How to make a device for sharpening kitchen knives. What is a do-it-yourself knife sharpening device?

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They say that “the need for invention is cunning.” But we in the editorial office love people who know how to see simple things hidden potential and come up with more and more new purposes for them. And not even for the sake of wanting to save money, but just because. To entertain the mind. For example, like the hero of today’s review, who was able regular clothespins turn into a mini-set of useful household tools.

Popular life hacker ShakeTheFuture clearly the type of person who can think outside the box. After all, how else could one make a pair of clothespins and an old pencil sharpener such unexpected things? For example:

1. Wire cutter

Need to strip a wire? The simplest will help you do this simply and safely homemade instrument. Unscrew the blade from the pencil sharpener and screw it into the center of any wooden clothespin as in the photo. Now you can easily, literally with one movement, remove the plastic insulation from the cable.

2. Stationery knife

We make another tool from the same components. Remove the blade from the sharpener and disassemble the clothespin. You will need two wooden halves. Just glue the blade to one of them, and then glue it to the second. The stationery knife is ready in three minutes!

3. Scraper or razor

All “spare parts” are exactly the same. But now you will need a blade and only one of the wooden halves from the clothespin. Cut it a little lengthwise at the top, insert the sharpener blade inside and glue it securely. Now you have a scraper or even a simple razor at your disposal.

The introduction of the Edge Pro sharpening machines was, without exaggeration, a revolution. The prices are really high, but no one is stopping you from copying the principle and creating a similar device yourself. We offer design simple machine for sharpening knives, chisels and any other blades that you can make with your own hands.

Machine base

Most parts for a sharpening machine can be made from literally anything by following general principle devices. As an example, let's take laminated or polished box plywood 8-12 mm thick, which was widely used in the manufacture of Soviet radio equipment housings.

The base must be heavy - about 3.5-5 kg - otherwise the machine will be unstable and unsuitable for sharpening heavy chopping tools. Therefore, the inclusion of steel elements in the design is welcome, for example, the base of the case can be “forged” with a 20x20 mm angle.

From plywood you need to cut out two parts in the shape of a rectangular trapezoid with a jigsaw with bases of 170 and 60 mm and a height of 230 mm. When cutting, leave an allowance of 0.5-0.7 mm for processing the ends: they must be straight and exactly match the markings.

The third part is an inclined plane made of plywood boards measuring 230x150 mm. It is installed between the inclined sides of the side walls, while the trapezium of the side walls rests on the rectangular side.

In other words, the base of the machine is a kind of wedge, but the inclined plane should protrude 40 mm from the front. At the ends of the side walls, use a surface planer to mark two lines with an indent of half the thickness of the plywood. Drill three holes in each board to fasten the parts with screws. Transfer the drill bit to the ends of the inclined part and temporarily connect the base parts.

At the rear, the side walls are connected by a 60x60 mm block, which is secured to the end with two screws on each side. You need to make a 10 mm vertical hole in the block with an indentation of 50 mm from the center, that is, 25 mm from the edge. To be sure of verticality, it is better to first drill with a thin drill on both sides and then expand. Screw two fittings with M10 internal thread into the hole from the top and bottom, and in them - a 10 mm pin with a length of 250 mm. Here you may need to slightly adjust the bottom fitting if its threads do not line up with the stud.

Tool support device

Remove the flat inclined part from the base - it needs to be modified by equipping it with a device for fixing and pressing the tool being processed.

First, set aside 40 mm from the front edge and along this line, use a matching hacksaw to file a groove about 2 mm deep. Using a sectioning knife or a shoemaker's knife, chop off the two top layers of veneer from the end of the board to form a recess into which you can insert a 2 mm steel plate flush with the common plane.

The handrail consists of two steel strips 170x60 mm and 150x40 mm. They need to be folded together along the long end with even indentations along the edges and make three through holes by 6 mm. The strips along these holes need to be tightened with bolts, placing the caps on the side of the upper, larger plate. Use arc welding to bake each cap, welding it to the plate, then remove the beads of metal and grind the plate until a perfectly flat plane is obtained.

Attach the narrower striker plate to the notch on the edge and transfer the holes with a drill, then secure the rest with bolts. It can also be magnetized before installation DC, this will help in sharpening small blades.

