How to sharpen a knife correctly at the apex

How to sharpen knives with your own hands?

A knife is used to cut up food, remove skins from killed animals, cut soft materials, and much more. However, over time, the cutting edge becomes unusable. To restore its sharpness, it is necessary to carry out processing. Sharpening knives is a separate technological process that is easy to do yourself.

Main types of blades

Before you start learning how to sharpen blades, you need to know what types of blades there are. Different types of steel have some nuances:

1. Carbon steel. The material is an alloy of carbon and iron. They are easy to sharpen and maintain their sharpness for a long time. People are attracted by the affordable price. Tools made from this material quickly rust in an acidic environment.
2. Low carbon stainless steel. They are a compound of chromium, iron, carbon. Compared to carbon steel, this material dulls quickly due to its low hardness. The main advantage of stainless steel is its resistance to rust formation.
3. Damascus steel. Blades made of this material are multi-layered products that have an unusual pattern on their surface.
4. High carbon stainless steel. High carbon content, plus the addition of molybdenum and vanadium make this material more durable than conventional stainless steel. The products dull slowly and are protected from corrosion.

Ceramic blades belong to a separate group. This material has a high sharpness from the factory, which does not dull over a long period of time. However, ceramic tools are fragile and are not resistant to strong impacts, falls, or the application of breaking force.

Why does the blade become dull?

There are a number of factors that influence the process of dulling a cutting edge:

1. Excessive force transmitted to the tool when cutting. This causes the blade to bend.
2. Incorrect turning process.
3. Cutting hard materials.
4. Improper storage.
5. Impacts against metal objects.
6. Destruction of metal due to corrosion.

Blacksmiths do not recommend washing knives under hot water. This is due to the fact that the metal is affected by aggressive salts, which reduce the sharpness.

How to determine the sharpening angle?

To restore the sharpness of the blade, you need to know the sharpening angle of the knife. To do this, you can use hand tools and inquire about factory sharpening. Knife sharpening tables with standard indicators can be found on the Internet. There are two simple methods for determining the sharpening angle of knives without tables:

1. Using scissors. To do this, the scissors are opened and the blade is placed between the open parts. The sides of the knife should be set at the same distance from the blades of the scissors. Readings are taken using a protractor.
2. Using an angular ruler. This is a special device. Modern models are connected to computers that read accurate readings.

Masters use precision measuring instruments to read indicators. There are also special tables that help determine the angle when sharpening knives.

What sharpening angle is suitable for kitchen tools?

Tools used for cutting food are considered universal. The sharpening angle of a kitchen knife starts from 20 to 30 degrees. Thanks to this, they can cut products of different hardness equally efficiently. The exception is fillet cutting tools. Their sharpening angles range from 15 to 20 degrees.

Hunting

Tools used for hunting are subject to increased stress. Because of this, they are made from more durable materials. The angle for sharpening knives used by hunters is from 25 to 40 degrees.

Proper sharpening of a hunting knife

Sharpening methods

Over time, knifemakers have brought the sharpening procedure to a special technological process, during which a variety of devices and techniques can be used. Knives can be sharpened both with hand tools and on industrial machines.

On the grinding wheel

Sharpening knives using a sharpening wheel is not recommended. This is due to the fact that few craftsmen can limit the cutting edge from overheating. Because of this, tempering of the steel may occur, after which the hardness of the material will decrease. You can sharpen a knife on a sharpening wheel only for large chips or serious damage that would take too long to correct manually.

On abrasive stones

Sharpening a knife is possible using abrasive stones. This is a classic method used by both professionals and amateurs. The grain size of the stones varies. Grains can be large, medium, small. With the help of abrasive stones, craftsmen remove any sharpening of the blades.

Sharpening devices

Sharpening a knife can be carried out using special mechanisms that facilitate this process. Mechanical sharpeners require human effort during the procedure. Expensive devices include automatic machines. With their help you can sharpen blades made of different steels.

Sandpaper or cloth

To correct small burrs and restore sharpness after working with a tool, you can use fine-grain sandpaper or a hard cloth. They are suitable for finishing sharpening knives and bringing the cutting edge to working condition.

Sharpening a knife with sandpaper

What to sharpen with?

Before you start restoring the sharpness of an edge, you need to familiarize yourself with all types of tools for work and their features. Not every device can sharpen a blade to working condition.

Sharpening stone

Sharpening stones, made from abrasive materials, are the most popular tools used for restoring cutting edges. Foreign companies indicate on the surface of the bars the number of abrasive grains per 1 square millimeter. There are stones with small, medium, and large grains on sale. With their help, you can perform both rough and finishing metal processing. Sharpening knives on sandpaper must be done carefully, making movements only in one direction.

Mechanical sharpener

Popular sharpeners that are purchased for sharpening kitchen knives. It is a structure that has two abrasive plates that are fixed at equal angles. It is enough to run the blade over them several times to restore sharpness. Cannot be used for sharpening special blades (hunting, sporting).

Electric sharpener

Expensive devices that are used for sharpening various blades. Allows you to achieve better results compared to mechanical sharpeners. This is due to the fact that this mechanism automatically selects the optimal sharpening angle.

Musat

A cylindrical file, sold separately, included with kitchen tools. Used to bring the cutting edge back to working condition after a short period of use with the blade. If there is serious damage to it, musat will not help.

Lansky sharpener

A special device that is used to restore sharpness to small blades. The main advantage of this sharpener is the ability to set any angles and maintain them throughout the working process. The sharpener is equipped with several bars for rough and finishing processing. The work is carried out manually.

Sharpening and grinding machines

In production, blades are often sharpened on machines. Using industrial equipment, you can accurately sharpen any tool. However, a master must operate the machines. This is due to the fact that the abrasive disc at high speeds can damage the cutting edge if moved incorrectly. We must not forget about cooling the metal during work.

How to sharpen at home?

Sharpening knives with your own hands requires a special approach. To do this, you need to select a device for the work, taking into account the material from which the blade is made. If there are no sharpening tools, you can restore the sharpness of the knife on the knife. To do this, you need to run a dull blade along the butt of another blade several times, performing planing movements. However, more serious sharpening can only be done with the help of special tools.

Another option for turning tools without abrasives is to use glass objects. Jars, bottles, glasses, and glass plates are suitable for this. Simply running the edge over the fragile material a few times will restore its sharpness.

How to sharpen kitchen knives correctly?

You can use different tools to sharpen kitchen knives. The most common ones include grinding stones, sharpening stones, and mechanical sharpeners. We will talk about how to sharpen a blade with an abrasive stone below.

To sharpen a kitchen knife using a mechanical sharpener, you need to place it on a hole with abrasive plates and pull it toward you several times. Musat brings the blade to working condition.

To do this, several movements are performed in one direction on each side of the blade.

How to sharpen on a sharpening machine?

