Military Review

Knife blade design

21
Knife blade design

History Knives began with knives, in which the blade was rigidly attached to the handle and was constantly ready to work. Currently, despite the wide spread of folding knives, such knives have not lost their relevance. They are indispensable in the field (fighting, hunting, tourist), are widely used in urban environments (knives of constant wear and knives of self-defense) and dominate the kitchens in apartments and catering establishments. Abroad for them was fixed the name of the knives with a fixed blade (fixed blade knives) on the knife slang - “fixed”. However, this is not a very good definition, since many modern folding knives have a special mechanism for fixing the blade in the open state. It would be more correct to call them clumsy knives.


Unlike folding knives with a fixed blade have a number of advantages:

they are always ready to work - no need to open a blade that can jam due to contamination of the hinge;
they are reliable in use - there is no risk of spontaneous addition of the blade due to a defect, contamination or destruction of the knife fixing mechanism.

Intermediate position between knives with a folding and non-folding blade is occupied by knives with replaceable blades, which can be non-separable and collapsible.

The basis of non-separable knives with replaceable blades is a steel strip, one side of which is a knife blade, and the second is an instrumental blade (sometimes a blade with a different sharpening or shape). Changing the working blade occurs by throwing the knife handle.

Collapsible knives consist of a handle and a set of blades that can be fixed on it.


Knives with interchangeable blades are superior to classic single-blade ones in terms of functionality, but they are inferior to them in terms of reliability and wearing comfort.

Despite the fact that the design of knives is much easier than folding knives, they have a number of features and elements. As a rule, on the websites of online stores, in catalogs and websites of manufacturers of knives the main characteristics of knives are given:

appointment;
total length of the knife;
length of the blade;
thickness of the butt;
blade hardness;
knife weight;
blade material handle and scabbard.

In foreign sources, the overall dimensions of the knife are usually given in inches (1 inch = 2,54 cm), and weight in ounces (for example, 1 ounce = 28,4 G).

A complete picture of the knife can be obtained from their reviews in specialized journals or knife sites. However, for this you need to have an idea about knife terms, which can be a known difficulty for the average consumer.

A lot of useful information about knives can be obtained on knife forums on the Internet. However, regular participants of these forums, apart from official terms, widely use specific knife jargon, which for the uninitiated may seem abracadabra. Therefore, at the end of the article is a brief dictionary of knife slang.

The purpose of this article is to help people who are not enthusiasts and connoisseurs of knives and the knife industry, but simply want to acquire a reliable, clumsy knife, fully aware of the purpose of its elements and not overpaying money for useless design features (the cost of an awkward knife can vary from hundreds to tens of thousands rubles).


For an ordinary person the most important information about the legality of owning a knife. Ie. Does it apply to cold arms (CW), for the acquisition of which a special permit is required and there are certain mandatory rules for its storage and carrying, or it is a knife for household purposes (colloquially “household goods”), the acquisition, carrying and use of which is not subject to strict legal frameworks.

Only an expert who is guided by a number of signs and test results, the description of which can be found in the special literature, can determine whether a knife belongs to CW.

For the average consumer, it’s enough to have a copy of the certification test leaflet. This document contains not only the main characteristics of the knife and the name of the manufacturer, but most importantly - the conclusion of the examination of its recognition of household. The presence of this document from the owner of the knife will help avoid a number of problems with law enforcement officers.

Whatever the seller or manager may say - the absence of such a document, whether it is a knife shop or a specialized knife shop, testifies either to its incompetence, or to the fact that the acquired knife did not pass certification tests and could well prove CW, causing its future owner a lot of trouble .

It should also be borne in mind that the knife companies can produce different versions of the same model of the knife, outwardly very similar, but belonging to different categories. Therefore, when you receive a leaflet, you must carefully compare the image contained in it with the knife that you hold in your hands. If the image in the information sheet does not match the original - such a document is worthless.


Some Chinese manufacturers produce copies of combat knives by famous western companies in the form of do-it-yourself kits. By itself, this set does not require certification. However, the knife assembled from this set of parts will be a melee weapon with all the ensuing consequences.

