photos

Often a situation arises when it is necessary to sharpen a tool or sharpen knives.
To perform these works, a sharpening machine is best suited - it is also called a sharpener or an emery machine. This is the simplest power tool, which consists of an electric motor and an abrasive wheel. There are many options sold in the retail chain, which differ from each other in price and manufacturer, but are designed to perform one function - sharpening a cutting tool.

Do not rush to purchase a factory-made electric sharpener: any home craftsman can make it with his own hands if he has the necessary spare parts.

Material preparation and step-by-step assembly

Outwardly, it seems that making homemade emery with your own hands is easy, but in fact it is a very difficult job. To assemble the mini-structure you will need:

• Electric motor from an old automatic car. The most powerful motor that is suitable for conversion into a machine can be borrowed from old type machines “Sibir” or “Vyatka”.
• Turn off the launcher.
• Sharpener.
• Wires and plug with cable.
• Flange.

The speed of the electric motor from the washing machine coincides with the speed of the factory emery shaft. Therefore, motors with such characteristics are chosen for the manufacture of tools.

The most suitable rotation speed is 1000-3000 rpm. When selecting a sharpening stone, you need to take this rotation speed into account. For example, a weak disk will disintegrate during operation if the rotation speed is 3 thousand revolutions per minute.

To prevent this from happening, choose a durable disc with a dense structure.

Step-by-step assembly of the device. First, determine what size the tool will be. Its dimensions are calculated depending on the size of the existing engine. Then a diagram and drawings of parts are prepared.

The difficulty in assembling an electric sharpener lies in the fact that due to the lack of threads on the motor shaft, it is impossible to attach a whetstone to it. Sometimes the diameter of the shaft does not match the diameter of the stone hole.

To connect the two parts, a special flange is made.

How to make sandpaper from a washing machine motor?

The step-by-step process for making emery from a washing machine motor is presented below.

How to make emery with your own hands from a washing machine

Emery is a tool that every home craftsman needs. It is used for sharpening cutting tools: knives, scissors and other devices. The price of such sharpening tools is very high, so experts are in no hurry to buy them. Since you can make emery with your own hands at home using available materials, craftsmen choose this option.

Flange manufacturing

The flange with the shaft is fixed with a washer and during its manufacture it is necessary to take into account that the threads on the parts are made depending on the direction in which the shaft rotates. To make a flange for emery, turn to a turner with a drawing. Making the nozzle:

• Left-handed threads are made if the shaft rotates clockwise, and right-handed threads are made counterclockwise. The nut will unwind and the sharpening stone will fly off the tool if you do not take this moment into account.
• To produce bushings, special equipment of a certain diameter is used. If there is no such equipment, then instead of bushings you can use simple pieces of pipes with a diameter of 32 millimeters. The residual space between the shaft and the motor bushings is covered with electrical tape. Only electrical tape that is made on a fabric basis is suitable for this. Its winding is carried out evenly, putting the bushings on one after another.
• Thanks to this bushing system, the emery wheel is put on the bushing and securely fastened to it.

A tap will help you make carvings at home. The motor shaft is clamped in a vice, and then work begins. A homemade device allows you to adjust the direction of rotation of the rotor. To do this, the tester determines the starting and operating windings.

The starting winding has a resistance level of about 30 Ohms, and the working winding has a resistance level of 12 Ohms. The working phase is connected to the network, and one end of the starting winding is connected to the coil. Then, with the other end, they touch the second terminal of the winding and sharply fold it back.

If you swap the leads of the starting winding, you can change the direction of movement.

You can start the engine in another way. The working winding is connected to the network, and the grindstone is turned by hand. The tool will work.

