Making a simple knife sharpener with your own hands. Sharper: we study the most effective devices for sharpening knives Knife sharpener drawings

Sharpening knives is a process that even delicate female hands can handle. Indeed, in our time there are many devices that facilitate this task. Ceramic knives, for example, do not require sharpening, which is very convenient, and steel knives require periodic sharpening, since the material is dull. To sharpen the knives, you can use coated abrasive bars or a knife sharpener.

Grinding bar.
Special cut files.
Sharpening accessories.
Knife sharpening machines.

Note.

Sharpening knives the old fashioned way, of course, is a good and effective way, but a finely tuned machine for household use gives a better result with the desired angle of formation of the blade edge.

Knife sharpening rules

Experts recommend following a number of rules in order to get high-quality sharpening of knives at home, which in turn will reduce the number of sharpening of the blade.

If you are a proponent of using an abrasive bar, start with the sharpest part of the blade, and end with the duller one, namely the one that is little involved in the process of cutting food. Often, the process starts in the middle, moving towards the edge of the blade with a slight twist. The shape of the knife and its thickness affects the angle of the blade. The sharpening machine for kitchen knives performs turning at an angle of 25 °, the blade is tilted over the bar by 12 - 13 °.

The type of sharpening machine for planer knives and the material from which it is made also affect the quality of the work.

On various Internet resources, you can find special videos that clearly show the process of sharpening a knife blade.

Note.

Knives are manufactured mainly from alloy and carbon steel. Hardened steel needs to be sharpened with a bar with an abrasive, stainless steel - with a triangular file. This is due to the fact that relatively soft metals, during the sharpening process, forget the surface of the bar with the abrasive. The forged blade is quite flexible, so it is advisable to fix it and sharpen it with a bar in casual movements. Frequent use of abrasive stones contributes to the formation of a greasy film on the surface, which must be rubbed off.

Previously, table sharpening machines for knives were made from wedge-shaped bars and oak. The bars were placed on both sides of the wooden blade, so that the cutting edge was free. The structure was pulled with a rope and, using a grindstone, the blades were sharpened to the utmost sharpness, while obtaining an excellent sharpening angle.

Sharpening knives used in planers is done as follows: on glass of large thickness, impose an emery cloth with a fine fraction, the beveled part of the cutting edge on the abrasive and sharpen in a circular motion.

Sharpening knives at home

For this purpose, you will need to take a block of hardwood, the surface of which is formed by sharpening at a certain angle necessary to form the edge of the blade. This makes it possible to keep the corner of the cut edge. For the convenience of sharpening the blade, fix the blade in the plane of the bar using self-tapping screws.

Sharpening machine for jointer knives, make a tool with your own hands, this will make it possible to make the process easier, and the quality of work is much higher. The main thing is to follow the rules and nuances in the work, and there will be no problems.

The do-it-yourself knife sharpening machine is designed to facilitate working with metal products. Household tools can be sharpened with their own hands with the help of improvised tools, and in production you cannot do without a machine. There are more volumes and more serious tools.

Professional knife sharpeners

The sharpest tool is considered to be a rock cutter or a carving knife.

This is used by butchers for cutting animal carcasses, and cutting off the skins. With such intense work, the tool blade dulls extremely quickly. If the volume of work is not too large, sharpening can be done on a conventional machine, which is equipped with control over the angle of the blade edge. Knife sharpening machines in the meat processing industry are mainly used by KNECHT USK 160. Such machines are universal, so absolutely any knives can be sharpened on them.

At enterprises engaged in woodworking and in carpentry shops, equipment is installed that can cope with large volumes of work. It uses a tool that has long-blade jointers and planers. Sharpening of metal takes place on equipment with a mechanical drive, which feeds the tool for sharpening.

When trying to sharpen a tool yourself with a sharpening bowl

… Without the use of fixation and guides, zones with different angles will be formed on the blade. When processing wood with a poorly sharpened tool, you will get an uneven cut and a wavy surface. The sharpening machine for flat knives has a simple vertical design, the discs are sharpened on machines with a separator and a rotating table.

Universal knife sharpener

This type of equipment is best suited for enterprises that perform large volumes of work per day. No one will tinker with metal by hand, since it is hard work. The VZ-319 benchtop machine is equipped with a rigid bed and a precisely fitted mechanical drive. Therefore, it copes with sharpening any type of tool - planers, cutters, knives, etc.

For domestic use, the Tormek T7 model is suitable. The equipment of this unit is large, there are many attachments and additional elements for sharpening kitchen knives, scissors and other tools.

Making a knife sharpener with your own hands

It is quite simple to make a knife sharpener for household use, for this you need a piece, or, a wooden rail, sandpaper, bolts with thumbs. The first step is to make a knife holder, for this purpose cut off a piece of material. In order to avoid clinging of the bar to the holder, you need to clean the edge at a certain angle using emery. On a vertical stand, mark up and cut off the top, this will serve as the basis for. The angle is set to half that required for sharpening the blade.

For household knives, the angle is 10 - 15 °. To facilitate the construction of a knife sharpening machine, make a drawing, so it will be much easier for you. Take into account the fact that the height is influenced by the transverse base. Finally, all elements need to be trimmed and sanded. Then, you need to make holes for the bolts in the plate, which will fix the blade. When marking, determine the distance of the holes from the edge of the base. This will allow you to sharpen blades of different thicknesses.

In the next step, the plate needs to be secured using bolts. The uprights are fixed with screws. It is important to remember that the pressure on the bottom is small, so thermal glue can be used to fix the elements. The horizontal bar is attached in the same way.

To make a bar, you need to cut a rail of a certain length. At one edge, sandpaper is attached with a sufficient fraction of abrasive particles. In order to achieve a better result in work, you can make more bars with different abrasives. A good grit range is P600 - P2000.

Note.

To protect your hands from injury when sharpening the tool, screw the handle onto the top of the rail. Thus, you get a machine for home use with good functional qualities.

In the process of sharpening knives, the device receives support on the table, which in turn makes it easier to work with it.