Design

The main elements of a knife are a blade, a handle and a stop. The blade is the basis of the knife, it is they who do all the work with the knife. The handle determines the convenience of the knife. The limiter protects the fingers from slipping on the blade of the knife.

These main parts can be made as separate structural elements or they can be formed from one piece of material. Such knives include, for example, the so-called "skeletal" knives, which received their name from the shape of the handle, somewhat reminiscent of the skeleton due to the holes in it of various shapes. The handles of these knives for ease of retention in the hand are often wrapped with a cord.

Blade

The blade of clumsy knives in the classical form represents a strip of steel, one part of which is sharpened (the blade itself), and the second, the shank, serves for attaching the handle to the knife.

The performance of the blade is determined by its material, manufacturing technology, geometric shape and cross section of the blade.

Blade material

In the knife industry, various types of steel have become and remain the most common material for the manufacture of the blade: carbon, alloyed (stainless) and patterned (damask).

There are a lot of steel stamps, and their full description may take more than a dozen pages. A large variety of steels used for the production of knives is associated with the need to obtain mutually exclusive qualities of the blade - ease of sharpening and duration of preservation of cutting properties, resistance to shock loads and hardness of the cutting edge.

Indicator of wear resistance (duration of sharpness of the blade) is the hardness of the blade. It is usually measured in units of Rockwell “C” scale - HRC. The higher the number, the harder the blade of the knife.


The blade acquires hardness during the heat treatment of the blade workpiece (quenching, tempering). With improper heat treatment, even with the most advanced and expensive steel, you can get a low-quality blade, and vice versa, even with simple, inexpensive steel, you can make a blade with good performance.

Usually, knives of knives with knives have an index in the 42 ... 61 HRC range. Hardening blades to values ​​greater than 61 HRC leads to increased brittleness of the blade, and below 42 HRC - to low wear resistance (usually these blades have souvenir copies of cold weapons).

The traditional material for blades is carbon steel (the main components are iron and carbon). Low carbon steels (0,4 ... 0,6% carbon) allow to produce blades, the blade of which can withstand shock loads (viscosity of the blade), easily sharpened, but also easily dull. Blades of high carbon steels (0,7 ... 1,2%) for a long time retain the sharpness of the blade, but harder to sharpen and poorly withstand shock loads. A common disadvantage of carbon steels is their low corrosion resistance, which requires specific maintenance of the blade or the application of a protective coating on it so that it does not become rusty.

A special place among the blades made of high carbon steel (up to 1,2 ... 2,0% carbon) is occupied by blades from damask steel. As a result of trial and error, the masters of antiquity learned how to get steel of complex structure. Such steel allowed to make blades that combine hardness, resistance to mechanical loads (viscosity) and elasticity. The unique properties of bulat are associated with the formation of micro- and macro-inhomogeneities in the metal structure. The presence of these inhomogeneities is due to the specific pattern on the surface of the damask blades, and the larger and clearer this pattern, the higher the quality of damask.


The secret of making Bulat was irretrievably lost. As a result of painstaking studies of samples of old Bulat and many experiments by Russian scientist Pavel Petrovich Amosov in 1830? X. a technological process was developed that allows to produce steel with properties similar to damask steel.

Knives from damask are a piece and expensive goods. This is due to the high laboriousness and complexity of the manufacture of Bulat, resulting in instability of obtaining high-quality Bulat and a high level of marriage (even among the most famous masters, it can be up to a third of products).

The fashion for knives from damask led to the appearance of products on the knife market, which have nothing to do with this bulat. For example, to obtain a damask pattern, stainless steel forging is used, followed by etching or re-melting of alloyed steel using the damask technology. To distinguish in appearance such knives from real damask even to a specialist is not easy.

Nowadays, blades made of stainless steel with high performance characteristics, thanks to their additives (chromium, tungsten, molybdenum, etc.), are the most common. Despite its name, this steel is also subject to corrosion, although to a much lesser extent than carbon. It is caused by the presence of impurities, which are less, the higher the culture of production and, of course, the price of a knife made of such steel.