Making a support and auxiliary table

The tool requires a support frame. To make it you will need a large pipe and an angle grinder. Manufacturing process:

• Following the drawing, a groove is cut out on the pipe for installing the capacitor. To do this, use an angle grinder. The groove is made on the rectangular section of the pipe from the wide edge.
• To fix the electric motor, small holes are cut out in the corners of the part.
• Then the prepared corners and pipe blanks are welded using a welding machine. This creates a frame.
• The required number of holes are drilled in the frame to install the engine. An electric drill is used for this.
• In order for the table to move to the desired position, two grooves are cut on the surface of one metal plate. The grooves are drilled with an electric drill. Their shape should be longitudinal. In this case, there is no need to make grooves in the second plate, which will be on top.
• A square pipe and 2 metal plates are welded using a welding machine. It turns out to be a table.
• The table and frame are connected by bolting.
• All irregularities and rough places on the structure are cleaned. A metal brush is attached to the grinder and grinding is carried out.
• All metal elements of the structure are coated with paint.

For stability, rubber shock absorbers are installed on the bottom side of the frame. They are fixed with self-tapping screws. The switch is attached to the structure according to the electrical diagram.

Installation and protection of the tool

Making your own emery from a washing machine also includes installing it on the bed. A construction workbench, table or wall is used as a support .

• One side of the motor is fixed with bolts on the workbench, the other is supported on an angle. This angle allows you to keep it horizontal.
• A piece is cut from the rubber hose and the edging for the corner is prepared. This will reduce the vibration level.
• A protective casing is made from a metal sheet 2.5 millimeters thick. It will create protection against pieces that will fly off the abrasive wheel during operation. The metal sheet is rolled up in a semicircle.
• Also, during operation, a lot of sparks fly off from the sanding wheel. To protect the workbench from them, a galvanized sheet is secured under the work area.

DIY mini emery – Metals, equipment, instructions

Making emery with your own hands is not at all difficult, especially considering that the components for it are available and inexpensive. Such a device will become indispensable in the household, as it allows you to quickly and efficiently sharpen tools, kitchen knives, and grind surfaces made of various materials.

The cost of finished emery is quite high, especially for professional equipment. In most cases, parts of a homemade device can be obtained for free or for a purely symbolic price.

Creating such a device from scratch will allow you not only to save money, but also to prove yourself as a true master!

Emery can be used for roughing metal, as well as grinding and sharpening tools.

This question is asked by home craftsmen who are not yet completely sure of the advisability of creating emery.

Depending on the rotation speed and grain size of the abrasive, sandpaper can be used to perform both rough processing of metals and their grinding and finishing.

If there is a stop with adjustable angle of installation, it is easy to accurately sharpen cutters, chisels and drills. You can sharpen an ordinary kitchen knife on this machine in just a few seconds, without much effort.

If your hobby is working with metal, grinding it or forging knives, then using sandpaper and a set of circles of different grain sizes, you can polish the surface of the material to a mirror shine.

Rest assured, having emery in your home will greatly expand your capabilities.

Homemade emery device.

The main working tool of an emery machine is a whetstone, but without a powerful electric motor you can’t get much use out of it. An engine of optimal size and power can be obtained from an old Soviet-made washing machine; fortunately, they can easily be found at the nearest market or in newspaper advertisements under the “I’ll give it away for free” section.

Most washing machines of this type, despite their rather advanced age, have a fully working engine. Its power is about 100-200 W depending on the model. This is quite enough for home emery.

The rotor rotation speed should be no more than 1500, and preferably 1000 revolutions per minute, otherwise the risk of destruction of the grindstone during operation increases, which leads to tragic consequences.

Motors of old-style washing machines are represented mainly by asynchronous models. This means that a simple modification of the device will allow you to change the direction of rotation of the rotor. To do this, swap the connection points of the starting or operating winding.

A standard washing machine motor has 4 outputs: two of them are for connecting to the network, two more are for connecting the starter. They can be distinguished from each other by their resistance. Arm yourself with a regular tester and take resistance measurements.

For the working winding, which is connected to the network, it will be 12 Ohms, while for the starting winding this parameter is 30 Ohms. By swapping the connection points of one of the windings, we will result in the rotor rotating in the opposite direction.

How to assemble emery

Diagram of sandpaper from a washing machine motor.

Homemade emery may have a different appearance from the standard one, but the main components are always the same. These include:

• Electrical engine;
• sharpening stone with lock;
• bed;
• protective casing;
• handyman

Assembling all the parts together begins with choosing the material for the base - the bed. It can be made of sheet metal, wood or durable thick plastic.