Interest in making do-it-yourself knife sharpeners arises for a reason. The consumer qualities of hand cutting tools are increasing due to the use of modern materials and technologies for the manufacture of the blade and precise factory sharpening. At the same time, the price of the product is also growing, but it is becoming easier to spoil a rather expensive thing with a primitive sharpening. Therefore, various household tools for sharpening knives are needed not only for convenience. To understand why a knife sharpener is still needed and how to make it correctly, you will have to start with the ideology and evolution of the knife.

Why do you need a sharpener

A living relic of our days is a Finnish hunting knife. Not a bandit finca, sometimes of a bizarre shape, but a Finnish-type hunting knife, on the left in fig. Traditional hunting knives (center and left) are similar in shape, but the difference between them is very large.

A Finnish knife blade is forged from blast iron, which can be smelted right in your yard from swamp ore in a blast furnace, without resorting to blast-furnace processes, puddling, and other methods of converting cast iron into iron and steel. The viscosity of the blast iron is excellent, it is very difficult to break a blade from it. But the hardness is also low, somewhere HRS55, the knife gets dull pretty quickly. Finnish hunters did not care about this: a blade of such hardness can be directed (sharpened) with a beating on many natural stones, and there were always enough ironed moraine boulders in Fennoscandia.

They sharpen a knife with a chop in about the same way as they beat off a scythe, only the touchstone is motionless, and the blade is moved. First, it is pulled along the donkey with its butt away from itself, then it is turned over and pulled with its butt towards itself. The position of the cutting edge (RC) on the donkey is always dragging; fast movements: shirk-shirk! On each movement, you need to keep the contact patch of the blade with the touchstone (see below), but the requirements for maintaining the angle of inclination are not so strict. Learning to sharpen a knife with a chop is not very difficult, and with some skill, you can direct a smoothly running profile onto the blade, see below. However, the Finnish knife is in general a dead end for the evolution of cutting tools, which survived in special natural conditions.

A good knife was never cheap, and in an extreme situation, the durability of the blade, combined with the toughness of the blade, became vital circumstances. Therefore, even in antiquity, the blades of knives learned to harden from the surface and cement: the core remained viscous, not brittle, and a hard hot crust formed on it outside, see trace. rice.:

It is still possible to direct a knife with a cemented blade with a chop, but a skill is needed that is not given to everyone. And the abrasive is already needed from a special kind of stone - Grünstein lithographic slate. There is little of it in nature; Grunstein is still considered a strategic raw material. There is no artificial grunstein and is not expected. It is as easy as shelling pears to spoil a cemented knife with an inept beating - a little somewhere the cementation crust is pulled off to raw metal (this is not visible to the eye), the knife will only have to be thrown away, the blade will immediately become blunt and crumble.

Note: if you have an old scythe donkey of a slightly greenish color lying around somewhere, do not throw it away, it is a valuable rarity.

Household workers do not need such stamina and toughness as hunting and marching ones, and they should cost a lot less. As a result, special steels and powder metallurgy are widely used in the production of household goods. The blade of the "eternal" kitchen knife is structured like a rodent's chisel: longitudinal layers, the hardness of which falls from the core outward. In any case, the knife has to be sharpened less often, but the beating is unambiguously excluded - the blade from it immediately crumbles.

How do you sharpen a knife?

For these reasons, a push-pull sharpening technology has long been invented:

The blade is pushed on the touchstone away from you with a twist, holding the butt towards you, the position of the RK is oncoming (scraping);
Then, without removing the blade from the touchstone, pull it with the butt towards you with a turn in the opposite direction, the position of the RK is dragging;
The blade is turned over and paragraphs are repeated. 1 and 2;
Pp. 1-3 are repeated, in each cycle, reducing the pressure, until the burr formed on the RC comes to naught (does not merge).

Note: when they say or write "the burr will go away", etc., this is incorrect. The metalworkers have the slang word "zausyavka"; for electricians - "off". But in Russian, the burr and the switch are masculine.

Push-pull sharpening protects the blade, but requires high skill from the operator, because a number of conditions must be observed continuously and precisely during the sharpening process, see also fig. below:

Maintain the angle of inclination of the blade to the touchstone, smoothly changing it in accordance with the curvature of the RK.
Make sure that the tangent to the generatrix of the blade and the transverse axis of the contact spot between the PK and the donkey coincide.
Also make sure that the axis of the contact patch is always perpendicular to the longitudinal axis of the stone.
Smoothly change the pressure on the blade as the area of the contact patch changes.

It is very difficult to comply with all these conditions at the same time, completely symmetrically on the forward and reverse movement of the blade along the touchstone, and a modern knife, as mentioned above, can be damaged by improper sharpening. Any household device for sharpening knives is just intended to save the grinder from continuous control of at least part of the specified conditions.

Note: for successful push-pull sharpening, the length of the donkey (see below) must be at least 2 lengths of the knife blade from the handle to the tip.

Sharpening profiles

The blade profile of a knife is linked to the material properties and structure of the blade, as well as to the properties of the materials for which the tool is designed. Sharpening with a simple blunt wedge (pos. 1 in the figure) gives a stable but coarse blade: the cutting resistance is high, and the knife tears rather viscous materials. A sharp wedge (pos. 2) quickly dulls or crumbles; on viscous and / or fibrous materials, the cutting resistance may be greater than with a blunt wedge due to friction of the cut off blade.

Ideal in all respects is the ogival (smoothly running off) profile, pos. 3. Experts still argue which generator is better - involute, hyperbole or exponential. But one thing is indisputable - it is difficult and expensive to make an ogival blade in production conditions, and it is impossible to direct it yourself. Therefore, ogival-sharpened knives are used only in special equipment, for example. microtomes - biological devices for obtaining the finest tissue sections.

For disposable blades, e.g. safety razor blades, faceted sharpening is used, pos. 4, i.e. The ogive generator, as mathematicians say, is approximated by line segments. The number of sharpening edges is indicated in the certificate or on the manufacturer's website. For thick coarse bristles, 3-4-sided is better; for delicate hair not on the face - 8-sided. 6-sided is considered universal.

