What are the larvae for door locks. What should be the lock cylinder of the front door

The working part of the lock is a larva, it is also a CMS (cylinder mechanism of secrecy). Actually, this is the lock cylinder of the corresponding system itself. Often the breakdown of the lock comes down to a malfunction of the larva, and you can limit yourself to replacing it. What are the larvae for metal door locks and how to choose the right one?

Lock cylinder device

The cylinder for a mortise lock consists of a cylinder with grooves. Spring-loaded plates are located in the grooves. The key (a metal blank with grooves) melts the plates. The cylinder rotates and drives the bolt mechanism. The door closes (or opens, depending on the direction of rotation).

There are many versions of this basic design. Pins (pins, plates) can be located horizontally, vertically, at an angle. Their number varies (it determines the level of secrecy), from two to thirty. There are double pins (one inside the other), magnetic, floating, etc. Cutting grooves on the key is performed for a specific larva (i.e., for the required number of pins, taking into account their location).

The more complex the larva of the door lock (the design and the higher the secrecy), the more difficult it is for the burglar to open the door in an intelligent way.

The main parameters of the larvae

1. Cylinder length.

2. Cam offset relative to the middle. Cylinders are versatile and equilateral. In the second, the cam is located strictly in the middle, in the first it is shifted to the side.

3. The presence / absence of a turntable. A larva with a turntable is more convenient: the door closes from the inside without a key.

4. The mechanism of secrecy.

There are three levels of secrecy:

Important: when choosing door larvae, special care must be taken. Usually, the mechanism is suitable only for its lock model, less often for several models of the same manufacturer.

Low - up to 5 thousand combinations;

Medium - up to a million;

High - up to 4 million.

Types of larvae

Larvae for door locks have features depending on which door the lock is installed on.

For entrance metal doors, mortise locks are most often used (they are installed in the end part of the canvases). Sometimes their variety is loose (practically the same, only without the front bar). Insert locks are more often used as auxiliary locks, as well as for internal locking (larva with a turntable). The cylinder-larva for the lock (mortise) is located in its body.

For wooden entrance doors (and for interior doors too), both mortise and overhead locks can be used. For overhead locks, the larva is attached to the lock cover or directly to the door.

A popular larva for a lock with a turntable and designed to be unlocked with a key on both sides.

Manufacturers and price

1. The price of a larva for the Mottura castle (Italy) starts from 7 thousand.

2. Mul-t-lock (Israel) - from 5 thousand.

3. Larva for Cisa castle (Italy) - from 8 thousand rubles.

4. Kale (Turkey) - from two thousand.

5. Apecs (China) - from 600 rubles.

Of course, modern locks are a reliable protection for your home. But in reality, it is not always sufficient. For complete security, we recommend that you also install a security system. Such a system, combined with good locks, guarantees you one hundred percent confidence and security. To install such a system, it is best to turn to professionals. We recommend paying attention to the company MK Krona. Security systems are their main profile. You can find all the information in the apartment security section.

Video "Replacing the door lock cylinder":

When choosing larvae for metal door locks, it is better to give preference to models with increased secrecy. Indeed, in our time, it is possible to crack an ordinary lock in less than a minute.

Helpful information

Mortise lock with latch for cylinder mechanism

A mortise lock with a latch for a cylinder mechanism is one of the most common types of locking devices. It is quite reliable and easy to use. This design provides for the possibility of replacing the larva, which will save on the purchase of a new locking mechanism.

As a rule, the reliability and quality of the inner larva as a whole determines the reliability of the lock itself. Therefore, you need to buy an internal mechanism only from trusted manufacturers, while taking into account the technical parameters of the cylinder. In the presented segment, the trademarks Elementis, Roto have proven themselves well - the TBM-Market catalog includes options of different sizes, with different types of larvae.

Entrance door lock larva buy in Moscow

A cylinder mechanism with a turntable is considered quite popular. It can be mounted on the front or interior door. But more often the cylinder mechanism for the lock is selected for entrance doors, because. at a relatively low cost, it provides reliable protection against hacking. A turntable is a special rotary handle that opens the lock from the inside without a key. At the same time, from the outside, a cylinder mortise door lock with a latch can be opened only with a key, like any other standard lock.