To restore the sharpness of a tool using industrial equipment, you need to follow the sharpening rules:

1. Use a disc with large grains to correct rough irregularities, chips, and large burrs. Finish the edge on the grinding wheel with small grains. If the blade is thin, you cannot use the disc for rough cutting.
2. Sufficient rotation speed of the abrasive disc is up to 150 rpm.
3. We must not forget about setting the exact angle for different types of blades. The parameters are indicated in special tables. Additional devices are used to maintain the angle.
4. When processing, perform smooth movements so that the abrasive catches the metal along the entire length of the blade.
5. Cool the steel during work. The master needs to water the metal with special oil or water.
6. When working with the machine, use safety glasses to prevent metal filings from getting into your eyes.

Any sudden movement may damage the instrument. Even after proper work, the severity can quickly worsen. To prevent this from happening, you need to use the blade only for its intended purpose. Store in wooden stands, do not leave in water for a long time.

How to sharpen with a whetstone by hand?

Sharpening knives at home using an abrasive stone is a process performed in a certain sequence. You need to prepare water and abrasive stones in advance. Procedure:

1. Place a stone with large grains on the table in front of you. It must be fixed motionless.
2. Pour water over the block.
3. Set the required angle between the metal and abrasive surface. To do this, you can use a leaf folded at the required angle.
4. Perform movements along the block away from you so that the entire length of the edge is processed. The knife can only be moved in one direction.

After processing on a coarse-grained stone, change it to a block with small particles and repeat the procedure. During processing, wash off any metal shavings that appear with water. To make the instrument shine beautifully, its surface can be treated with GOI paste.

Proper sharpening of a knife with a whetstone

Methods for checking the blade tip

After carrying out the work, you need to check how sharp the blade is. Several methods are used for this.

On paper

Try to cut a sheet of paper while holding it with one hand. If you can do it without problems, the sharpening is good. A sharp blade will cut the sheet under its own weight.

On a tomato

Often the sharpness of kitchen blades is tested on tomatoes. If it is blunt, the vegetable will be crushed. You need to put it on the table in front of you, try to cut the tomato with the blade horizontally without holding it with your hand. A sharp blade will easily cut a vegetable.

Checking knife sharpening on tomatoes

Testing on hand hair

One of the testing methods that people often use after turning tools. To do this, the knife is pressed effortlessly against the skin of the hand. It should be easily passed through the hair. If the hairs are cut, the blade is sharp, suitable for various types of work.

Everyone uses knives.
However, these tools become dull over time, making it impossible to work with them. To restore the sharpness of steel, you can use different devices. Taking into account the angles for different types of knives, you can carry out the work yourself. Sharpening a knife - the basics, concise, complete, accessible. The simplest correct algorithm for sharpening knives

Source: https://metalloy.ru/obrabotka/zatochka/nozhej

Apex sharpener

For the correct functionality of the blade, its high-quality sharpening is necessary. You need to consider the purpose of the knife. The cutting edge must have the same sharpening angle. It is almost impossible to maintain it manually, with the exception of professional sharpeners. For those new to sharpening, the Apex knife sharpener will come in handy.

History of Apex sharpeners

A dull blade that tears or crushes food and materials will infuriate anyone. Ben Dale initially did not plan to open any companies; he was sharpening knives at a professional level. The line of those thirsty for a sharp blade became unrealistically large.

Ben Dale at the machine at work.

He had to think about simplifying and speeding up the work. With a flair for design, Ben created the first prototype of the Apex knife sharpening machine. It didn't have a brand name at the time, but the operating principle remains the same today.

The first development dates back to the 80s of the last century. About one hundred prototypes of the design improvement were made.

Some competitors also decide to maintain the correct sharpening angle. The movement of the abrasive and, if necessary, the item being sharpened is achieved using an Apex knife.

Having released the invented sharpener, it quickly began to be counterfeited. But this does not prevent the patented brand from Edge Pro Inc from creating extremely reliable and practical products.

Types of Apex sharpeners

Apex Pro and Apex devices for sharpening knives; their strength is the materials from which they are made.

The owner of the brand cares about the quality of components supplied to the plant.

To make the sharpener, a stand from PANAVISE Produkts, Inc is used - a world-famous company specializing in equipping holding devices. Manufacturers of abrasive stones for the Apex Edge Pro sharpener are well-known companies.

Professional knife sharpener Apex Edge Pro System

The weighty base is equipped with vacuum suction cups for connection to the table. The surface must be smooth and even. There is a device for adjusting the stand in height and angle of inclination. A movable element is attached to the vertical guide of the Apex sharpener.

Professional Apex model.

It comes with an abrasive. Its mobility allows you to make movements to the right and left, forward and backward when sharpening. The guide has multi-colored marks, the color scheme indicates different angles. Abrasives can be changed with one movement of the hand. Color matching to sharpening angles:

Label color	Degree
Black	12
Red	15
Black	17
Blue	19
Black	22
Green	24
Black	26

The kit includes a special device for sharpening scissors. In the manufacture of the Apex Edge Pro knife sharpener, the following materials are used: polymer materials, aluminum, non-ferrous and stainless steel. The technical specifications look like this:

• table width – 7.5 cm;
• guide length – 54 cm;
• from the edge of the table to the attachment point – 23.5 cm;
• maximum blade width – 13 cm;
• angle range – from 6 to 33 degrees.

Apex Edge Pro signed by Ben.

The professional version of the sharpener is made individually and by hand. Ben personally signs each one and writes the customer's name. They are equipped with special carrying cases.

Amateur version of Apex

The budget version of the Apex knife sharpening machine is made mainly of plastic, but of decent quality. There are simple suction cups, unlike the Apex Edge Pro with a vacuum mechanism. The simple design is quite reliable and does not cause any complaints. The guide has multi-colored marks corresponding to the corners:

Label color	Degree
Black	10
Red	16
Green	20
Yellow	22

Apex amateur model.

The abrasive elements are also easy to change. Technical characteristics have slight differences from the previous version:

• table width – 6.5 cm;
• guide length – 42 cm;
• from the edge of the table to the attachment point – 17.5 cm;
• maximum blade width – 9 cm;
• angle range – from 9 to 40 degrees.

The device for sharpening Apex knives is equipped with an ordinary fabric bag. The operating principle of both tools is no different. Externally simple devices assembled from several main parts allow you to achieve excellent results.

Advantages and disadvantages of both systems

Nothing is perfect in this world. No wonder Ben Dale spent a decade and tested hundreds of thousands of blades to achieve the best sharpener design. But even today he does not stop at minor improvements. Feedback from real users of the product allows us to highlight the pros and cons:

Advantages	Flaws
Knife length is virtually unlimited	Dirty job
Wide range of corner options	Difficult to handle small blades
Easy to return to factory angles and smooth adjustment	Get used to working with your left hand
There are no restrictions on abrasives, you can also install sandpaper	The blade and handle must be protected additionally
Additional equipment (EP PRO versions)	Considerable dimensions (especially the EP PRO version)

Positive aspects clearly prevail in their favor.

The disadvantages of dirty work are difficult to answer unequivocally. When sharpening knives using water, using any method, there will be dirt from abrasive and metal dust. Controversial minus. Learn to work with your left hand - a left-handed person will be glad of this disadvantage.