Angle α

The sharpening angle is always given in half the value of α, because many tools, such as bayonet knives, are sharpened to one side. For knives for various purposes, the angle α is maintained in the next. limits:

10-15 degrees - medical scalpels, straight razors, art carving knives.
15-20 degrees - confectionery (for cakes) and vegetable knives.
20-25 degrees - bread and sirloin knives.
25-30 degrees - hunting, hiking, survival knives.
30-35 degrees - general purpose household knives.
35-40 degrees - carpentry tools, shoe knives, axes.

One and a half

Sharpening of knives, except for special ones, is done almost exclusively with a one-and-a-half profile, on the left in Fig. One-and-a-half sharpening is so named because the flat edge of the blade (escapement) is formed during the manufacturing of the blade and cannot be sharpened. In fact, guiding a one-and-a-half-sharpened knife is no more difficult than sharpening with a simple wedge. One and a half sharpening is optimal for a knife that works with a variety of materials, and making a sharpener for one and a half sharpened knives is much easier than for sharpening a faceted one.

In the center and on the right in Fig. shows the stages of sharpening the blade and the numbers of abrasives used on them. The abrasive number corresponds to the number of its grains per 1 sq. mm surface. The fine-tuning stage has some features:

Hunting and camping knives are not supplied. This makes it easier to cut hard (eg bones) with a broach (with filing). In addition, if you accidentally cut yourself, then a slightly lacerated wound stops bleeding faster, heals more easily and there is less danger of infection entering it.
Blades of dangerous razors, knives for shoemakers and for artistic carving after an abrasive are brought to mirror smoothness on a leather donkey with GOI paste.
Guiding and finishing the blades of kitchen knives can be done in one operation with abrasive No. 800-1100.

Touchstone

A home-made knife sharpener will be much more convenient and more accurate if you do not buy a touchstone for it, but make a piece of a square pipe 200-300 mm long (on the left in the figure below) or a wooden block from a piece.

The edges of the base are pasted over with an emery cloth acc. numbers. Glue is a stationery glue stick. The advantages of a skin based donkey are obvious:

Much cheaper than an emery bar.
Can be made in 4 abrasive numbers, whereas emery stones are maximum 2-sided.
Wear (development) of the abrasive is possible no more than the thickness of the abrasive layer of the skin; waviness of the RK due to the rotation of the whetstone on the sharpener rod (see below) is also no more than this value.
As a result, the error of the sharpening angle from the development and rotation of the whetstone does not exceed fractions of a degree.
A touchstone from a pipe can be put on a threaded rod (center in the figure), which makes it quicker and easier to change the abrasive.
A touchstone from a pipe or a wooden bar is held in any clamps under an emery bar no worse than the last one, on the right in Fig.

Knife sharpeners

The simplest manual knife sharpener is a corner frame in which a whetstone is clamped, pos. 1 per next. rice. The same type of "firm" is on sale, and this is marketing, so marketing: they want up to $ 50 or more for a plastic board with inclined nests for donkeys. Whetstones - non-standard sizes; ordinary ones do not fit into holes. Worked out - you need to buy original ones. You understand the price. And all the convenience - when sharpening the blade, it is still easier to keep the blade strictly vertical than to maintain the angle of its inclination.

The use of the simplest knife sharpener can be further simplified to a complete absence of the need for skills, if it is supplemented with a sliding shoe with a magnetic knife holder, pos. 2. The order of sharpening in this case is the following:

The knife is held with the right hand by the handle, turning in the direction of travel according to the curvature of the blade;
With the fingers of the left hand, except for the thumb, they press the shoe to the donkey;
The thumb of the left hand is pressed on the butt of the blade, pressing the RK to the abrasive.

In this case, the function of maintaining the angle of inclination is removed from the operator, and the rest are distributed over 2 hands. In this case, the skill of sharpening with your own hands is developed immediately, but a holder is needed that firmly holds the knife and at the same time allows it to slide on its surface. This can be done from the magnets of the drive of the carriage of the read-write heads from an unusable HDD (hard drive). The "screw" carriage drive magnets are niobium, thin, flat, even and very strong (shown by red arrows in pos. 3). They are glued with DIFFERENT poles on a steel strip, the force of attraction of the blade will then double. And to ensure sliding, the holder is covered with a fluoroplastic film 0.05-0.07 mm thick. PET from bottles will also work, but it is thicker and the attraction will be weaker. Polyethylene is not good, it will wipe right away.

Note: remember this holder, we will still need it.

LM

It does not require any special skills and the use of a manual knife sharpener of the Lansky-Metabo type, pos. 1 in fig. A diagram of its device is given in pos. 2, and the procedure for use is in pos. 3. The disadvantage of the Lansky-Metabo sharpener is the instability of the sharpening angle along the length of the blade: a rod with a donkey is driven along it. In this case, the offset of the touch point is continuously changing, because it describes an arc of a circle, and a blade of a different configuration. Corresponding "Floats" and the angle. Therefore, the Lansky-Metabo sharpener is used primarily for sharpening camping and hunting knives with a relatively short blade.

However, this disadvantage can be turned into dignity if the blade is clamped in the terminals with the root part A (at the handle) and with the tip slightly turned away from you, pos. 4. Then, at the root of the blade, the sharpening angle will be the greatest, which is optimal for processing hard materials or using the knife as a cleaver. So, after all, they work for them in such cases, so that the outer arm of the arm-blade lever is shorter.

Towards the middle of blade B, the sharpening angle will smoothly decrease and reach a minimum at the bend of its generatrix B1, which is convenient for fine work. Then, the angle will increase again towards tip B, which will make the tip more resistant when drilling, slotting / impacting and punching (piercing).

Note: Another disadvantage of the Lansky-Metabo sharpener is the difficulty of execution in the tabletop version. But this drawback, as they say, is fake, see pos. five.

Part drawings of the original Lansky-Metabo sharpener are shown in fig. The numbers at the windows for the bar (guide) correspond to the FULL sharpening angles.