Locking mechanism

The second part of the tool rest is the clamping bar. It is also made of two parts:

The upper L-shaped bar is 150x180 mm with a shelf width of about 45-50 mm.
The lower strike plate is rectangular 50x100 mm.

The parts need to be folded in the same way as the parts of the tool rest were folded, placing the counter plate at the far edge of the upper clamping area. We make two holes in the center with a distance of 25 mm from the edges of the small part, and through them we tighten the parts with two 8 mm bolts. They need to be wound in opposite directions, with the head of the upper (near) bolt located on the side of the clamping bar. The bolt heads are also welded to the plates and pre-ground to obtain neat roundings.

On an inclined board with an indentation of 40 mm from the edge, draw a line with a thickness planer and make one 8 mm hole 25 mm from the top and bottom edges. Connect the edges of the holes with markings and use a jigsaw to make a cut with an allowance. Finish the resulting groove with a file to a width of 8.2-8.5 mm.

Fasten the clamping and strike strips through the groove in the board. Tighten the bolt protruding from above with a nut so that the bar maintains minimal movement, then secure the connection with a second nut. To press or release the strip from below (in the niche of the base), screw a wing nut onto the second bolt.

Adjusting the sharpening angle

Throw a wide washer onto the pin screwed into the base bar and tighten the nut so that the rod does not rotate in the fittings.

The adjusting block must be made from a small block of hard material measuring approximately 20x40x80 mm. Take carbolite, textolite or hardwood.

15 mm from the edge of the block, we drill a 20 mm end on both sides, the hole expands to 9 mm, then we cut a thread inside. A second hole is drilled at a distance of 50 mm from the axis of the hole made, but in the flat part of the part, that is, perpendicular to the previous one. This hole should have a diameter of about 14 mm, in addition, it needs to be flared strongly with a round rasp.

The block is screwed onto a pin, so it is possible to relatively accurately adjust the height of the eye without complex system screw clamps as in the original machine, which in practice is a little more difficult to implement. In order for the block to remain stationary during operation, it must be secured on both sides with M10 wing nuts.

Carriage and replacement bars

For the sharpening carriage, you will need to coaxially weld 30 cm sections of an M10 pin and a smooth, even rod 10 mm thick. You also need two solid blocks measuring approximately 50x80 mm and up to 20 mm thick. A 10 mm hole should be made in each bar in the center and at a distance of 20 mm from the top edge.

First, a wing nut is screwed onto the rod, then a wide washer and two bars, again a washer and a nut. You can clamp rectangular sharpening stones between the whetstones, but it is better to make several replacement sharpening stones.

As a basis for them, take a light aluminum profile with a flat part 40-50 mm wide. This can be a profile rectangular pipe or sections of an old cornice profile.

We sand and degrease the flat part, and “Moment” glue strips of sandpaper of different grain sizes from 400 to 1200 grit onto it. Choose a cloth-based sandpaper, and glue a strip of suede leather onto one of the bars for straightening the blades with abrasive paste.

How to sharpen correctly

For correct sharpening make several templates from plywood with angles of 14-20º for cutting edges and 30-37º for chopping edges, exact angle depends on the steel grade. Fix the blade parallel to the edge of the tool rest and press it with a bar. Using the template, adjust the angle between the planes of the sharpening block and the inclined board of the table.

Start sharpening with a large (P400) whetstone if the edge does not have the correct angle. Make sure that the descent strip takes the form of a straight strip without bends or waves. Reduce the grit and go along both sides of the blade first with a P800 stone, and then with a P1000 or P1200 stone. When sharpening the blade, apply the whetstone with slight force in both directions.

After sharpening, the blade needs to be straightened with a “leather” whetstone, onto which a small amount of GOI paste has been applied. When editing blades, the working movement is directed only towards the edge (towards you), but not against it. And finally, little advice: if you sharpen knives with polished blades and engraving, cover them with masking tape so that the crumbling abrasive does not leave scratches. It also wouldn’t hurt to cover the surface of the tool rest with vinyl self-adhesive.

With the help of a knife we prepare food, cut food and perform other housework. Therefore, it is very important that the knife blade always remains sharp. Theoretically, there is nothing difficult in sharpening knives, but in practice it turns out that not everyone can sharpen a blade well. To have an idea of what to sharpen knives with and how to do it correctly, we recommend reading our article.