An attempt to combine the “elasticity” and “hardness” of various steel grades in one blade led to the creation of composite blades. That is, blades consisting of several types of steel.


Damascus steel is produced by repeatedly forging twisted strips of steel with low and high carbon content. As a result, the final product combines high flexibility and blade hardness.

The surface of the damask blades has a pronounced pattern. Modern technologies for obtaining Damascus allow you to pre-design the look of this pattern and get a variety of images on the blade.

However, as in the case of damask, making high-quality Damascus is a complex, lengthy and expensive technological operation. Its high-quality implementation is available only to units of producers. The consequence of this is a high final cost of products and a high level of rejects. At the same time, it is difficult to distinguish a real “worker” damask from a decorative one and assess the quality of its production for a non-expert. Therefore, there is a high risk of acquiring a beautiful knife that looks good on a shelf in an apartment, but is useless for doing real work. Moreover, some manufacturers produce blades that mimic the surface of Damascus steel (drawing on the blade in various ways, drawing "under Damascus").

Another manufacturing technology for composite blades is packaging - the creation of a blade from a welded stack of steel strips, in the center of which there are “hard” steel grades, and on the sides - “soft” plastic. This allows the manufacture of blades that combine high hardness with elasticity.

It should be noted that the current opinion about the alleged "self-sharpening" of such knives is not true.

The complexity and complexity of this technology and, consequently, the high cost of final products has led to its low prevalence. Mostly knives with multi-layered blades are produced by Scandinavian and Japanese manufacturers at a cost of several tens of thousands of rubles.

In the knife market, you can also find clumsy knives with a blade of titanium alloys, ceramics and various types of plastics.

A special feature of knives made of titanium alloys is their very high corrosion resistance, strength that persists to a temperature of minus 50 ° C, elasticity and low weight. The disadvantages of the titanium blade include the low resistance of the cutting edge, the difficulties of its restoration and the high price of knives with such blades (8 – 10 is higher than a similar knife made of steel).


These features led to the use of knives with a titanium blade - fishermen, divers, lovers of boating. Since titanium is a non-magnetic metal, such knives are in service with combat swimmers.

Ceramic blades are not subject to corrosion, have great hardness of the cutting edge and its durability. The lack of such knives is high brittleness. The result of the impact of lateral load or the fall of the knife on the floor will be a breakage of the blade. In addition, to restore the blunted cutting edge in such knives is not possible. Ceramic blades are widespread mainly in kitchen knives.

Recently, technologies for creating composite blades with a core of ceramics and steel plates have been developed. Their completion to industrial use will allow the creation of blades that combine the hardness and wear resistance of ceramic blades with the strength and elasticity of blades made of steel.

Knives of various types of plastics are not intended to be reused. For strength and cutting ability, they are significantly inferior to knives with steel blades. Their main advantage is “invisibility” for metal detectors, which determines the scope of application - concealed carrying knives.

Additional surface treatment of the blade

The surface of the blade is often subjected to additional mechanical processing (polishing or matting) or it can be applied a protective coating in the form of an oxide film, a polymeric material or a thin layer of metals or their compounds. The purpose of such processing is:

make the surface of the blade shiny, glare or, on the contrary - matte and dark (glare-free);
protect the blade from corrosion;
increase its durability.

Polishing (mechanical or electrochemical) is a classic type of treatment, as a result of which the surface of the blade acquires not only a mirror shine, but also additional protection against corrosion.

Matting In some cases, the glare of light on a polished surface is an undesirable factor (combat and tactical knives). In order to make the surface of the blade matte, special methods of machining the surface of the blade are used - satin finishing, rough grinding or blasting.

When satinizing, the blade surface is covered with micro-strokes using special brushes or sanding pads.
Rough grinding (stone-washed) of the blade is made by rolling pebbles.


As a result of satin finishing and coarse grinding, the surface takes on a matte appearance, glare of the blade is weakened, but it continues to reflect direct sunlight.