On the trail. rice. an assembly drawing of the clamp is given, and then - drawings and dimensions of Lansky-Metabo terminals made of a 90x90x6 mm angle. The author of the development is hiding under the pseudonym Serjant. This is, of course, a matter of his modesty. But, by the way, in production, technological innovations that allow the use of standard profiles for the manufacture of shaped parts are sometimes appreciated more expensive than serious inventions.

Note: on the trail. rice. an assembly drawing of the Serjant sharpener is given. About the inconvenience of fastening in a vice - see above.

Knife sharpening machine

The most advanced household manual sharpener today is the Apex type knife sharpener. Its appearance, device diagrams and the order of use are shown in Fig. Apex can be made to a continuously variable sharpening angle (pos. 2) or to fixed angles like Lansky-Metabo (pos. 3). Nominally, they work on Apex like on Lansky-Metabo (pos. 4), but other options are possible for more accurate sharpening, see below.

Homemade version of the Apex sharpener - Skomorokh knife sharpener

In 2016, in Runet, it made a noise, perhaps no less than the bubafony stove, the desktop modification of Ivan Skomorokhov's Apex, see fig. on right.

Sharpeners Skomorokh are much simpler than a prototype and are in no way inferior to it in functionality.

How to make a Skomorokh knife sharpener, see the video:

Not only knives ...

The original Apex sharpener is not very suitable for sharpening carpentry tools - chisels, iron planes. The Apex's sharpening angle floats for the same reasons as the Lansky-Metabo. Meanwhile, if the angle of sharpening of the chisel along the width of the blade "walks" by more than 1-1.5 degrees, then the tool strives to go sideways, crawl out or go deep into the solid wood along its fibers. It is very difficult to precisely and accurately select a groove for a tenon / ridge with such a chisel.

For sharpening carpentry tools, there are special devices, about which a special conversation is needed. Homemade products like a roller trolley sharpener, see fig. on the right, rather curiosities: not to mention the complexity, they require a stone or steel table, and, most importantly, they do not guarantee against the distortion of the blade on the donkey, which leads to the same undesirable result.

Meanwhile, 2-3 years ago, in one of the Chinese magazines on technical creativity, there was a glimpse of the Apex's refinement for sharpening, not inferior to that on a factory electric semiautomatic sharpening machine. The alteration is not difficult, see fig: the bar is set horizontally in level and the horizon of the bar is held along it, while sharpening. Within the angle of rotation of the rod in the horizontal plane 10-12 degrees to the right-to the left, the error of the sharpening angle is less than 1 degree. If the extension of the point of contact is from 250 mm, it is possible to sharpen chisels and glands of planers up to 120 mm wide.

In this operating mode, a (theoretically) zero sharpening angle error can be achieved by keeping the bar stationary, and moving the knife held by the magnetic holder, see above. Thus, it is possible to sharpen the glands of shaped planers, if you put a round in cross section, semicircular, elliptical or segmental touchstone in the clamps. The main thing is that the touch spot is always point-like.

... but also scissors

Another refinement of the Apex sharpener for sharpening scissors (also a necessary business in the household) is shown in Fig. on right. Total work - a couple of corner pieces or galvanized scraps and 4 additional holes in the sharpener table. About the process of making do-it-yourself attachments for sharpening scissors for the Skomorokh sharpener, see next. video:

Video: sharpening scissors, attachment to the Skomorokh sharpener

Finally, more about scissors

Check the hinge for looseness before grabbing poorly cutting scissors and putting them into the sharpener. Spread the scissors apart and look at them from the side. See, the tip is wrapped with a screw towards each other? Therefore, the scissors cut: the point of contact of the blades during cutting shifts from the roots to the ends. And therefore it is difficult to cut with scissors with the left hand: the turning of the ends is designed for the kinematics of the right. And if the hinge of the scissors is loose, the blades will go away from each other and will not even cope with the paper. In this case, you just need to tighten the riveted hinge with a hammer, and with a screw - with a screwdriver.

Greetings, Samodelkins!
Today I want to show you how it is possible from the materials that are (or at least should be) in almost every workshop, make an excellent device for smooth sharpening of knives.

Initially, the master wanted to buy a ready-made knife sharpener in China (namely, in the Aliexpress online store), but he thought why not try to make such a sharpener himself with his own hands. Moreover, the prices for this product from Chinese friends are rather big.

For self-production, you will need the following materials and tools:
1. Ordinary board;
2. Sandpaper;
3. Screwdriver;
4. Hammer;
5. Thick electrode 1 pc;
6. Electric jigsaw;
7. A piece of laminate;
8. Bolts and nuts;
9. Wooden handle;
10. Hex key;
11. Fluoroplastic or textolite (fiberglass).

Let's get down to making the sharpener itself.
First, take an ordinary board and cut a piece out of it. Then it is necessary to process the resulting wooden blank, namely to grind it with sandpaper.

It will serve as the basis for our homemade grinder.
In terms of size, it turns out we have 26 cm in length, the workpiece is 6.5 cm in width, and the height of the wooden base is 2 cm.

It is also necessary to make holes in this board. In total, this part of the future product will have 6 through holes. We drill 2 holes for the stand itself (more on it later). Next, we drill another hole of a smaller diameter, and also on the other side of the board we drill 3 more holes that will serve to fix the pressure plate.

Insert nuts into the holes made.

In the future, these nuts can be put on glue so that they do not fall out, but for now everything seems to be quite tight.
Then we will deal with the manufacture of the guide rack itself. Its master made from an ordinary thick electrode. It must be bent in half. Then, with the help of a hammer, the author beat off the entire upper part from the welding electrode and ground it. By the way, you can grind with an ordinary screwdriver. To do this, simply insert the electrode into the chuck of the screwdriver and, holding the sandpaper in your hand, grind the product.

At this stage, we insert the workpiece obtained from the electrode (guide post) into these two holes.
We do not insert at a right angle, but at a slight slope. The angle of the guide is anywhere from 65 to 70 degrees.