The company officially produces three versions of professional versions of machines and also amateur ones. Knife sharpener Apex Pro 3 or Apex 2 should not confuse the buyer, these are slightly structurally modified versions, but the principle of operation remains unchanged.

Tips for use and possible independent improvements

The ideality of things has already been said. Working on Apex Pro and Apex devices implies the inevitable appearance of dirt, and some nuances associated with the friction of stones on metal:

1. One really important point is the wear of abrasive stones. The place that comes into contact with the cutting edge will gradually wear out when sharpening. Reasonably, the angle will change. It is necessary to monitor the condition of the stone, and in order to avoid negative consequences, it must be leveled on special boards.

2. The thickness of the stone also plays a role when setting the angle. Due to this, the colored marks on the vertical guide may not correspond to the declared values. For the greatest accuracy, it is easier to get an electronic inclinometer.

   Thanks to such a simple purchase, the buyer is able to use stones from various manufacturers. And if necessary, the user can actually cut out the stone himself, or use sandpaper and glue it. This is not prohibited in Apex sharpeners. An inclinometer is an inexpensive pleasure, and it can also come in handy around the house.

3. During sharpening, abrasives leave a lot of wet dirt behind during operation, and there is a chance of scratching the blade. To avoid such troubles, cover the blade with masking tape, leaving 5 mm to the cutting edge. Wrap the knife handle with cling film.
4. Preparatory activities before sharpening look simple. It is necessary to soak the stones for 15-20 minutes in warm water. To work with polishing films, you should add a couple of drops of dishwashing detergent to the water.

When sharpening at small angles, a small play appears in the joint of the Apex sharpener on the guide after a while. You shouldn't be afraid of it - it doesn't play a role in the quality of sharpening.

When moving to the band after the stone, make a couple of movements towards yourself. The burr will go down and will not dig into the fine abrasive.

Complete set of EP Pro and APEX abrasives

The design feature of Apex and Apex Pro for easy fastening of abrasives lies in the spring mechanism located on the movable handle. By pulling the round lever towards you, the stone is released from the clamp and can be changed freely. A regular supplier of stones with various grains is the company BORIDE Engineered Abrasives.

A distinctive feature of their abrasives is the aluminum plate attached to the stone. Grit markings are indicated on both sides of the product. The plate allows you to conveniently position the stone in the grooves of the sharpener. It is noteworthy that previously the information was only on the abrasive side; after using the stone many times, it was erased, and the consumer could get entangled in the stones. The omission has been corrected.

Comparative tables of stones from different manufacturers can mislead even an experienced craftsman. The most adequate one can be called just from the company “BORIDE”. In words, the examples look like this:

• extra-hard stone of 120 grit with silicon powder, used for sharpening the hardest blades, hardness up to 63 HRC. The manufacturer has a dark green hue;
• white stone with an admixture of aluminum oxide in 220 grit - medium hardness, used for the most used steels in knives;
• brown colors in 320, 600 and 1000 grit, according to users, are heterogeneous in structure. The new product shows its softness, but over time it becomes more aggressive and less greasy.

Every self-respecting company that produces sharpening stones tries to take advantage of the chance to produce products for Apex. Along with the regular manufacturer, Chosera and Shapton are also striving to occupy their niche. Apex sets for sharpening knives are equipped with sanding belts of 9, 3, 1 and 0.9 microns.

FEPA Compliance Chart.

Surprisingly, the domestic manufacturer VenevAlmaz has also made its mark in this field. Japanese companies have become very active: Ozuki Asagi, Ohira Tomae, Aoto, Shobu, Amakusa, and others. The increasing popularity of the Apex sharpener gives companies the potential to make money on abrasive products.

Analogues from various manufacturers

The EP's design has proven to be quite good and can be customized to suit your tastes. Everyone knows that it is well made and works – it haunts the Chinese. It is imperative to copy and turn the product into a cheap analogue. The Chinese company "Ruixin" produces Touch Pro Steel sharpening machines, let's compare it with a real Apex for sharpening knives:

1. The table and other parts are made of cheap plastic, I think it was recycled. Over time, it will obviously wear out, burn out and break down.
2. When assembling the unit, it becomes clear that the technological solutions for fastenings and hinges are much simpler. After sharpening several dozen blades, backlashes appear in all joints, which will certainly affect the quality of work.
3. Attachment to the table made of suction cups, weak. They are made from cheap polymers. They quickly loosen and stop sticking to the surface.
4. The guide does not have a lock that prevents it from jumping out of the hinge. Significant flaw.
5. The supplied stones are mounted on a plastic backing. Weak base rigidity negatively affects work. When pressed during sharpening, the weak abraded stone will break. The grit marking does not correspond to the declared values.

Chinese version of the machine.

There are many small flaws that allow us to really draw a conclusion. Obviously, you can modify this constructor with your own hands. Professionals recommend throwing stones straight into the trash and buying original ones. Whether it’s worth the trouble is a personal matter for everyone. If you are not a professional sharpener and don’t see the point in shelling out $200-300 for an original Apex sharpener, decide for yourself.

Separately, I would like to mention domestic manufacturers who produce sharpening sets similar to the Apex machine. Which make structural changes, and do not just lick the product. The Lebezh company makes the Cabinet machine, and the Samara Knives company produces the Geometry machine.

Source: https://VashNozh.ru/zatochka/tochilka-apex

Review of the Ruixin Pro sharpener (3rd generation of Egde Pro clones)

Today we have a review of the Chinese sharpener Ruixin Pro - the third generation of Edge Pro clones. Additionally, at the end you will find several recommendations for modernization. A friend of mine provided the sharpener for review and testing, for which we all thank him.

The previous two generations were more similar in design to the original Edge Pro. But in the cheap version of the clones, all the plastic elements quickly broke, and due to the flimsiness of the structure, the base was not stable enough. The 3rd generation is another “work on the mistakes” and they decided to make it completely metal. Let's see what happened with this.

Packaging and equipment

Ruixin Pro is delivered in a simple box made of gray corrugated cardboard, and even then it was difficult to survive delivery. At least the inscription “Knife sharpener” was corrected (at first it was “shar o ener”).

The sharpener parts are packaged in three bubble bags for better preservation, thanks for that. Separately, in a small bag they put a spacer and a bolt with a hex key.

There are no instructions for the sharpener, but that's probably for the best (what's the use of a piece of paper with jumping hieroglyphs?). There is also no roll-up cover, as there was in previous generations.

The equipment is as follows: a frame with 2 screwed plates, 4 stones, a vertical guide, a collapsible (of 2 elements) horizontal guide, a handle, a spacer, a bolt with 2 washers and a 4mm hex key.

Compared to generations 1-2, packaging and packaging have become much simpler. But, personally, I have no complaints, it’s better that the sharpener itself is better than they push all sorts of rubbish at this price.

bed

The base (or technically speaking, the frame ) is quite powerful, made of a solid metal sheet 2mm thick. This is already a big plus compared to plastic structures of previous generations.