To buy a larva for a door lock, you must first measure the total length of the cylinder mechanism. This can be done independently using a regular ruler. If you plan to replace the internal device in an already installed lock, it is better to get the core and pick up a new one in the store that matches its size. If you have any difficulties in this matter, we are ready to advise you and help you with the choice.

We try to form the most complete assortment, so we are guaranteed to select the core for your castle. If necessary, we can offer high-quality door handles presented in the neighboring category.

Do you urgently need the best and most reliable lock cylinder? Do you have a lot of requirements for the front door and this functional element? Can't decide on the best cylinder model?
Then the advice from the article and the recommendations of the competent masters of "Zamki-SAO" will be very useful to you. Prices for door larvae are very different, however, not all products are good. Consider the main factors to consider when buying a part.

How to choose the best larva for the castle?

You can buy a larva in almost any specialized store. However, there are a number of aspects that need to be considered first. An ideal and reliable lock cylinder must necessarily meet increased requirements, including the following points:

The maximum level of secrecy.
Trouble-free operation, including with intensive use of the front door.
The best, highest degree of burglar resistance.
Ease of use of the lock.
Durability.
Resistance to intellectual and forceful influence.
Wear resistance and reliability.

Of course, there are other points that deserve consideration. In most cases, manufacturers of entrance metal doors install not the best larvae in locks. As a rule, these are elements of medium and low secrecy. If the larva or cylinder is the weak link of the lock, then even a complex crossbar system will be opened in a few minutes by thieves and other intruders.

The reliability and quality of the larva is also determined by whether it is able to withstand power hacking options, including drilling, knocking out, breaking. Of course, it is best to buy a cylinder from a foreign manufacturer, as it will be of better quality.

What is the most reliable larva for the front door lock - the best models

Nowadays there are a lot of reliable and good lock grubs that are able to withstand bumping. As a rule, these are cylinders of the highest price category. The masters of our service department will kindly advise you and help you choose the most reliable cylinder for the lock on the front door. The products of the following three manufacturers have gained the greatest popularity, namely:

Whatever cylinder secrecy mechanism you choose, you should give preference to certified products from trusted manufacturers. Simplifying the design while maintaining the burglar resistance of the larva is the course taken by the owners of many lock and hardware companies.

If you need the best larva for the lock, then our leading masters will be happy to select the most reliable model, taking into account the input locking mechanism and your wishes. Moreover, they change the lock cylinder in a delicate way, provide long-term guarantees for the cylinder and services. We have been working with burglar-resistant and imported models for years, so we always offer our customers the best options in terms of price and quality. We are waiting for your calls!

The larva is the code detail of the lock. When buying a lock, manufacturers provide the buyer with the right to choose the larva himself. The need to choose a larva also arises when malfunctions occur in the operation of the old mechanism or the key is lost.

The larva performs the protective function of the door.

Geometric parameters

First you need to decide which larva for the lock can be used in your case. If you see a through teardrop-shaped groove with a height of 34 mm, a width of the protruding part of 10 mm and a diameter of the rounded part of 17 mm, then the larva corresponds to the European DIN standard. Choosing a larva of this standard is both easy and difficult. On the one hand, any will do, on the other - the widest range. If the larva has any other shape, then there is no choice. Only a similar mechanism from the manufacturer of your lock will do. In extreme cases, it may be a Chinese replica of dubious quality.

Some locks from popular Israeli manufacturers Mul-t-lock and SuperLock stand apart. If the section is in accordance with the DIN standard, they may have a non-standard drive in the form of a gear, and not a cam, like other mechanisms. This is not a problem. Secret manufacturers complete their products with gear drives, so for such locks you can choose a larva of another brand.

The length of the inner and outer parts of the cylinders with the same cross section may be different. The length of the interior only affects aesthetics. The main thing is that the end of the secret is not recessed behind the pad of the lock or door handle. The length of the outer part is more important. In the absence of an armor plate in the design of the lock, the end of the secret must be flush with the bar on the door. A protrusion within 3 mm is allowed. The larger it is, the easier it is for an attacker to open the larva in a destructive way. If there is an armor plate, the end of the secret should come as close as possible to it.