Preference should be given to metal, as it has high reliability, fire safety and, due to its weight, ensures the stability of the device on any surface. If the device is mounted with bolts, rubber gaskets can be used at the fastening points.

They reduce the vibration that occurs when sanding. Also, the collapsible design allows you to transport the tool to another place of work at any time.

If you choose not a metal base, but a plastic or wooden base, its surface in the working area should be covered with a layer of galvanized iron 0.5-1 mm thick. This will protect the workplace from fire due to hot sparks hitting a flammable surface.

Figure 1. Shaft adapter diagram.

The electric motor has 4 long mounting pins in its housing, the presence of which greatly facilitates the installation of the motor on the frame.

To do this, two iron corners are welded or bolted to the metal surface, placing them parallel. Two holes are made in them, to which the pins will be attached.

The most difficult stage of assembling a homemade device is finding or making a clamp for the grinding wheel. Due to the fact that the rotor shaft is smaller than the diameter of the hole in the grindstone, a special adapter may be needed (Fig. 1). It allows you to securely fix the stone, preventing it from slipping.

On the reverse side, the sharpening stone is attached to the adapter with a nut, under which a cardboard spacer is installed. The thread of the nut is selected right or left, depending on the direction of movement of the grinding wheel: when moving clockwise, the nut is installed with a left-hand thread, otherwise - with a right-hand thread.

The cardboard spacer is used to prevent excessive clamping force from breaking the abrasive stone.

The most important indicator that a homemade emery should have is safety.

Figure 2. For sharpening corners, it is better to make an adjustable tool rest.

Therefore, such a device must be equipped with a protective casing, which can save not only from small metal particles and sparks, but also minimize the risk of injury in the event of an unexpected split of the sharpening stone.

For ease of use, the casing can be made of transparent impact-resistant plastic. In addition to plastic, you can use sheet iron with a thickness of 2-2.5 mm. Do not forget about the constant use of personal protective equipment for eyes and hands.

A small metal plate called a tool rest allows you to correctly distribute the load on the material. It is designed to rest tools or materials on it during processing. The tool rest can be made adjustable (Fig. 2), so the sharpener can be optimally used for sharpening cutters and other tools for which the angle of the working surface is important.

Safety when working with sharpening tools

Although the described sharpener has low power and is intended for home use, in terms of safety it requires no less care than professional equipment. By adhering to the following rules, you will protect yourself and others from the risk of injury while working:

1. Even for short and simple work, use safety glasses. They will reliably protect your eyes from hot scale and abrasive fragments.
2. Before starting work, check the stone for tight fit on the shaft, absence of cracks and chips. If necessary, replace the stone.
3. Do not touch work surfaces or moving parts with your hands.
4. The device you will be working with is an electrical device and therefore there is a constant risk of electric shock. Therefore, check the integrity of the wire braid; if any malfunctions are detected, you should immediately stop working.
5. Be sure to use a protective cover when working. Yes, it reduces visibility and is not so convenient to work with, but the level of safety with its use increases significantly.

Conclusion on the topic

Self-assembling emery from scrap materials is a fairly simple task that will allow you to get a universal tool for grinding, cutting and sharpening metal materials.

You can now make any knife, chisel or drill sharp in just a couple of seconds, without much effort.

When working with emery, it is very important to follow all safety rules.

Never work without protection for your eyes and hands, even if you think that you have already mastered all the intricacies of this skill.

DIY emery

Many business people wouldn't mind having a functional sharpening machine on hand. Equipment of this type from a good manufacturer is not cheap. It is not at all necessary to spend money on buying a new machine, since it is quite possible to make emery with your own hands, spending a minimum of money and effort.

Among the many power tools needed in the household, emery takes pride of place in demand. It will be useful in the garage for sharpening knives, in the country; will be indispensable for any craftsman.

Guided by the photo and video materials in the article, possessing the necessary set of materials and tools, and with minimal skills, you can easily make homemade emery. The design of the future machine will include: an emery stone (sharpener), a support frame, an auxiliary table, and electrical equipment.