The bed has a complex curved shape. From the profile you can see that the lines are not perfectly straight, but, in theory, this should not play a special role. dimensions : 200x50x60 mm (WxHxD).

There are 2 plates . The top plate serves as a stop against which the butt of the knife rests. Front - for fixation, but more on that later. By the way, the name and patent number are laser engraved on it - everything is serious.

From below the frame looks like this:

The counter parts of the wings are peculiar square nuts with a small protrusion that fits into the slot of the frame. Thanks to this, you can tighten the wings without holding the nut. In addition, the soles have 4 holes (~5mm) for screwing to anything.

This is not stainless steel, as some people are pushing, but ordinary steel, but nickel-plated (on a layer of copper). This is clearly visible on the scratches. The plates are similar to stainless steel, all other elements are various alloys.

I won’t particularly comment on the jambs, let everyone decide for themselves based on the previous photos. I will only add a photo of the sole and the thread for the guide. Nothing that a file can't handle, but I wouldn't put the sharpener on a bare table.

Stones

The set includes 4 stones: 120, 320, 600, 1500 grit. Of course, the jump between 600 and 1500 is too sharp, but for home and amateur use this should be enough.

Dimensions of the stones themselves: width - 19-20.5mm, length - 148-151mm, thickness - ~4.2-5.5mm, and the sizes can differ even within 1 stone, and even more so between different ones. The dimensions are close to the original Edge Pro stones (152 x 25 mm or 6 x 1 inch), so you can safely use them if one deems it appropriate.

Stones are glued onto plastic forms . The length of the form is 158mm, thickness 4mm. They are made of fairly durable plastic (even reinforced in appearance) and, together with the stones, they do not have any noticeable flexibility, but still they are not a sheet of aluminum, like the Edge Pro.

From the long edge you can clearly see their entire curvature . The 600th stone on the right is generally poorly glued, but in this case the right edge is much thinner than the left, and the crooked gluing levels the working surface.

From the short edge the picture is even worse. I won’t even comment, everything is already clear.

When magnified , the 120 grit stone looks best. 320 – tolerable, although it has slight inhomogeneities and inclusions. But the 600 and 1500 really let us down - radial marks from the cut ! These are finishing and finishing stones that themselves need finishing, otherwise they will negate all your work.

Obviously, the stones are not the same, with a curved and clumsy surface. But the Edge Pro also has the same problems, despite the fact that one stone costs almost as much as this entire sharpener.

finishing before the first use and during wear (the main method is grinding on glass with silicon carbide powder).

Guides

The sharpener has vertical and horizontal guides (both 7mm in diameter). People call them differently, but for some reason “guides” are closer to me.

The vertical one is screwed into the frame and secured with a wing (as a lock nut). It has a hinge unit, by moving it up and down the sharpening angle is adjusted. There are no marks on the guide in this version of the sharpeners.

The hinge assembly consists of two elements connected by a bolt with a locking nut (the kind with a plastic insert). All the backlashes arise exactly here: between the elements (the gap can be seen in the photo) and in the holes for the guides.

to the horizontal guide and sharpening is done using it. It is collapsible: 2 parts and a handle.

The piece of tube in the new version was replaced with a spring , thanks to which the stones can now be changed by slightly pulling the lock by the finger tabs. And the round handle was replaced with a long handle . When assembled it looks like this:

Is this handle good or bad? It’s hard to say, for me, the round one gives more control over the process and less temptation to press harder. But with the current one, the chance of running into a knife with your hand while sharpening is zero.

The guides are not particularly smooth and clearly need polishing (otherwise it will bore the hole in the hinge assembly, increasing the backlash).

Probably many people are interested in whether it is possible to use diamond bars from DMT . By themselves, of course, they are not suitable. But they can be glued onto forms of a suitable size, or grooves for clamps can be cut into them (otherwise they do not hold well), and a piece of tube can be added to the spring for clamping.

Sharpening process on Ruixin Pro

This version is supposed to clamp the knife for sharpening. To do this, remove the front plate and install it together with the spacer as follows:

The bolt is so that at a small sharpening angle the stone does not sharpen the lamb. But at standard sharpening angles (>20°), a lamb can also be used. The spacer has two sides: 2 and 3 mm - for different blade thicknesses.

The fixing process is not that complicated, but it is tedious: while you are putting the spacer on, the knife falls out, while you hold the knife and tighten the screw, the spacer comes out. And the knife needs to be turned over often (otherwise you can get a huge burr). I understand that with Lansky and the like, the knife is clamped tightly, but there the bars can be easily rearranged from one side to the other and back. But there is also a plus - this fixation solves the problem with the left-right hand.

Another problem is the round outer corner . For wide knives this is not a problem - most of them lie on a flat surface, but with narrow knives there will be difficulties. Perhaps that’s why they came up with the idea of ​​clamping the knife with a plate.

sharpen with light, smooth movements away from you (it will turn out “to the grain”), while simultaneously moving the stone along the cutting edge. This method allows you to avoid (or reduce) the formation of a burr. There is no need to press, and try not to linger in one place.

To set the angle, you can use the table from the Chinese: the first column is the height of the node from the base of the vertical guide (from the plane into which it is screwed), the second is the angle. But this is very approximate , the actual angle depends on the width of the blade and other factors. You can measure more accurately with a protractor, AngleCube and its analogues, or any modern smartphone (by installing a program for measuring angles).

In addition to knives, you can sharpen a lot of other things on the Ruixin Pro: chisels, plane knives, axes, scissors, in general, whatever your imagination allows you to do.

When sharpening scissors, you either need to disassemble them, or place the sharpener on a high base (on the edge of the table) so that the second handle has somewhere to hang. In the photo above, the sharpener is on the handle.

Improvement of Ruixin Pro

Finally, the most obvious possibilities for upgrading this sharpener. Consider this as information for your information; whether to upgrade it and how to do it is up to you.

1. Base . A sharpener on a bare table will move around and scratch it, which means, at a minimum, you need to put something under it or stick it on the “legs” (there are many options: a piece of rubber sheet, double-sided tape, a couple of strips from a Velcro mat, silicone sealant on the base, etc. .etc. etc.).

In addition, the frame can be screwed on. I categorically do not recommend doing this to the table, even if you don’t mind it at all (much less flexibility of use). It is better to take a piece of board, chipboard, plywood, timber, etc. as a base. If you are going to sharpen scissors or other tools, then make the base as narrow - so that the handle has room to hang down.

2. Replace the wing with a nut . The lamb slightly reduces the stroke, and when it hits the hinge unit, it can shift the position of the stone.

3. Polish the rod . You need to be especially diligent - if the diameter changes, it will add backlash. For polishing, fine sandpaper (2000 grit, for example) or GOI paste is suitable. After that, a little lubricant to taste.

4. Eliminate play in the hinge assembly. If you have the opportunity and skills to make something better, then you can replace it altogether, but you can limit yourself to modifications. It is necessary to tighten the bolt of the horizontal hinge assembly as much as possible (so that it can move easily) and add a little lubricant to the contact point. The bumpiness of the assembly on the vertical rod can be eliminated with a plastic washer.