Before you start sharpening a knife, you need to find out what material it is made of. There are several types of knives:

- Carbon steel knives are the most affordable, made from an alloy of iron and carbon, easy to sharpen and remain sharp for a long time. Among the disadvantages, it can be noted that the knife blade oxidizes from interaction with food or an acidic environment, due to this, rust and stains appear on the knife, and food acquires a metallic taste. Over time, after plaque forms on the blade, oxidation stops.

- Low carbon knives of stainless steel- made from an alloy of iron, chromium, carbon and in some cases nickel or molybdenum. Stainless steel knives are inferior in hardness to carbon steel, so they quickly become dull and require regular sharpening. The advantages include corrosion resistance.

- Knives made of high-carbon stainless steel are a higher class of knives, with a higher carbon content and additions of cobalt or vanadium. Due to the higher quality alloy, this type of knives does not require frequent sharpening and is not subject to corrosion.

- Damascus steel knives are mainly made as edged weapons, but there are also kitchen options. Damascus steel knife is a multi-layer blade made of different alloys High Quality. The disadvantages include the high cost of knives.

Ceramic knives have gained popularity due to their sharpness and ability to long time don't be dumb. But besides the advantages, Ceramic knives have a significant disadvantage, which is their fragility when dropped from a height and poor resistance to fracture.

Sharpening tools

Touchstone (sharpening stone)

Sharpening stones are available with different amounts of abrasive grains per square millimeter. Therefore, for rough sharpening and finishing grinding, you need to use bars with a minimum and maximum abrasive content. In the touchstones foreign production information about the number of abrasive grains is on their labeling. Sharpening stones domestic production you have to choose “by eye” or ask the seller which whetstone to use for initial sharpening and which for final sharpening.

Mechanical sharpener

Mechanical sharpeners are mainly used for sharpening kitchen knives. Although the sharpening process is quick, the quality leaves much to be desired. For this reason, for hunting and sporting knives, it is recommended to use other sharpening methods.

Electric sharpener

Modern models electric sharpeners allow you to achieve high quality sharpening due to the built-in function of automatically determining the angle of the blade. The electric sharpener is great for both household use, and for sharpening knives in catering establishments. The lineup electric sharpeners presented in wide range, so the price may vary, but if you want your knives to always remain sharp, then buy more “advanced” and expensive models.

Musat

Musat - designed to maintain the sharpness of the knife edge. In shape, the musat resembles a round file with a handle. Musats are included in knife sets, and many owners often confuse them with a tool for fully sharpening a blade. Please note that with the help of musat you can maintain the sharpness of a sharpened knife, but if the knife has become completely dull, you will not be able to sharpen it with musat.

Sharpener "Lansky"

This sharpener is used for sharpening small and medium-sized knives. The design of the sharpener allows you to sharpen the blade at the angle you choose. The Lansky sharpener consists of a rod with a removable touchstone and two corners connected to each other. The corners simultaneously serve as a vice for the knife and a scale for selecting the sharpening angle. The sharpener kit also includes sharpening stones of different grits with ANSI markings.

Sharpening and grinding machines

Sharpening machines are used mainly in production for high-precision sharpening of rotating shaft blades. In addition to high-precision machines, there are abrasive wheels With electric drive and rotating discs for grinding. Sharpening knives on such machines should only be done by an experienced craftsman, because due to the speed of rotation of the circle or disk and high temperature heating, with any unsuccessful movement, the knife blade will become unusable.

Do-it-yourself blade sharpening

Sharpening a knife using a whetstone

Sharpening of a blade made with a sharpening stone is considered to be of the highest quality, of course, provided that it was carried out by experienced master. To sharpen a knife on a whetstone, do the following:

1. Place a low abrasive grit sandstone on a stationary surface. If the block is small, it can be clamped in a vice.

1. Holding the knife at an angle of 20-25 degrees relative to the surface of the block, begin moving the knife along the whetstone with the cutting edge forward.

Move the blade along the block so that during movement it touches the surface of the whetstone along its entire length.
As you move, try to maintain the same blade angle.
After making 2-3 movements, turn the knife over and repeat the sharpening process on the other side of the blade.
Thus, alternating sides, sharpen the knife until an edge (burr) appears along the edge of the blade.
Swap the coarse whetstone for a grinding stone.
Sand the knife blade until the edge disappears.
Test the sharpness of the knife by cutting a hemp rope folded several times, or try cutting a sheet of paper.