The mechanism may be one-sided. The interior is usually devoid of secrecy. Turning is carried out without a key by the built-in handle.

Types of keys and quality of secrets

The easiest way to identify the mechanism is by the appearance of the key. Classic cylinders turn with an English key. A flat or shaped blade of such a key has a sawtooth toothed cut. Locking pairs of pins are located in the same plane. Most of these mechanisms belong to the budget segment. You can choose a budget larva with an English key for rooms where there is no high probability of opening, or in cases where you are forced to give the key to strangers.

A cross key indicates low tamper resistance. Despite the impressive appearance, only a few hundred combinations are used for this arrangement. The well is wide and convenient for the introduction of thieves' tools. You can choose a larva with such a key only “from good people”. Cross mechanisms are especially liked to be made in China.

The semi-circular disk key for DIN secrets is rare. The attitude towards such products is twofold. In most cases, these are very simple cylinders with low resistance and secrecy. But there are also very reliable products from the Finnish manufacturer Abloy. Because of him, such keys are called Finnish. Buy mechanisms of this type is worth it from Abloy.

The most serious protection is provided by mechanisms with a punch card key.

It has the form of a rectangular plate with a set of recesses and grooves. Such keys are usually inserted into the well horizontally and are double-sided. Larvae with these keys belong to the middle price category. Such secrets are not revealed by simple means. To penetrate, attackers use special equipment or destructive methods.

The most perfect keys are made on the basis of punched card keys. They add magnetic or electronic identifiers, combine different types of secrets. In addition to craters, the key may have lateral teeth, non-rectilinear grooves. Secret elements are placed offset from the vertical direction.

Exceptions are possible. You can choose a larva of different quality for any key design. If the type of mechanism is primarily responsible for secrecy, then the materials used for the manufacture of moving parts are responsible for the durability of the mechanism. It is better if all the most important elements are made of steel. The use of brass, silumin and other similar materials reduces the strength and reliability of the product.

Opening resistance

Many consider secrecy to be the main parameter of the cylinder. In fact, the concept of secrecy is very arbitrary. It refers to the number of element mates that must take a certain position to allow rotation. The simplest and cheapest cylinders have 4-5 pairs of pins, the point of contact of which must be exactly on the line of rotation in order for the core of the mechanism to rotate. In complex and expensive devices, the number of pairings that can be set reaches 12-13. The number of possible combinations characterizes, rather, the technological perfection of the design than its secrecy. It depends primarily on the quality of workmanship and process tolerances.

The number of groups of mating parts is not so important: the layout and relative position of these elements. Designers of cylinder mechanisms strive to make the work of a cracker as inconvenient as possible, make the well compact, give it a complex shape, place elements that interfere with the introduction of a thieving tool, arrange false moves and channels, place pins at an angle, give relief to contact surfaces, add the need for rotation, and so on. Mechanisms of an average level, even with a highly skilled burglar, cannot be opened quickly with master keys.

Attackers use automation techniques. The most famous of them is bumping. Bumping does not require any special qualification. It only needs a set of bump keys of different types. The workpiece is inserted into the hole, rotated slightly for preload, and then hits are made on the head of the workpiece key. The anti-vibration pins are set in position and the core rotates. Protection against bumping is ensured by the use of magnetic and electronic codes, telescopic pins, the execution of the larva without the use of springs. Such options are available only in expensive high-level models.

No less important is the protection against destructive opening methods, for this, various amplifiers, high-alloy steel grades and titanium alloys, additional locking elements are introduced into the design. The most secure cylinders are drill-proof.

The first English larvae for door locks appeared in the 19th century, but the removable design turned out to be so successful that they are still being produced to this day. Next, we will analyze in detail the 7 rules for choosing larvae, plus you will learn how to replace the larva in the door lock with your own hands in a few minutes.