5. Install a good flat magnet . This will allow you to securely and, most importantly, quickly fix the blade on the frame and solve the problem with narrow blades.

6. To prevent the guide from flying out during operation, you can install a limiter . You can cut a little thread and use the same lamb, you can simply put on a piece of rubber tube of a suitable diameter.

number to the back of the stone blanks . The markings are only on the working side of the stones and obviously wear off quickly, and color identification is not always reliable.

conclusions

Pros:

• Durable all metal construction
• The frame is nickel-plated, the remaining elements are coated or made of non-corrosion alloys
• Quick change of stones
• Possibility of sharpening scissors and other tools
• Holes for mounting the frame
• Affordable price

Minuses:

• Rigid fixation of the knife is not particularly convenient and violates the very principle of Edge Pro
• Average workmanship
• Requires modification to work properly
• The stones are frankly crooked, the surface of thin abrasives is uneven
• Low repeatability even within one sharpening
• Bar stroke at best is ~80%
• Due to the rounded edge, it may be difficult to hold narrow blades accurately
• Completely “Spartan” equipment, not even instructions

Quite conflicting thoughts about this sharpener. A kind of hybrid of Edge Pro and Lansky. The durable metal construction is, of course, pleasing, but the rigid fixation of the knife is not. There are other shortcomings, but most of them can be eliminated. The result is another version of the “do it yourself” designer, but vandal-proof. If you know how to work with a file (figuratively speaking), you can take it - for your $23-25 ​​with international delivery it’s quite good.

Source: https://www.toolgir.ru/obzor-tochilki-ruixin-pro-3-pokolenie-klonov-egde-pro/

How to sharpen a hunting knife correctly and at what angle?

Every novice hunter knows that choosing a special knife for hunting is far from easy. In this case, what is meant is not so much the popularity of the model, the cost of the tool, the uniqueness of the shape, or the time of existence of the manufacturing company in the domestic or world market. The choice of a knife for hunting is primarily based on the stated technical characteristics of the product, the materials chosen for manufacturing and the individual preferences of the future owner.

Possible defects on knives

Improper use of the knife can cause the following damage:

• notches and microcracks appear on the edge of the knife;
• the tip of the knife may bend or break off;
• The knife handle and shank may break off.

A real hunting knife is a very expensive item, and for many, knives become a source of pride. In order for a knife to last for many years, as it loses its ability to cut, it needs to be sharpened. There is no need to test the strength of the tool and try to cut the carcass with a dull knife, as this may deteriorate it even more.

Hunting knife maintenance and optimal sharpening angle

In the manufacture of all hunting knives, only hard grades of steel are used, so sharpening them correctly is quite difficult.

And I would like to note that the modern alloys used for making knives are quite flexible, which allows the blade to maintain the sharpness of the cutting edge for quite a long period of time, especially when the tool is handled correctly.

A knowledgeable hunter will never leave his knife sticking in the ground, will not put it in boiling water when cooking, will not open canned food with it, or leave the blade uncleaned after cutting up the prey.

Usually, sharpening a hunting knife is enough to sand and debone one or two large carcasses, but over time the blade loses its sharpness and the tool loses the accuracy and quality of the cut. And in this case, the correct sharpening is of great importance; it is important not to spoil the cutting edge and slopes, to maintain the sharpening angle of the hunting knife, preventing the metal from chipping from the sharp strip of the tool.

It is impossible to properly sharpen a hunting knife without studying the design of the blade. The blade must have bevels on both sides (they are also called chamfers). These chamfers represent a decreasing plane extending from the butt to the blade, as well as a sharp edge of the cutting part, which is sharpened.

The angle of the narrow and even cutting edge determines how sharp the blade is. This sharpening angle for hunting knives should be in the range of 15-30°, and the accuracy and quality of the cut of this tool depends on how accurately it is observed in the process of sharpening the blade. Thus, the first thing to do when sharpening hunting knives is to determine the angle of the cutting edge.

Hunting knives have a certain classification of products in accordance with the existing cutting edge angle, which determines the specification for processing the prey. Hunting knives sharpened at an angle of 30° are suitable for rough chopping and boning work, at 20° - universal knives designed for work of varying complexity, at 15° - for neat thin cuts when sanding prey, as well as separating cartilage and bones.

The angle of the cutting edge is common to both sides. Thus, in order to understand how to sharpen a hunting knife, it is necessary to divide its size in half. The result will decide the question of what the correct sharpening angle for a hunting knife should be, as well as how exactly to position the sharpening device over the tool or place the knife above the abrasive surface.

How to sharpen a hunting knife correctly?

You can use a variety of tools to sharpen hunting knives. So, usually knife manufacturing companies offer to purchase an additional special sharpener when purchasing.

Often, special sheaths for hunting knives have convenient compartments for storing such sharpening devices. In field conditions, mechanical pocket sharpeners are the best choice.

They come in a variety of sizes and shapes, but are always made from only the best materials so that you can restore the sharpness of your instrument with just a few simple movements.

If we talk about the shape of sharpeners from manufacturing companies, they can have the shape of round, light rods, up to 15 centimeters long and several centimeters in diameter.

Such devices are housed in protective plastic cases and also have fastening elements that allow the sharpeners to be placed on a hunter’s belt or in a sheath. Tools of the same type can also have the form of plates.

The material for the manufacture of cylindrical devices is ceramics, flat ones are made of diamond abrasive.

Pocket sharpeners from the manufacturer can also be a small tool of a round, rectangular or oval (with smoothed corners) shape that fits in the palm of your hand. In them, miniature plates of carbide or ceramic stones are located at an angle specified for sharpening in special recesses made in a plastic case.

The greatest effect can be achieved if you take advantage of manufacturers' offers and buy a knife sharpener case. It will help sharpen a hunting knife on a clamp with numbered sharpening angles, using whetstones of different colors, each of which indicates the size of the abrasive grains.

The additionally supplied special oil allows you to achieve perfect sharpening sharpness. This set of sharpeners is not pocket-sized. It is perfect for teaching beginners, and you can start using sharpeners by sharpening, for example, kitchen knives, and gradually master sharpening any cutting tools.

It should be noted that pocket sharpeners are the best choice directly for hunting, but thorough preparation of the tool for it should be done at home.

How to sharpen a knife at home?

The most affordable and fairly effective way is to sharpen a knife at home using abrasive stones. Such bars are presented in a wide range in almost any hardware store, however, in the case of a hunting knife, options with a wide and perfectly flat surface, up to 25 centimeters long and a dense fine- and medium-grained structure can be used.

Sharpening a cutting edge with your own hands must be done in the following way:

• a device with medium-sized abrasive grains is placed and preferably secured on a completely flat surface;
• on a block moistened with any vegetable oil, a knife blade is placed at the calculated desired angle and held with both hands;
• under pressure, the blade is pulled across the surface with intersecting movements, several times towards itself on one side, then the same on the other;
• the process is repeated until a new smooth shiny strip with the same width on both sides is obtained in place of the cutting edge;
• it is necessary to replace the timber with its fine-grained analogue; it is used to fine-tune the sharpness of the blade using several sliding movements without pressure;
• to achieve the ideal condition of the cutting edge, the blade is edited on the back side of the belt, ten times on each side;
• checking the quality of sharpening involves lightly cutting a vertically placed newspaper sheet in one motion.