During blasting, a jet of small particles (sand, corundum chips, glass beads) is sent to the blade under high pressure. In contrast to the two processes mentioned above, in this case some hardening of the blade surface occurs. But when processing corundum particles, the surface of the blade acquires a strong roughness, which worsens the resistance of the blade to corrosion.

Burn-in (oxidation, blackening) - getting a thin oxide film on the blade surface. One of the most simple and cheap coatings that give the blade a dark color. In former times, it was one of the main methods for protecting the carbon steel blades from corrosion (stainless steel blades are not blunt). However, bluing does not tolerate the effects of acids (lemon juice, barbecue marinade and vegetables, etc.). Therefore, it is currently used only in cheap models of knives or for decorative purposes.

Parkerization is the coating of the surface of the blade with phosphate, as a result of which the surface of the blade acquires a matte-gray color and increases its wear resistance. In modern knives, such a coating is rare.

Nickel plating, chrome plating is widely used in the production of awkward knives. It gives the blade the same sinister shine, often described in the literature.

The achievements of modern chemistry and the introduction of new coating technologies have led to the emergence of new protective coatings of blades.

Epoxy coating (powder coating) - application of epoxy resins on the blade of heated powder. Such coatings can be applied to any type of steel and painted in any color. This coating protects well against corrosion, does not glare, but does not differ in high resistance to mechanical stress. Damage to the coating quickly leads to flaking, so basically it has been used in low-cost models of knives.

Teflon and PTFE coatings well protect the blade from the effects of water, alkalis and acids. In addition, they facilitate the cutting of materials as a result of reducing friction on the side surfaces of the blade.

Most often, this coating has a black color. As a result of operation, the surface of the blade rather quickly becomes scratched. Since the protective film is embedded in the top layer of steel to a depth of several microns, these scratches do not lead to the loss of the protective properties of the coating.

Compared with epoxy coatings, such treatment of blades is more expensive.

Coatings from compounds of refractory metals (titanium nitride TiN, titanium carbonitride TiNC, titanium carbide TiC, boron carbide B4 C, chromium nitride CrN, etc.). Coatings have a different color - from golden to dark gray or black.


For the application of these coatings, quite complex technologies are used - plasma spraying and ion-plasma deposition. A thin protective film of these materials (3 – 5 μm) is embedded in the surface layer of the metal at the molecular level and perfectly protects the blade from corrosion, has a high mechanical resistance.

To designate these coatings, manufacturers often use their brand names. For example, titanium carbonitride-based coating used in Benchmade knives is called Black-Ti.

Diamond-like coating - DLC (Diamond-Like Coating) came into the knife industry from mechanical engineering. It is a thin carbon film (0,5 ... 5 μm), the structure of which combines the properties of diamond and graphite. When applied to the metal surface, it significantly increases its strength properties, resistance to aggressive media, reduces the coefficient of friction.

The last two types of coatings provide not only high resistance of the blade to corrosion, but also provide a multiple increase in its wear resistance (hardness of the cutting edge), although this slightly reduces the sharpness of the cutting edge. The DLC coated blade in 5 – 10 retains its cutting properties once more. However, due to the complexity of the technological process of applying these coatings, the cost of a knife rises several times. Such coatings are used in expensive elite knives.

A common disadvantage of all the considered coatings is that on the blade of the blade their protective properties are lost after the first sharpening.

In recent years, it has become fashionable blades with traces of scale or forging, emphasizing the manual manufacture of a knife. However, from a functional point of view, such blade processing has no advantages, and in terms of resistance to corrosion, they significantly lose to blades with a protective coating.

Blade geometry

The shape of the geometry of the blade and its cross section allows you to optimally implement the properties of the material from which the blade is made, to perform the work for which the knife is purchased.

Usually the blade of the knife is flat and its shape does not differ from the shape of the blades of folding knives (for more, see “Folding knife anatomy”, “Brother”, January 2013). However, there are also knives in which the blade strip is twisted into a spiral, as well as knives in which a hollow metal tube is used instead of a flat strip. Such knives are intended only for inflicting stabbing in a knife fight or in self-defense and are not applicable to the normal operations associated with cutting or planing objects.