How to sharpen a knife using a sharpening stone, see also in the video:

Sharpening a hunting knife on a Lansky sharpener

Hunting knives are made of hard steel, so their initial sharpening requires sharpening stones with a low content of abrasive grains.

Clamp the knife in a sharpener vice.
Place a sharpening stone with a low content of abrasive grains on the rod.
Select the angle of the block (for hunting knives it is usually from 20 to 30 degrees).
Insert the rod into the desired hole.
Lubricate the whetstone with the special oil included in the sharpener kit.
Start moving the block along the knife blade, from the base to the tip.
Flip the sharpener over and repeat the process on the other side of the knife.
Once the edge is formed, change the stone and do the final sanding.
Because the Hunter knives are mainly made with a double-sided blade, then after finishing sharpening on one side, change the position of the knife in the vice and begin the sharpening process on the other side.
Once you've finished sharpening, polish the knife blade with felt.

How to sharpen knives in a Lansky sharpener, watch the video:

Sharpening scissors

Sharpening of scissors must be done on a special sharpening machine. Sharpening blades using improvised materials (sandpaper, the edge of a glass, etc.) can temporarily improve the sharpness of scissors, but not for long. If you do not have the opportunity to sharpen scissors from a professional, you can try self-sharpening on an abrasive stone. When sharpening you need to follow a few simple rules:

The sharpening stone should be fine-grained.
The blade is sharpened over the entire surface of the edge at the same time.
The angle of the blade should match the factory edge.
The movement of the blade along the stone should be from the screw to the tip.
Scissors need to be sharpened disassembled.

When sharpening scissors, do not rush; patience will be your ally in this matter.

You can also watch the video on how to quickly sharpen scissors:

Sharpening plane and chisel blades

Sharpening the blade of a plane and a chisel are practically no different from each other. Therefore, the sharpening process described below applies to both tools:

Place the chisel on the whetstone at an angle of 30-40 degrees.
Holding the chisel with your hand, fingers free hand press the chamfer against the touchstone.
Start running the chisel over the whetstone until a burr forms on the smooth side of the chisel.
Change the whetstone to a fine-grained one and do the final grinding of the chisel.
Check the sharpness of the chisel blade by removing shavings from the corner of the block.

Besides manual sharpening, the chisel can be sharpened on a machine with a rotating abrasive disk:

Turn on the machine and let the disc reach full speed.
Holding the chisel with both hands, place its bevel against the sharpening wheel.
Be sure to maintain the angle of the chisel, otherwise you will damage the blade of the tool.
Do not press the chisel with great force and do not hold it on the blade for too long, this will lead to overheating of the metal and destruction of the blade.
While sharpening, wet the blade with water.
The final grinding of the chisel blade is best done by hand, using a fine-grained stone or sandpaper.

Do not forget that when sharpening products on a machine, a lot of sparks and small particles are generated that can get into your eyes, so be sure to wear safety glasses. To avoid damaging your hands on the rotating disk, wear gloves.

You can also learn how to sharpen tools from the video:

Tips for quickly sharpening a blade using improvised tools

Stone

You can quickly sharpen a knife on a hike or at a picnic using an ordinary cobblestone. Use any stone lying on the ground instead of a whetstone and run the knife blade along its surface. You won't achieve razor sharpness, but you will return the knife to working condition.

Second knife

Sharpen two knives at once, without sharpening stones and devices, it is quite possible. To do this, you need to take a knife in both hands and begin to sharpen the blade of one knife on the blade of the other. After 5-10 minutes of this work, the knives will become sharper than before.

Glass objects

The knife blade can be slightly sharpened on the rough edge of glass or ceramic objects. For example, about the bottom of a glass or the edge tiles. The main thing is that the surface is rough.

Leather belt

A leather belt is more suitable for finishing and shaping a knife blade razor sharp than for rough sharpening. But if there is nothing at hand except a belt, then you can try to sharpen the knife on it. To do this, you need to tighten the belt and start moving the blade along it; you may not achieve strong sharpness, but you will polish the knife to a shine.

By learning to sharpen knives and tools yourself, you will acquire a skill that will be useful to you throughout your life!

The most simple variation sharpening – homemade device from wooden and abrasive bars. To make it, you will need two bars of each type - they must be strictly the same dimensions. Wooden products must be pre-treated sandpaper to remove all burrs from their surface.