Expensive tools are best sharpened using special equipment. Specialized service centers and workshops can help with this.

Source: https://ohota360.ru/zatochka-okhotnichego-nozha.html

How to correctly set the cutting edge angle when sharpening a blade

To correctly understand the following material, you need to decide on terminology, which is not always correctly presented on the Internet.

Blade anatomy

Of course, different blades have different cross-sectional shapes, but their common details can still be identified and clearly defined. Therefore, let’s take an average image, using which we can understand all the necessary terms.

Bold italics indicate details that can be found in the figure.

• The thickness of the blade is the thickness usually measured closer to the butt , where the descents .
• The thickness of the reduction is the distance between the points where the descents end and the approaches (one point on each side, see figure). Why the thickness of the information? Because it is there that the metal begins to converge into one line - the cutting edge.
• Leads are narrow planes that, when converging at one point, form a cutting edge. When examining the blade, it is they that shine in the light, and not the edge, as is mistakenly believed.
• The cutting edge is practically an “imaginary” line, which is still several microns thick, but is conditionally only a place where the leads meet.
• Sharpening angle - the angle at which the leads intersect (or descents - in the absence of leads); This term is popularly understood as the “sharpness” of sharpening. By the way, this angle is always greater than the one at which the slopes meet.

Anatomy of a blade: a clear understanding of what descents, approaches and cutting edges are

The smaller the angle between the slopes (and this value ranges from 8 to 50 degrees), the sharper the knife, that is, we have to apply less force to cut.

How to correctly set the overall cutting edge angle

This is important: if we are talking about a knife with symmetrical slopes, then the sharpening angle will be twice as large as the one under which we place the sharpening stone. For example, if we prefer to sharpen our hunting knife at 30 degrees, then there should be an angle of 15 degrees between the blade and the block.

From this we derive two concepts:

• full angle, which is the sharpening angle (in our example - 30 degrees);
• half angle is the one at which we place the blade in relation to the block (in our example - 15 degrees).

We determine the angle itself based on the purpose of the knife.

Special, particularly delicate cutting tools

By these we mean surgical instruments, shaving devices, blades, etc.

The sharpening angle for delicate instruments is 8–10 degrees.

The expression “razor sharp” arose for a reason - the angle of approach of the razor is one of the sharpest among all cutting tools

Knives for working on soft materials

These are mostly kitchen knives: fillet knives, vegetable chopping knives, etc.

The sharpening angle for fillet and vegetable knives is 10–20 degrees.

Universal kitchen knives

Chef's knives for various purposes can work on both soft and hard materials - cartilage, small bones, frozen fish or meat.

The sharpening angle of kitchen “universal” is 20–25 degrees.

Knives for hunters, fishermen, survivalists. Tactical knives

Such tools are often found not only with soft camping products such as sandwiches, but are also designed to cut branches and fishing lines. Sometimes they are even used as sling cutters.

The sharpening angle of “street” knives is 22–25 degrees.

Hunting, tactical (pictured) and survivalist knives encounter hard materials and require a larger approach angle

Knives and other tools for working on hard materials

This includes kukris, machetes, garden knives, tourist and ordinary household axes.

The sharpening angle of knives for heavy work is 20–40 degrees, sometimes up to 50.

How to understand what kind of sharpening a tool requires

Sharpening does not always follow a single algorithm. For example, if we use an expensive and high-quality knife for its intended purpose and regularly care for it, most likely it only needs editing. But an old tool that has not been touched by a sharpening stone for a long time may require not only sharpening, but first of all repair.

The task of both editing and sharpening is to restore the original state of the cutting edge. What could happen to her? It either becomes blunt (that is, instead of the line on which the leads meet, an additional rounded surface is formed), or damaged (jams and chips appear on the line of intersection of the leads), or it is completely pulled towards one of the leads. The last case is typical for knives with one-sided sharpening.

If the cutting edge is simply slightly deformed and deviates from the specified straight line (without cracks or microscopic chips), it can and should only be corrected without removing a large amount of metal. On hard steels this is done using laps, belts and slings with fine-grained abrasives, on softer steels - with the help of musats, almost smooth dressing devices, since sometimes even abrasive materials are not required.

If the leads are already a little worn, covered with micro-scratches and micro-chips, and the line where they intersect is slightly rounded (usually they say that “the edge/blade/blade is becoming dull,” but this is not entirely correct), sharpening is needed. In this case, the shape of the inlets is restored using diamond bars or water stones.

The blade that is subject to repair is the slopes and leads of which have already lost the geometry necessary for work: deep chips or severe wear have appeared on the blade, and the thickness of the lead has increased by one and a half to two times. Therefore, in order to bring the knife into working condition, you will have to re-form the descents and approaches, which is beyond the power of a person without experience and special tools.

***

How did you learn to draw the angle correctly? Or maybe you haven't had to do this yet? In this case, you can contact us for the service of sharpening knives and other cutting tools: we know how to do this professionally.

On sale

Source: https://www.tojiro.ru/clients/blog/zatochka/kak-pravilno-zadat-ugol-pri-zatochke/

How to sharpen knives correctly

tojiro.spb.ru

This tool is very similar to a file: a long round rod with a notch and a handle. It is mainly used for straightening the cutting edge of a knife. This is useful because it allows you to keep the knife in working condition at all times. But if the blade has become very dull, grinding stone will not help you - a major sharpening is necessary.

Buy

2. Mechanical sharpener

cook-r.ru

Not a bad thing that every housewife should buy. Well suited for sharpening kitchen knives as it is quick and easy. True, the quality is not always pleasing, and the knives become dull as quickly as they are sharpened. This method is suitable for a kitchen knife, but no more.

Buy

3. Electric sharpener

klevin-knife.ru

A great way to quickly and efficiently sharpen knives with any type of blade, as well as scissors and even screwdrivers. The device is capable of sharpening and then polishing any blade in two minutes. It is important that it automatically determines the desired sharpening angle, but we will talk about this below. Such a thing will cost from 2 to 50 thousand rubles, depending on the sharpening speed, guide system and power.

Buy

4. Machine with abrasive wheel

kak-eto-sdelano.livejournal.com

This is a professional tool; it is used to sharpen and polish blades in industrial enterprises. Without experience, it is better not to go to the machine: steel is hardened at a certain temperature, so uncontrolled heating on the machine during sharpening can irreparably damage the knife. Leave this method to the professionals.

5. Whetstone

tojiro.spb.ru

Sharpening with a whetstone is one of the most effective methods. This process is not easy, but entertaining. It requires perseverance and some experience working with a bar. For sharpening, two stones are needed: with small grains and large ones.