Everything sits down quite tightly, but also for greater reliability of our design, in the future it will be possible to put the guide post on epoxy glue, or on some other glue, or on something else.

But perhaps the master is mistaken and this is not fluoroplastic. Fluoroplastic is most often white and slippery of some kind. Most likely it is textolite or fiberglass. But in fact, this is not so important. The main thing is that this material is quite tough and does not wear off.
From this piece (PTFE or not PTFE), the author cut out a kind of pressure plate. He made holes in it, as well as small sweats, so that the hats go a little into the depth of the plate.

Then we put this plate on the wooden base made earlier. We fix it with screws.

The author took the cogs under a hex wrench. The master also made a small hole in the base of the future knife sharpener so that this key was always in this sharpener.

The whole thing is clamped and they (screws) are practically not visible on the plate.
But here, the master did not do the pot, since the sharpening part of the tool will not touch this screw.

Further, from the same fluoroplastic, the author made such a plate.

In this plate I made 2 holes for the same hex screw.
Further, the whole thing is put here and nestled with the help of a lamb.

Then the master made just such a guide for sharpening stones.

The length of the guide is 57 cm. Its author made it from a regular steel bar. I also cleaned it out. And on one end I put just such a handle (like from an old Soviet file).

You can also strengthen this connection by planting a wooden handle from a file on glue, but it has gone in quite tightly here itself, nothing falls out.

Regarding the fastening of the sharpening stones themselves. The author took a small piece of the clamp, cut it off and made holes. As a result, we got such little corners, two identical.

And here I put a nut with a threaded thread and a clamping screw.

The master also put a spring on the guide so that you can change the sharpening stones without unscrewing the nut with a clamping screw.

The sharpening stones themselves, or rather the base for these stones, were made by the author from an ordinary piece of laminate. Just by cutting it into strips.

The width of the strips is 2.5 cm, and the length is about 20 cm.

On the pieces of the laminate there are already ready-made grooves, in fact, where the corners of the guide part of the device will become.
Then the author glued sandpaper to the pieces of laminate with double-sided tape and signed which one was where. And, in fact, this is how it all happened:

The whole thing is put quite easily. With the groove of the laminate we get into one corner of the guide, and with the second corner we press the whetstone with the help of a spring.

Everything. Nothing falls out anywhere. Everything lies flat and pretty tight.
Let's continue to collect further our device. We insert the guide with the sharpening stone fixed on it into the hole prepared in advance for it, and you can safely begin the process of sharpening the knife.

The stroke is quite large due to the fact that here the author has removed a small chamfer on both sides.

A do-it-yourself knife sharpener is very useful in the household.

With the help of simple enough, you can sharpen cutting tools accurately and safely, which is simply necessary in the kitchen, fishermen and hunters, in the workshop.

Of course, a wide range of sharpeners are offered in stores, but homemade devices will save you unnecessary costs.

A dull knife is flour for the hostess when she cuts bread, prepares food, but cuts meat. Cutting is not only difficult for them, but also dangerous, because exactly blunt instruments are more likely to cause injuries... There is no point in proving the need for a sharp blade for a fisherman, hunter, shoemaker, etc. It is absolutely clear to everyone that the knife requires periodic sharpening. Another thing is how to provide it.

Many people use for these purposes means such as abrasive bars, emery wheels and sandpaper, files... Most often, for these purposes, abrasive or grinding stones are purchased, and the procedure itself is carried out "by eye". After such sharpening, the knife becomes sharp, but it also dulls quickly enough.

Why is this happening? The knife blade is made of various steels, has different thickness and sharpening parameters. The process of high-quality sharpening must completely restore the shape of the blade, and only in this case its sharpness will correspond to the planned standards.

Providing uniform sharpening without fixing the position and guiding elements is very difficult even for professionals. The task is much easier when using special devices that allow you to stabilize the processing mode (loads, directions, speed).

For mechanization of rather laborious work, it is better to use appropriate sharpening machines. Both fixtures and machines can be made by hand.

Basic principles of sharpening

When carrying out the correct sharpening of the knife, the main condition must be met - forming a sharp edge of the blade while maintaining its shape, which is ensured by removing the metal at a certain angle.

Turning is carried out with abrasive material, which has different grain sizes. Its choice is determined by the strength characteristics of the steel. Correct sharpening implies a certain order of work.

Sharpening angle

The effectiveness and quality of the measure under consideration is limited by the fundamental parameter - the sharpening angle. Depending on the purpose, the knives have the following meanings:

the smallest angle has a straight razor - (7-11) °;
fillet knives - (11-14) °;
kitchen knives for most products, incl. bread, vegetables, meat, etc. - (16-21) °;
hunting tools and knives for general technical purposes - (21-26) °;
universal hunting knives - (21-40) °;
a special tool that is used for cutting and chopping (for example, a machete) - (29-50) °.

The sharpening angle largely determines the thickness of the blade. At the smallest angles, it should resemble a razor, and at large angles, it becomes possible to make extra strong, massive knives.

Important. Holding the abrasive element and the knife itself in your hands, it is very difficult to provide a given angle along the entire length of the blade, which leads to uneven hand sharpening.

The main task of the adaptation is rigid fixation one of the elements and a clear direction of movement of the second element.

Types and selection of abrasives

To sharpen knives you need abrasive stone, which will provide the necessary metal cutting. Abrasive ability is provided by a certain amount of surface grain size, i.e. the number of abrasive grains per unit area. According to this parameter, the following stones stand out:

very coarse abrasives (international classification - extra coarse) - have a grain size of less than 260;
coarse (coarse) abrasives - 310-360;
medium (medium) abrasives - 390-510;
fine (fine) abrasives - 590-720. This is the main category of sharpening stones used for cutting knives;
very fine (ultra, extra fine) or grinding abrasives. They are used for turning razors and fine surface finishing of knives' blades.

By the nature of origin, abrasive stones are divided into natural or natural(corundum, shale) and artificial (ceramics, artificial diamond). In addition, rubber elements are sometimes used for fine finishing. When using abrasives, their surface moistened with water or soap-water solution(water tool) and oil(oil stones).