The tip (toe) of the knife determines its piercing abilities and is formed by beveling the bezel and raising the blade. Contrary to the name, the knife edge may not be sharp. The rounded edge, for example, has knives for rescue operations.


Classic knives have only one edge, although models with two points can be found on the market. It can be double-blade knives, the shape of which is inspired by the shape of the sacred Muslim sword zulfikar. It is believed that in the slot between the blades can catch the blade of the enemy, although it is quite doubtful. More interesting are knives for personal self-defense, having two points, but without a gap between the blades. In such knives, the small length of the blade is compensated by the possibility of the so-called “frontal cut”, in which not a piercing occurs, but a cutting of the target during a piercing blow.

As a rule, the thickness of the blade gradually decreases to the point, which affects its strength. Knives with a tanto blade or a modified tanto blade, as well as knives with a reinforced point, are free from this drawback. The disadvantage of the last type of knives is the complexity of their sharpening.

Usually the edge of a clumsy knife is on the axis passing through the center of the knife. Knives with a raised point are also widespread, much less often with a lowered one. The raised tip facilitates the concentration of effort in a certain place, and the lowered one - to get a neat straight cut of the material on a hard surface.

Blade blade is formed by descents and carts. Descents can be straight (the best option, combining the strength of the blade and good cutting properties), concave (excellent cut, but low strength) and convex. Usually, the descent profile is symmetrical on both sides of the blade. In classical Japanese knives, an asymmetrical form of descents is used - the so-called “chisel”. However, when performing most of the works, this form of blade section is inferior to the classical symmetric one.

One of the problems in restoring a blunted blade is precisely maintaining the grinding angle along the cutting edge. To facilitate this process, the American company Miltner Adams Co has developed a special blade profile, HollowFlat Blade, used in the tactical knives of this company. A feature of this profile is a specific "side" on the blade. When sharpening the blade blade is parallel to the surface of the grinding bar.


The blade itself can be straight, convex or concave. The straight blade is the most functional and convenient to perform most of the operations performed with a knife. It also just sharpens.

The pronounced convex part of the blade is called the belly (or belly) and provides a concentration of cutting force on a limited part of the blade.

The concave (sickle) blade allows you to rip the cut surface.

The convex and concave shape of the blade is most often used in combat and tactical knives, as well as in knives for personal self-defense.

In addition to the classic smooth (plain) sharpening the blade there is a sharpening in the form of teeth or waves. In total there are five types of such sharpening: micro nose, teeth, wave, hacksaw and with shock teeth.

Micro pliers (micro serrations) are a notch on the blade (A), which is performed in the process of making a knife with a figured cutter. At the same time, the size of the microtoot does not exceed 1 mm

Micro pliers on the blade make it easier to work with solid materials (frozen foods). In addition, such a knife, having lost the ability to cut, will still be able to "cut."

A blunt blade with micro-pliers can be sharpened by restoring its cutting abilities, but the micro-pliers on the blade will be lost.
This type of sharpening is sometimes mistakenly called "laser". It is often used in kitchen knives (along the entire length of the blade), and sometimes on survival knives and bayonet knives (on the part of the blade at the handle, including on the butt). Quite rarely, such sharpening is located in the front of the blade. Such an arrangement facilitates penetration of dense tissue.

Gear sharpening - serreytor (from the English. Serrated - toothed, serrated) is a series of mini-concave blades (B) with a tooth size from 1 to 5 mm. Unlike folding knives, on which the whole blade can have such a sharpening, in inconsistent it occupies only a part of the blade near the handle (sometimes on the blade's butt).

Compared with a smooth cutting edge, serreytor has several advantages:

due to the fact that the cut occurs at different angles, it facilitates cutting of fibrous and laminated materials - ropes, ropes, cables, braid, cardboard, etc .;
the blade retains its cutting ability longer;
material cutting is faster due to the fact that with the same blade length the length of the cutting edge with the serrer is longer.