There are two types of whetstones: natural and artificial. The whole difference is in the grain size: natural stones are usually fine-grained, they are used for polishing. And artificial ones are initially made more universal, with different degrees of grain on different sides of the bar.

Buy

How to sharpen knives

vottak.net

Before proceeding with the sharpening process, immerse the sharpening stone in oil or water for 15 minutes. This will extend the life of the bar, since steel particles will not get clogged between the grains.

You should start sharpening with a coarse-grained stone. It is important to correctly position the blade relative to the surface of the block, since the final result largely depends on this. The correct sharpening angle is also important: experts advise sharpening the blade at an angle of 20 degrees, but this may vary depending on the type of knife.

• Professional chef's and fillet knives require an angle of 25 degrees.
• Japanese kitchen knives should be sharpened at an angle of 10–20 degrees.
• For hunting blades, an angle of 30 to 45 degrees is used. A larger angle is required for greater resistance to dulling.
• For household kitchen knives, an angle of 30 degrees is sufficient.

The rule here is simple: if you want to make the knife sharper, we reduce the sharpening angle, and for greater resistance to dulling, we increase it.

You need to sharpen with continuous movements, lifting the handle at the moment when the block reaches the bend of the blade. This will maintain the sharpening angle of the cutting edge. It is important that the movement of the blade is perpendicular to the edge, while applying slight pressure to the blade.

Grinding

lastday.club

When the main sharpening has been completed, we begin grinding. For this you will need a fine-grained stone. Grinding is necessary to level the surface and remove burrs. The technology remains unchanged.

Conclusion

In theory, everything is quite clear, but in practice, the process of sharpening a knife is far from the simplest. You will have to be patient and attentive: one awkward move, and all the work will go down the drain. Theory is great, but you can’t do this without practice. And the process itself is not cheap, since good sharpening stones cost a lot of money.

If you just need to sharpen your knives, without all this fetish, take an electric sharpener. The result will be the same, and this method will also save your nerves and time.

Source: https://Lifehacker.ru/kak-pravilno-tochit-nozhi-2/

How to set the knife sharpening angle correctly

The ability to determine the sharpening angle of knives and correctly process the cutting edge (RC) is necessary for safe work with them both at home and on the go. Following recommendations on how to keep your blades in good condition will help extend their useful life.

Why does the knife get dull?

Sharp objects are dangerous because you can get hurt when using them. But even more trouble will come from a dull chef's knife, which can slip and easily injure your hands.

The blades sold in the store are sharp and easy to work with. But their shelf life depends on operating conditions.

Following a number of recommendations will help keep your kitchen knife sharp longer:

• during storage, the cutting edge should not touch surfaces that have a high density;
• cutting should take place on special boards made of wood or plastic;
• blades of all types must be used for their intended purpose, avoiding shock loads on blades whose sharpening has a small degree;
• Immediately after use, knives should be washed and dried.

The sharpness of the cutting edge decreases for several reasons:

1. Impact of organic acids contained in products on the blade material.
2. Impacts from a fall.
3. Cutting on hard surfaces such as stone countertops or ceramic cookware.
4. Uneven load on the cutting blade when the composition of the products is uneven (the blade hits bones, tendons when cutting meat).
5. Exposure to aggressive chemicals and high temperatures during cleaning.
6. Improper use.

If the knife is intended for cutting the fillet of fish, then when opening cans with it, the blade will be damaged. The nature of the RK violations depends on the material from which the blade is made.

Knives made of stainless steel are resistant to aggressive environments, but without proper care, rust appears on the surface of the blade. Such blades are easy to sharpen, but this process must be carried out more often.

Carbon steel has increased strength, such blades are more difficult to sharpen, but they retain their sharpness longer. With insufficient care, the metal quickly becomes covered with rust.

By combining hard and soft steel in industrial production, alloys are created that imitate the blacksmith forging inherent in Damascus blades. Knives are made primarily for hunters using this method.

Products made from zirconium alloy are characterized by increased fragility. These ceramic knives are designed for smooth, soft products and keep their blade sharp for a long time. A special tool is required for sharpening.

Knife device

Any knife consists of a metal or ceramic strip and a handle, which is made of wood, plastic, ceramics or other materials. Depending on the way the handle and blade are articulated, knives can be fixed, folding or detachable. The handle can also be positioned perpendicular to the cutting blade.

The blade has a RC formed by two or one microfeed. Depending on the shape of the perpendicular section, the cutting edge can be formed by a bevel without microfeed.

The part of the blade opposite to the RK is called the butt. It can also have a sharpening, as in the case of a double-edged knife. The section of the blade that is adjacent to the handle and has no sharpening is called the heel.

Shapes and sharpening angles

Depending on the purpose of the knife, there are several blade cross-section shapes:

1. Scandinavian, when the descent connects the butt with the RK and the cross-section has a wedge-shaped shape. A small angle is convenient for cutting, but does not withstand impact loads well.
2. Scandi - the RK angle is more obtuse than in the first case. It withstands shock loads better, but cuts worse.
3. Razor, when the slopes have a concave shape, which provides a small angle for the cutting edge and ensures high cutting quality. This sharpening is used for straight razors. It is not recommended to subject the blade to shock loads.
4. Lenticular - the descents are curved, while the angle of the RK is of greater importance. This cross-section is typical for axes intended for chopping.
5. One-sided - the descent is designed on only one side of the blade. This type is typical for carpentry tools and knives made in Japan.
6. European - a wedge-shaped descent from the end turns into a micro-approach at the edge. This cross-sectional shape of the blade provides an increased angle compared to the Scandinavian cross-sectional shape, due to which the blade better tolerates shock loads, allowing chopping movements.

Table of values ​​for different knives

A table is used to determine the optimal sharpening angle.

How to choose the optimal knife sharpening angle?

Firstly, there are standard recommendations that can and should be followed. They were developed a long time ago and have been tested by more than one generation:

— Fish cutting (filleting). 25°

— Boning knives (cutting meat). 25-30°

— Chef's knives (chef's work). 25-30°

— Kitchen knives (home cutting, slicing). 30-35°

— City knives (folding, penknives). 30-35°

— Vegetable knives (peeling vegetables, slicing). 35°

— Tourist knives (hiking, survival knives). 35-40°

— Hunting knives (cutting large trophies). 40-45°

The rule here is simple and clear. The smaller the sharpening angle, the easier the knife cuts food and other materials, but it will have to be sharpened/sharpened more often. Accordingly, the larger the angle, the longer the knife will retain its cutting qualities, but during the work you will have to put in more effort.

In Zlatoust, gunsmiths adhere to a sharpening angle of 40 degrees. Considering it "universal". Maybe this is the “golden mean”?))

Well, seriously speaking, it is simply impossible to take into account all the needs of clients. Therefore, we sharpen it at 40 degrees. Who needs more or less? Resharpen.

Sharpening angle and other factors

Many factors influence the ability of a cutting tool to maintain its edge. The sharpening angle is just one of them. If due attention is not paid to the heat treatment of steel, then at low values, sharpen the knife at least 50 degrees, it will quickly “sag,” and at high hardening values ​​(overheating), the cutting edge may simply crumble.