The shape of the abrasives can be round (discs) or rectangular (bars)... Bars are most often used, and they are selected so that the length significantly exceeded the length of the knife blade.

For complete sharpening of the tool, it is recommended to have 2 bars of medium and fine grain. It is better to complete the kit with a very small stone. The best option is the use of double-sided bars, in which one side has a medium, and the opposite has a fine grain.

Manual sharpening procedure

Any devices are designed to facilitate work and improve its quality, and the general procedure for manual sharpening remains the same:

The process begins with a coarse or medium-grained bar, which is laid on a plane. It is desirable to ensure its fixation.
The knife blade is brought to the abrasive surface at an angle equal to half the sharpening angle. The main task is to ensure the consistency of the angle throughout the event.
With a smooth movement with light pressure, the blade moves from the beginning to the end of the bar in the direction "away from you". The edge of the bar must always be perpendicular to the direction of movement of the blade. Do not allow the blade to break off at the end of the stone.
After reaching the edge of the bar, the movement is carried out in the opposite direction, while the sharp edge must constantly be on the surface of the abrasive. Direction change is provided by turning the handle.
The process is repeated until a burr appears along the entire length on the back of the blade edge. It should move to the opposite side when changing direction.
Next, a bar of medium grain size is taken, but with smaller grains. Sharpening continues, but the movements are carried out at first only "from oneself" until the appearance of a shine of metal on one side, and then the second side is also processed.
A block of fine grain is taken and the blade is processed until a mirror surface appears.
If a small burr remains, the sharpening is completed by using a very fine sanding stone. Some experienced people prefer to use instead of such a bar. leather belt... It perfectly polishes the knife blade.

Homemade devices

DIYers make sharpeners of various designs, but they all include 2 main elements - abrasive block and knife attachment mechanism... A ready-made abrasive block is best suited for the fixture, but you can also make it yourself.

To do this, sandpaper of different grain sizes is glued onto glass with a thickness of at least 4 mm. The connection can be secured with double-sided tape.

Fixed device

One of the simplest jigs is done from 2 wooden blocks of a triangular shape... They are fastened together with thumbscrews. An abrasive block is clamped between the wooden elements at the desired angle. This angle is set strictly along the protractor.

When turning a knife on such a device, the blade must be constantly held strictly vertical... Naturally, providing such a direction is much easier than constantly guiding the knife at an angle.

Movable structure

To improve the quality of sharpening, it is necessary to fix not only the abrasive, but also the knife. Such a device can also be made by hand. It is collected on a flat, horizontal, massive surface. The device consists of 2 parts - rigidly fixed abrasive bar at the desired angle(similar to a fixed structure) and trolleys on wheels(rollers) with a horizontally fixed knife.

The cart moves manually along the guide rail. The hand is provided and light pressure on the blade to the abrasive surface. This ensures the correct sharpening angle and eliminates the need for manual guidance.

Changing direction can be done in different ways. The easiest is to make a trolley with wheels at the top and bottom. At the end of the bar, the trolley simply turns over.

Point machine

Sharpening machines have a more complex design, which allows you to change the sharpening angle. There are several options for a constructive solution:

A knife is fixed on the platform with the possibility of adjustment. It is set at the required angle and fixed permanently. The abrasive bar is mounted on a movable bar mounted on a vertical support. He moves strictly horizontally. Sharpening is provided by moving the abrasive relative to the knife blade.
It is fixed on a fixed frame, but the bar can be displaced along the guide to set the desired sharpening angle. The knife is installed in a movable table, and is fixed with a magnetic holder, which makes it possible to turn it over.

DIY example

As an example, we can cite the technology of self-production of a grinding device - an analogue Lansky sharpeners... It has a standard design.

The knife is fixed on the horizontal base, and its fastening provides magnet... The emery element is located on a rod along which it can move perpendicular to the knife. The guide rod is installed in the holes of the vertical post.

These holes are drilled at an angle to the surface of the post and thus define a certain angle to the bar. Several holes are drilled vertically in the rack, and by rearranging the guide, you can still change the sharpening angle.

Manufacturing devices are carried out in the following order:

On the base plate (, board, sheet metal) with the edge slats are installed limiting the displacement of the knife in the transverse direction. One of them is fastened in the slots on screws with a "thumb" for fixing knives with different blade widths. In the center of the area where the knife is located, the magnet.
The emery bar is fixed on two pieces of the corner, which are held together by pins. Holes are drilled on both sides of this part for installation on the rod.
Steel rod with a diameter of 10-15 mm is passed through the indicated holes, and at the end is installed limiter to avoid the fall of the bar. The other end is sliced thread.
On an aluminum U-shaped profile with a width of 30-50 mm, 5-6 holes are drilled with a diameter 1-2 mm larger than the diameter of the rod. The holes are drilled at an angle corresponding to the sharpening angles, taking into account the height of the position on the rack.
The rod is installed in the desired hole and fixed bolts.

Such a device works in the following way:

the knife is fixed on the base and attracted by a magnet;
a bar of the desired grain size is installed on the sharpening element;
the rod is fixed in the desired hole on the rack;
by hand, the bar moves along the rod, processing the blade, and the movement is carried out "from oneself" and "toward oneself";
with the other hand, the knife gradually moves in the longitudinal direction.

Watch the detailed drawings, description and illustrations of the knife sharpening device with and without a magnetic holder in the video below:

Scissor sharpener

With the help of attachments for knives, you can also sharpen scissors, but such an event has its own specifics... The sharpening angle is within (60-74) °. Tailoring scissors usually have an angle of (72-74) °. The cutting part at the point of contact of both parts is flat, and the bevel is performed on one side. Main sharpening carried out from the outside, beveled side... The inner surface is only sanded with a fine stone.