These advantages have to be paid for by the unevenness of the cut, inconvenience, or even the impossibility of performing a number of household tasks, the difficulty of restoring such sharpening. Due to the asymmetry of the blade section with a significant effort to cut the blade can lead to the side.

The areas of such sharpening are tactical knives, survival and self-defense knives, scuba diving and rescue knives, kitchen knives.

The most widespread form of serreytorny sharpening, developed by specialists of the company "Spyderco", in which two narrow teeth are alternated by one wide.

Special sharpening tools are used to restore dull serreitor sharpening, and this work presents certain difficulties for a beginner.

Micro-toothed and gear sharpening can significantly improve the weak cutting ability of knives with plastic blades.
Undulating or scalloped sharpening (scalloped) is characteristic of kitchen bread knives (B).

A hacksaw sharpening, or sharpening "saw teeth" (saw tooth), is a series of triangular teeth, the ends of which, unlike the serritory sharpening, are located in two planes (D). It is this sharpening that makes it possible to cut wood and is used in hiking and survival knives.

The shock teeth on the blade are large sharpened teeth on the blade's butt (D). Their purpose - the application of torn wounds to the enemy. They were used on combat knives, but are now rarely found. In some models of knives you can find a decorative version of shock teeth - a series of slots or grooves on the butt of the blade.

The role of shock teeth in some way can perform serraytor or hacksaw sharpening.

A variety of hunting knives designed for skinning animals (skinners from the English skin - skin, leather), on the butt of the blade has a special device - skinning hook. A similar hook have diving blades, but its purpose is different - cutting ropes, ropes and cables.

Butt (obushok) - the side of the blade opposite the blade. Usually awkward knives have a butt thickness from 1,5 to 10 mm. The thicker the butt, the stronger the knife, but its weight increases and the convenience of cutting various materials deteriorates. Knives with a thick butt are sometimes called crowns.


Knives designed for people who are fond of archery, crossbow or underwater hunting, have a special figured cutout on the heel of the blade, which facilitates pulling out the stuck arrows or harpoon.

Daly - longitudinal notches on one or two sides of the blade. In common parlance they are often called “blood vessels”. But they have nothing to do with bloodletting. Their purpose is to lighten the blade and increase its lateral stiffness. Sometimes, in pursuit of originality, the manufacturer makes them through, but the result is a weakening of the mechanical strength of the blade.

In front of the blade of the bayonet-knives (sometimes in survival knives) you can find a small through oval hole. With it, the blade of the bayonet joins the scabbard, forming wire cutters.

Semicircular cuts from the side of the blade at the edge of the blade and the handle. A small notch in front of the fifth blade with a diameter of 1 – 3 mm (“pulley”) is used for ease of sharpening the blade. A larger semicircular cutout is called a subfinger hollow or subfinger radius. It is intended for the index finger of the hand and serves to facilitate the removal of a knife stuck in a dense material.

“Thumb print” (thumb print) - an oval area on the heel of the blade, covered with shading. It is designed to rest your thumb while holding the knife with fencing grip. For the first time such a constructive element was used on the famous V42 dagger of American special forces units from the Second World War.

Such a "fingerprint" can be found on the limiter or the handle of mini-knives for self-defense.

The inscriptions on the blade. Known knife companies can put on the blade its logo, the name of the country where the knife was made, the type of steel, the model name of the knife, the facsimile of famous knife craftsmen, etc. On inexpensive knives these inscriptions are painted or stamped. More expensive models use etching or engraving.

In addition, the blades of survival knives may have different markings - goniometric and / or measuring, the scale of the rangefinder and so on.
Author:
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  1. Vladimirets
    Vladimirets 23 January 2014 09: 06
    +5
    "Unlike fixed-blade folding knives, they have a number of advantages:
    they are always ready to work - no need to open a blade that can jam due to contamination of the hinge;
    they are reliable in use - there is no risk of spontaneous folding of the blade due to defect, contamination or destruction of the knife fixing mechanism. "


    I would add a higher overall structural strength. Good article.
    1. cth; fyn
      cth; fyn 23 January 2014 09: 43
      +1
      and with time, the folding knife breaks loose.
      1. kavad
        kavad 23 January 2014 20: 57
        +1
        He walked with the Mongoose for six years, until he drowned. Actively used. Nothing was loose! The shape of the blade only changed, otherwise it seemed too hunchbacked.
  2. avt
    avt 23 January 2014 10: 37
    +5
    Quote: cth; fyn
    and with time, the folding knife breaks loose.