The manufacturing procedure itself will not cause any difficulties. First, mark the wooden blocks: taking into account the required sharpening angle of the knives, draw lines for future fastenings of abrasive workpieces. Then apply sharpening stones to the resulting lines and mark their width on the wood. The next step is the cuts: make them according to the markings on both wooden products cuts of the required slope and depth of 1-1.5 cm. Insert abrasive stones into the recesses and secure them with bolts.

Advice. To prevent the resulting device from slipping on the surface while servicing the knives, attach a rubber gasket to it from below - it will give the device the necessary stability.

Massive sharpener on a stand

A more complex variation of the knife is a stand with a separate support and a sharpening rod attachment. To make it you will need:

chipboard sheet;
a block of wood 8 cm long and 2x4 cm in cross section;
steel rod M6 or M8;
plexiglass 6x12 cm;
magnet with holes for fasteners;
self-tapping screws, bolts, wing nuts;
wooden clamps;
rubber feet;
saw and drill.

Sharpener construction diagram:

Cut three blanks from the chipboard sheet: 7x8 cm, 8x30 cm and 12x37 cm.
On the oblong side of the workpiece 8x30 cm, 6 cm from the edge, make a hole.
Drill holes for the legs in the corners of the 12x37 cm workpiece.
Drill two through perpendicular holes in wooden block: the first is 3 cm from the edge, the second is 3 cm from the first. From the edge of the product to the first hole, cut a 1 cm thick recess.
Make a slot in the center of the plexiglass strip.
On a workpiece 12x37 cm, at a distance of 4 cm from the edge, secure the workpiece 7x8 cm perpendicularly with two self-tapping screws. Fix the workpiece 8x30 cm on top with self-tapping screws.
At the highest point of the installed workpiece 8x30 cm, drill a small recess and fix the magnet in it with self-tapping screws. Place plexiglass on the same blank - fasten the products with a bolt through the previously made hole and slot.
On any edge of the 12x37 cm workpiece, drill a hole for a steel sharpening rod and secure it there with a wing nut.
Place the block on the rod, securing it with a bolt and nut.
Using a rod, nuts and two clamps, assemble a knife holder.
Screw the legs to the finished stand.

How to sharpen a knife correctly?

To achieve high-quality results, it is not enough to build one of the above-mentioned devices - you also need to master the rules of manual sharpening and understand the order of work.

First, the required sharpening angle of the tool is calculated - it must be maintained throughout the entire sharpening process. Next, using smooth movements alternately “from yourself” and “towards you”, begin to move the blade along the sharpening element - an abrasive or a rod. In one movement it should go along the sharpener from edge to edge. In this case, movements are performed perpendicular to the edge of the blade.

Important! At the end of each pass, the blade should remain on the sharpener and not tear off, otherwise you can not only dull the knife even more, but also deform its side surface.

Move the blade along the sharpener with one side until it reverse side If a burr does not appear, then turn the knife over and begin sharpening the other side of the blade in the same way. Continue sharpening alternating sides until the burrs are completely gone. Gradually reduce the pressure of the knife.

How to determine the sharpening angle?

The most important parameter for sharpening a knife is the required blade angle. It depends on the scope of application of a particular tool and the range of tasks assigned to it:

Any type of razor – angle 10-15 degrees.
Fillet knife – 15 degrees.
Knife for fruits, bread and vegetables – 15-20 degrees.
Multifunctional tools for slicing food – 20-25 degrees.
Hunting knives - 25 degrees. Such blades are designed for cutting not only soft products, but also wood, bones, and fabrics.

Utility knives general purpose– 25-30 degrees.
Tourist and camping knives – 30-35 degrees.
Cutting knives hard materials– 30-50 degrees. The greater the sharpening angle, the worse such a knife cuts food, but the better it copes with wood, trunks, and plastic.

Please note that there are also combination knives: they are divided into several zones with different angles sharpening. The advantage of such tools is versatility, the disadvantage is the complexity of maintenance.

So, assembling a knife sharpening device yourself is an excellent way out of a situation where you don’t want to buy a professional device or regularly contact craftsmen to service the tools. You have two options for making sharpeners different levels complexity - choose which one you can handle, and use it strictly according to the indicated rules, so that the sharpening is not only of high quality, but also safe.

DIY knife sharpener: video

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