The process is carried out in this order:

Disassembly of scissors... To do this, unscrew the screw that holds the halves together and carefully disconnect them. A minus screwdriver is used.
With the help of a coarse abrasive, sharpening at the right angle... Movements are made only in one direction - "towards yourself". Half of the scissors are held by the ring and turning begins at the tip of the blade.
Using small block, carried out fine-tuning.

Some scissors cannot be disassembled. They can also be sharpened, for which they open up as much as possible. The halves are sharpened alternately.

How to check the sharpness?

There are several popular ways to check the quality of sharpening knives:

Paper... Take a sheet of paper (for example, for a printer) and cut a strip at the edge. If the knife is soaked well, then the strip is easily cut and has smooth edges. A dull knife crushes the edge and cuts unevenly, with rags.
A tomato... A sharp knife cuts a tomato in half exactly, and a blunt knife crushes it.
Arm hair... A sharp blade works like a razor and cuts off hairs, and a blunt tool only crushes them.
The sharpness can be checked finger keeping caution. Burrs indicate poor workmanship. Absolutely flat edges indicate quality work.

Knives have a tendency to dull, which interferes with their use. Sharpening devices and machines will help solve the problem by ensuring the correct sharpening of the blade, restoring the specified angle. There are many designs of simple little scissors, and the owner himself must decide which one to choose.

Every man in the house will benefit from a convenient sharpening machine. After all, the owner is often judged by how sharp this kitchen tool is.

There are many techniques for sharpening knife blades. For example, for a process carried out at home, only a turning block or ready-made devices with an angular gap shape will be sufficient.

To repair expensive hunter knives, European manufacturers produce devices in the form of hard bars, the basis of which is a high-strength alloy.

This article will describe how to make a do-it-yourself knife sharpening machine.

Why are knives dull?

What is the reason why the knife becomes dull when cutting? This can be explained by the fact that abrasive particles, which are present in the cut material, have a negative effect on the cutting edge. For example, they are present on vegetables, paper. In simple terms, the blade is subject to gradual wear.

The next reason is the inability to hold the blade in the desired position constantly. Any tremor of the hand causes the knife to tilt, which entails a lateral load.

Sharpening technique

The sharpening technique consists in unified, but at the same time rather laborious methods. The main task is to repair the damage to the blade. It should be noted that for many, such a procedure as sharpening knives provides a good mood and peace of mind.

The basic rule in this process is to maintain a precisely defined constant angle. Strength is not required here. The main thing is that the bar and the blade meet at a certain angle. This is the basic rule of sharpening technique.

What do you need to do to maintain a constant angle?

In order for the angle to have a constant indicator, there are two ways. The first is to acquire the sharpening skill. The angle indicator can be controlled using a conventional marker. They should paint over the carts and, after several sharpening cycles, see how the paint is preserved. If it has worn off unevenly, then the blade is not well processed.

If the knife being sharpened is decorative, then glue the blade with tape so that only the cutting edge remains open. Even if you unsuccessfully guide your hand, there will be no scratches on the blade.

An important point is that the direction of the blade along the bar is perpendicular to the edge at the points of contact. This is actually quite difficult to accomplish. It is acceptable that the angle between the edge and the blade is less than 90 degrees. But when directed along the cutting edge, this indicator is not suitable.

The abrasive particles of the bar can leave grooves on the blade that will never sharpen, but will play a positive role during cutting. If the grooves are aligned along the cutting edge, they will not be useful in cutting. The worst thing is that the cutting edge can break off altogether.

It is important that the bar is long. It should be one and a half or two lengths of the blade. It is allowed for a diamond block to be somewhat shorter, as it grinds faster and better. Its width does not play a significant role. If it is wider, then it is more convenient to work on it and there is less chance of getting the blade outside the device. This can damage the side surface or the blade.

Homemade knife sharpeners come in a variety of designs. All that is required from the manufacturer is the availability of the right material and skills in working with the tools.

The principle of operation of such a device as a manual machine for sharpening knives with your own hands is to hold the knife blade in an upright position and drive it along a bar fixed at the desired angle. This is much easier than placing a sharpening bar horizontally and holding the knife at the correct angle.

In order to make a do-it-yourself knife sharpening machine, you need a piece of laminate, a wooden rail, sandpaper and a couple of bots with lambs. Chipboard or plywood can serve as a substitute for laminate.

To make a knife holder, you need to cut off part of the material. To prevent the block from touching the holder when sharpening, you should clean its edge at an angle using emery.

It is necessary to mark and cut off the top of the vertical post, which will serve as a support for the bar. The angle is chosen two times less than that with which the knife will be sharpened. For kitchen knives, it is recommended to take an angle of 10-15 degrees.

A do-it-yourself knife sharpening machine, the drawings of which are deliberately drawn up, assumes the correct calculation of the length of the base of the racks. Please note that the height indicator will be affected by the subsequent installation of the cross support. After that, all parts are cut off, and the edges are cleaned.

Holes are marked and drilled in the base and plate to hold down the bolts that hold the blade. When marking, the distance of the holes from the edge of the base is maintained. This is necessary for the versatility of the device, since all knives have their own width. The pressure plate is bolted.

The uprights are secured with screws. The moment that the load on the bottom is small is also taken into account. In this case, it is better to resort to using thermal glue. In exactly this way, the horizontal bar is attached. The sharpener is almost ready. It remains to make a bar.

For its manufacture, a rail of the required length is cut. Sandpaper with the desired size of abrasive is glued to one edge. To optimize the result, you can resort to making several bars with different grain sizes. The best range is P600 - P2000. In order to protect your hands from cuts, you need to screw the handle on the top of the rail.

The result is a homemade do-it-yourself knife sharpening machine, characterized by high functionality and practicality. When working, the device rests against the edge of the table, which is quite comfortable when using it.

A machine for sharpening knives with your own hands is of a different type. In this case, it is based on a threaded rod M8. Two large washers and nuts are used to hold the 200 mm long bar.

Closes the thread. A pair of paper clips serve to hold the rail stand at the desired height. This ensures smooth adjustment of the sharpening angle. The base is made of a beam, the thickness of which is 40 mm. It is supported by a hand.