    And at the same time, a worn mechanism at the most inopportune moment reveals a reptile. laughing Okay on the belt, so in the summer in your pocket. So I left one folding man without mechanics, I still pull it up once a year and switched to a “crowbar”, well, for special occasions there is a simple, small hatchet, but for the front exits - a shovel.
    1. Astrey
      Astrey 23 January 2014 17: 35
      +1
      Over time, the folding knife becomes fixed.

      I dare to notice.
  3. core
    core 23 January 2014 12: 58
    +1
    the knife is also dull. so that fold, that one-piece blade, all one hand requires. By the way, knives with a lock have long been sold, and there isn’t any problem with opening in your pocket. maybe of course you guys live in the Caucasus and it’s normal for you to walk with a knife on a waist belt, and in our country in Bashkiria just under the white handles take the protocols to write. so it’s a plus +++ secretive wearing. and in terms of speed of bringing into a fighting position, the cleaver clearly lags behind the fold, while you get out of the sheath. but there’s also a big minus, I don’t recommend paving stones, I’m breaking it.
    1. avt
      avt 23 January 2014 13: 31
      0
      Quote: core
      maybe of course you guys live in the Caucasus and it’s your norm to walk with a knife on a waist belt,

      A man without a knife that Gypsies without a horse and the Caucasus has nothing to do with it, you can easily walk around Moscow with a folding bag, and a crowbar for tourists, in the summer, of course, it is not advisable to wear an open belt.
      Quote: core
      And in our Bashkiria, right under the whites, little hands take away the protocols.

      Well, so what and how to wear it, with a large certificate, again if not, then you definitely need to familiarize yourself with the law and TU defining what is edged weapon and not turn on the bull when talking, but speak politely, with an equal voice and confidently, well, when you hit , stubbornly agree to an examination, indicating in the protocol your opinion on the belonging of your knife to a household household or tourist tool with specific references to legislation. But you should always remember the words of "Iron Felix" - "The absence of a criminal record is not your merit, but our fault." It concerns not only the carrying of a knife, by the way, a folding mechanism with a folding mechanism, and even in conjunction with a lock, just in 99% falls under the article prohibiting its wearing, at least where. Well, bringing into a working position depends on manual dexterity and convenient for owner wearing, not the tricks of the folding mechanism.
      1. core
        core 23 January 2014 14: 41
        +1
        I didn’t say that they’re bribing, but an hour or two veins will be pulled, and everything is according to the law. and with regards to the lock, I did not mean the lock of the open blade, the lock of the eject mechanism. and still nice people, not everyone lives in the center of a big city, where there are all sorts of human failures and knowledge of the laws. in areas everything is different. and your knowledge of the law will not help (the police don’t know the law) and acts the old fashioned way, first take it and then figure it out. I make knives myself, and where can I get all sorts of certificates there? folds do not work.
        1. avt
          avt 23 January 2014 16: 09
          0
          Quote: core
          I make knives myself, and where can I get all sorts of certificates there?

          The certificate is given only by the examination of the Ministry of Internal Affairs, they decide - a weapon or a household. In your case, you need to know the by-laws, they have by-laws TU, it’s written there, it’s useful to refer to it in the case. But with regards to the blade retainer, so in conjunction with the flick mechanism with the lock, you definitely can’t stop it.
  4. Black
    Black 23 January 2014 13: 11
    +2
    Thanks to the author for the article.
    Good review.
  5. SPLV
    SPLV 23 January 2014 13: 51
    +1
    lighten the blade and increase its lateral rigidity

    Just make it easy! It is impossible to increase rigidity with longitudinal lobes, only to reduce its losses, compared with a decrease in the thickness of the entire blade. When will this battered fake stamp disappear from the blade articles?
    1. core
      core 23 January 2014 14: 43
      -1
      depending on what fraction, if the edges are rounded, then there is no stiffness, and if the angles, then the strength increases. What is a stronger corner or I-beam?
      1. Bigriver
        Bigriver 23 January 2014 15: 31
        0
        Quote: core
        depending on what fraction, if the edges are rounded, then there is no stiffness, and if the angles, then the strength increases. What is a stronger corner or I-beam?