There is also the so-called “scandi” sharpening, when the bevels on the knife are made on a belt grinder almost “to zero” with a slight microfeed. Such knives are designed for heavy “batoning”, when you can easily chop even logs with them, striking the butt with another log or a hammer.

The situation may be like this: good steel, hardened according to all the rules, but “sharpened on a grindstone,” that is, on a high-speed abrasive wheel. Such a knife will also not hold an edge for long. Therefore, when purchasing a knife, pay attention to what manufacturer is behind it. Veteran gunsmiths, as a rule, take all these parameters into account when making knives.

Sharpening angle “so that the nail can chop”

Everyone has probably heard the story about how a Damascus/damascus/super steel knife cuts a nail. Reveal a secret? Even an ordinary “Chinese steel” is capable of such a trick. What can we say about damascus or damask steel?

The conditions for such a focus are:

• steel hardness is in the range of 56-61 HRC and .
• . sharpening angle 50-60 degrees.

Cut nails for your health if you need it ((. Don’t believe me? Write below, we will conduct such a test and film everything on video.

How to choose the right sharpening angle?

Experimental! Refer to the table at the beginning of the article and try deviations up or down based on your goals. Carbon steels, by the way, allow the use of a sharper sharpening angle. Therefore, for knives made of Damascus or cast damask steel, it is possible to deviate in a smaller direction (within reasonable limits) without fear of jamming the cutting edge.

For reference

When purchasing blades for making knives yourself from our catalog, you can order the required sharpening angle. We will happily sharpen them to 25, 30, 35, 40 or 45 degrees using Swedish Tormek equipment. And so that there is no misunderstanding: when we talk about the sharpening angle, we are talking about a full angle, not a half angle. The diagram below shows exactly the half angle. Multiplying it by 2, we get the full one.

The article was prepared by the Zlatoust Knives online store.

Source: https://moy-instrument.ru/masteru/kak-pravilno-vystavit-ugol-zatochki-nozha.html

Knife sharpening. Basics

The tool must be in working condition. In the case of a knife, the main characteristic of the working condition will be its sharpness. We will tell you how to sharpen a knife correctly, what tools you will need for this, and give you a number of useful instructions. "Knife sharpening. Basics" is a basic article for those who are just starting to get acquainted with this art.

How does the blade get dull?

We buy a sharp knife at the store, but over time it inevitably becomes dull if, of course, we work with it. Why does this happen, since the tool is made of good steel and sharpened at the factory? The process takes place at several levels:

• Microscopic, when particles of steel are ground off the cutting edge during friction with the material, making the edge less sharp. You can't see it, but you can feel how more and more pressure is required to cut over time.
• Macroscopic, when the tip encounters solid inclusions, such as grains of sand, particles of stone or metal. They are found in almost any material. The edge either moves the obstacle away or moves away itself, while crumpling.
• If the blade is used inappropriately, its blade can be damaged beyond recognition. This means unscrewing screws, digging soil, etc.

As a result, the working part of the blade is deformed, the edge loses its sharpness and the tool becomes less and less suitable for work. Gradually, hardened steels crumble, and softer and more ductile steels begin to curl.

Rice. 1. The process of blunting and sharpening a knife: 1. When working with a knife, the shape of the cutting edge changes randomly. 2. During the sharpening process, we return the specified shape of the cutting edge or change it. 3. And we give it smoothness, finally removing the burr.

To return the knife to working condition, it is necessary to eliminate the resulting deformation and restore the correct shape of the blade.

What are knives sharpened with?

When sharpening a knife we ​​use a similar process - friction, but this time we control it. With uncontrolled deformation of the steel, the knife becomes dull, with controlled deformation it sharpens, that’s the whole difference.

You can sharpen a steel wedge with any abrasive tool, and in the beginning it was fragments of stones and pebbles. We are modern people, so we will use a specially designed sharpening stone.

If you use a cheap stone to sharpen good steel, be prepared that it will quickly wear out and lose its flat shape. Therefore, it is better to immediately purchase a good ceramic sharpening tool or a diamond-coated sample.

Three types of abrasive are enough for the job:

1. Rough - about 350 units/cm² or diamond marked 160/125. Needed to eliminate severe deformation and is rarely used.
2. Fine - about 650 units/cm² or diamond marked 100/800. Needed for normal basic sharpening of a knife that has become dull within reasonable limits.
3. Ultrafine - about 1150 units/cm² or diamond marked 20/14. Useful for grinding and final finishing, removing burrs.

For constant work, bars of the last two types are required, because bringing a knife to a state in which a rough stone is needed is blasphemy. However, an experienced master has all three types.

For convenience, the following points are important:

• The length of the bar should be 1.5 - 2 times longer than the blade.
• The width should be 2.5 – 5 cm.
• The height should be such that your fingers do not touch the table.
• The block should stand firmly and not slide on the table.

For example, to sharpen a knife on small whetstones, you can make a device like this.

The listed points are very important for achieving correct sharpening, especially at the learning stage. Then, when you get the hang of it, you will be able to cope with the task in less comfortable conditions, but at first, convenience plays an important role.

How to sharpen a knife?

We've come to the most important thing. Sharpening a knife involves placing its blade on a whetstone at a certain angle and running the entire cutting edge along it from the heel to the tip. Proper sharpening requires compliance with three conditions:

1. The angle of inclination of the blade plane to the surface of the sharpening stone remains strictly unchanged (Figure 2).
2. The edge line at the point of contact with the block must be perpendicular to the direction of movement (Figure 3).
3. The pressure should be moderate and uniform; there is no need to “iron” the sharpener or remove chips from it.

• Figure 2
• Figure 3

So, we place the blade on the stone perpendicular to its long side, set the angle to 15-20˚, and begin to move the blade along the stone, gradually moving it from the heel to the tip. When turning the edge closer to its end, the handle should be slightly raised above the plane of the stone and pulled back, as if lagging behind the tip. This will allow you to maintain the same angle of inclination and perpendicularity of movement.

When the pass along the entire edge is completed, it is necessary to repeat it in reverse order, as when rewinding. This will make it easier to maintain the correct angle and overall the work will go faster. We perform these movements until a “burr” begins to appear on the opposite side of the edge.

The “burr” can be seen or felt with the skin of a finger when running it perpendicular to the tip. When the edge begins to scratch along its entire length, stop sharpening one side and begin processing the opposite side.

The knife is turned over and work begins on the other side. Gradually, a moment will come when, like last time, a “hangnail” will appear. This means the second side is ready. More precisely, almost ready.

Next, we take a thinner abrasive and start the process from the beginning. Similar to the previous stage, we achieve the appearance of a “burr” first on one side and then on the other side of the cutting edge. At this stage it will be much smaller and thinner.

Finally, the blade is polished to the finest abrasive. Here it is necessary to carefully polish the cutting edges, as if stroking them, and remove even the smallest “burrs.”

Blade position relative to the sharpening stone:

Source: http://knifehacker.ru/zatochka-nozha-osnovy-i-poleznye-sovety/