How to sharpen planing knives with your own hands

Every owner who has a plane or a planer, probably faced the problem of sharpening their knives. It is expensive to purchase new ones periodically. Knives can be sharpened with ease with your own hands. In this case, specialized machines are used, or if it is used constantly, then it would be better to make a machine for sharpening knives with your own hands.

DIY planer knife sharpening machine

To sharpen the planer knife, use special grinding equipment. The do-it-yourself knife sharpening machine has a compact size. It can be installed in a garage or on a personal plot.

Many are interested in how to make a machine for sharpening knives with their own hands. To make the device, you need to find certain parts. Perhaps such parts are lying around in your shed or garage. They can also be purchased online.

The do-it-yourself planer knife sharpening machine consists of:

faceplates;
table;
engine;
vacuum cleaner;
casing.

First of all, you should find a faceplate. This is the most important component of the future equipment. It is she who is responsible for the sharpening process. The jointer knives are narrow, and the faceplate serves as a guarantor of complete and safe sharpening. This part will have to be bought new, but the rest can be used with the old ones.

It is better to purchase faceplates of German or American production. The average cost of a part is 25,000 rubles.

The next step is to find an engine, the power of which should be 1-1.5 kW. It is not necessary to buy it. Anyone will do, even from an old washing machine. But a table, a casing and a vacuum cleaner will surely be found in everyone.

The main stages of manufacturing the device

When the table is selected, the engine is anchored directly below it. A faceplate is attached to the driving part. The engine should initially be equipped with a button that enables the unit to turn on and off. It should fit comfortably.

For reliable protection, the faceplate is closed with a square-shaped casing with one cut-out corner. It is this area that needs to be sharpened.

On the lower surface of the table in the area of the sharpening passage, a hole is made of the same diameter as that of the vacuum cleaner hose. The presence of a vacuum cleaner is not essential, but it is advisable to install it. It removes unnecessary dirt from the blade processing.

What do you need to know?

Mounting the motor under the base of the faceplate is optional. You can make the parts connect with a belt. In this case, the design will be complex.

The do-it-yourself jointer knife sharpening machine is also suitable for saws and axes.

Sharpening the ice screw

Sharp blades of an ice screw enable the fisherman to quickly make holes in the waters of the ice of reservoirs. However, over time, any cutting tool becomes dull and requires sharpening.

For fishermen, a quality ice screw is a great pride. Often, true competitions in the speed of drilling ice holes are held on reservoirs. And not always the victory smiles at young and strong fishermen who are armed with imported devices. There are times when experienced fishermen equipped with simple Soviet-made tools turn out to be the winner in the competition. The reason for the high speed of drilling the hole lies in the good sharpening of the knives and the correct setting of the device. Newbie anglers, having bought new Swedish devices, do not even have time to blink an eye as their knives become dull. The smallest grains of sand and pebbles in the ice contribute to the formation of chips and gouges on the blade.

Sharpening of devices is carried out in a variety of ways. Many of our ancestors did not even know what a professional is. In most cases, sharpening was carried out using hand-made devices.

Homemade ice screw machine: what is needed to make it?

For the manufacture of a device such as a knife sharpening machine, you will need two strips of steel, the thickness of which is 4 mm, the width is 60 mm, and the length is 200 mm. A spring from a car is often used as a strip. But it is very difficult to bend.

Working process

First, you need to make the device case. The steel strips are bent so that the chamfers of the knives pressed against the ends of the arc are not only parallel, but also in the same plane.

After making the arc from the same steel strip, the pressure plate is bent, which serves as a lock for the sharpened knives

Holes are drilled in the housing and the pressure plate for M12 or M14 bolts. Having pulled the body and the pressure plate by means of a bolt and a nut, we clamp the knives between them and check the strength of their adhesion to the surface of the end of the emery circle.

If the knives are not at the required angle (the chamfers do not adhere exactly to the circle), then the device is modified by bending the body arc to the appropriate level. If the knives are positioned correctly, then the structure is disassembled, and stiffeners are welded to the arc of the body on both sides.

Sharpening of knives is carried out better on which rotates horizontally. In this case, when the knives are wetted with water, the latter remains on the blade and stone longer, ensuring their safety. Submerge your knives in the water more often. This will help prevent overheating of the steel.

Minus device

The disadvantages of the device include the impossibility of sharpening knives with different angles of the cutting chamfer. But each manufacturer of ice augers offers its own models. In this case, a universal device will do.

Making a universal device for sharpening an ice screw

The universal design allows you to sharpen knives at any angle of the cutting edge. By smoothly changing the angle between the arms of the unit, on which the knives are fastened with screws, it is possible to fix the desired position of the knives in relation to the plane of the grinding stone.

To make this device, you need to find a door shed with minimal backlash, as well as an M8 or M10 screw with its own nut. Holes are drilled in the shoulders of the canopy. Their diameter is 6-7 mm (for attaching knives to them by means of screws).

A fixing plate with a slot for the fixing screw is made from a steel strip, the thickness of which is 3 mm. The plate and screw are welded to the canopy arms.

It happens that knives are sharpened, the location of the holes of which does not correspond to the holes in the canopy. In this case, additional holes are drilled in the shoulders for non-standard knives. In this case, the device has greater versatility.

How are planer knives sharpened?

Gadgets such as planers and planers are often seen in country houses. Through them, raw lumber is brought to the desired state. The knives of these devices, like any others, are dull. If you use them often, then the best solution would be to sharpen planer knives with your own hands. For the manufacture of grinding equipment at home, various materials are required: metal, aluminum or wood.

The knife holder can be made from a piece of wood. Having made cuts at 45 degrees using a circular saw, you can sharpen the knives with a belt sander or a large bar. If the latter is not there, then sandpaper is attached to a smooth surface made of metal, wood, chipboard or glass.

Knife holders can be made from scrap materials. The best solution would be to use metal corners that have an indicator of 90 degrees. When placing two knives on the sides, the sharpening angle of each will be 45 degrees. With the help of screws, you can fix the knives with the second corner.