        Tradition, most likely, has a place to be. Swords were hefty valleys. But there they really significantly facilitated the wedge.
        Again, different nations - in different ways. Finns, Germans, and different basurmans have dales on those knives that hint at possible military use. And in traditional Russian knives there are no dales.
        Yes, and on the HP-40 it is not.
        1. core
          core 23 January 2014 15: 47
          -1
          a lot depends on the quality of steel knitting or brittle. Russian knives are viscous steel, require constant sharpening, a working knife, have worked sharpening, dol as such is not needed here, such knives do not break.
  6. nekromonger
    nekromonger 23 January 2014 14: 17
    +1
    I do not accept folding knives, for me they are more likely a tool, not a knife.
    1. core
      core 23 January 2014 15: 43
      +4
      the knife is not a weapon in the literal sense, the knife is precisely the tool in the first place. a shovel is also a tool, but it can be applied differently.
  7. bear
    bear 23 January 2014 18: 27
    0
    great article
  8. Kir
    Kir 23 January 2014 18: 46
    +4
    Again Fomin "surprised", a lot of information but not processed. Yes, and brought myths. Let's start:
    1 Teflon and Teflon, this is not the same Teflon is a copolymer of Teflon and styrene, and its appearance is due to the fact that Teflon does not have adhesion, and as a result is not suitable as a coating, for this I had to pay resistance to temperature of Teflon 500, against 260 at teflon
    2 Then there are many more types of CTO than given
    3 In terms of alloying, well, where does the binding of Tungsten and Molybdenum to stainless steel come from, they are included in the cutter
    4 V-Titanium, which is often used for caprices already for 420 degrees, it loses its properties, hardness is just according to some sources at a maximum of 54HRC, forgive the price, but this whistle is about 8-10 higher price, but more expensive but not so, look at knives for scuba diving, cases of duplication of stainless steel models more often than 40X13 (its analogues 420) in titanium are not rare.
    5 About a hook for extracting something there is a suspicion that this is about a "shock hook" - a sling cutter, but they need to be able to use it, since there are good friends among the "diving".
    6 Damascus, so forgive the drawing by etching and showed it, this one and the other plastic blade will still have a hardness of 54-56HRC (see spring, spring)
    7 About the lamellar, and in Us they have long been known.
  9. uzer 13
    uzer 13 23 January 2014 19: 07
    +2
    Melee weapons are considered daggers with a blade length of more than 50 mm, for folding spring knives, the blade length should be no more than 90 mm. (Insanity and only). In case of problems it is necessary to require an examination. There should already be taken into account the shape of the handle and the method of fastening, configuration and the hardness of the blade. If there is no guard, the recess for the fingers is less than 5 mm, the edge of the blade above or below the longitudinal axis is the basis not to consider the knife as a cold weapon. If, of course, the examination is qualified.
    1. Kir
      Kir 23 January 2014 20: 52
      +1
      Have you noticed that often on the information sheet and the fact that you have in your hands are not 100% similar? Regarding the location with respect to the axis of the sting, it was from the evil one that I had one chance to explain that a lot with a reverse grip just does not have such a value.
    2. vkrav
      vkrav 25 January 2014 20: 46
      0
      Quote: uzer 13
      In case of problems, it is necessary to require an examination

      At least 1500 UAH ... And I have not heard that at least once the result of the examination was in favor of the owner.
      PS Double Shadow - handsome! Useless, but aesthetically pleasing!
  10. Yankuz
    Yankuz 23 January 2014 22: 44
    -1
    Thanks to the author - a great informative article!