You can replace the lock cylinder of the front door within a few minutes

Design features of castle larvae

The same models of locks are installed in both wooden and iron doors, but installing a lock in a metal door requires higher professional skills, plus an expensive tool. Therefore, it is easier for people to change the door lock cylinder, and leave the locking mechanism the same.

From the point of view of design, the larva of the lock of the front door can be of 3 types - disk, cross and cylinder.

Cylindrical larvae are also called pin, pin and English. Visually, they are not much different, and their principle of operation is similar.

The disk larva of the door lock opens with a semicircular key and itself has a round shape. The reliability of the disk mechanism leaves much to be desired, and replacing the door lock cylinder here takes more time. The only plus is the affordable price;

The door lock cylinder with a disc mechanism is more difficult to replace than a cylindrical model

A larva with a cross mechanism is equivalent in reliability to a disk one. The 4-sided cruciform key looks impressive, but the larva's device is extremely simple. To enter without a key, the robbers remove the pad, insert a Phillips screwdriver into the well and turn it with a powerful movement, after which the lock opens;

If a mechanism with a cross larva acts as the main constipation in a dwelling, then it is advisable to completely change the lock or install a more serious protection nearby.

The cross cylinder of the door lock can be cracked using only one powerful Phillips screwdriver

The cylinder-type mechanism is considered the most reliable, plus you can change the larva in the lock in a couple of minutes, and using only one screwdriver. In addition, English larvae have a number of advanced modifications that are quite difficult to drill or knock out.

Since robbers try to drill out the larva in every second case, most modern mechanisms are initially equipped with protection against drilling

In view of the low reliability, I see no reason to dwell on the disk and cross options. Although they are sold to this day, they are not very popular, so we will concentrate on choosing a cylinder mechanism, but first we will learn how to change the larva with our own hands.

How to replace the lock cylinder with your own hands

Even before disassembling the larva of the old lock, it is advisable to lubricate the mechanism of the new larva. For these purposes, a special silicone lubricant is produced, but if you feel sorry for the money for it, buy ordinary engine oil;

Before removing the door lock cylinder, it is advisable to lubricate the mechanism; for this, liquid types of engine oil are used.

When disassembling, enter the lock hole with the key, open it and leave the key in the neutral position;
Now we disassemble the mount. To do this, we need to unscrew the fixing screw. The head of the screw is located on the end plate of the lock, just opposite the larva. The screw is completely unscrewed and pulled out;
When the screw is out, the larva should come out freely;

If, after removing the fixing screw, the larva does not come out of the lock, try moving the key while trying to pull the larva. The locking cam should be in the zero position and then the mechanism will come out.

Do-it-yourself replacement of the front door lock cylinder is not particularly difficult even for a complete amateur

After removing the old larva, put a new one. If a new larva has not yet been bought, then take the old one, go to the store and ask the seller for the same one, then insert it into the lock and tighten the fixing screw;
Do-it-yourself replacement of the front door lock cylinder is over, you can use it.

Do not attempt to repair the mechanism yourself. For an amateur, do-it-yourself repair of a lock cylinder is extremely difficult. After assembly, you will have a lot of "extra" parts, plus the lock itself can be opened with any flat object that looks like a key. Only replacement of the cylinder will help here.

High-quality repair of the lock cylinder at home is almost impossible

According to the configuration, cylinder larvae are of 2 types:

Key plus key - the option when keys are inserted on both sides is good because if you stick the key in from the inside, you can’t open the lock from the outside;
Key plus wrapping - if a wrapping is installed inside instead of a key, then in case of a fire or some other emergency, it will not be difficult to quickly unlock the lock.

The complete set and type of the lock larva is determined depending on the specific situation

Pins are responsible for encoding the larva, they are also called pins, they are located at the bottom of the mechanism. Pins through springs enter the cutouts on the key, each pin corresponds to a given position, thus setting the level of secrecy.

In budget models, 5 pins are placed and secrecy is limited to ten thousand options;
In the middle price category, 6 pins are installed and the number of options increases to fifty thousand;
In expensive locks, 6 or more pins are placed, plus additional secrets, such as magnetic inserts. The number of options here starts from one hundred thousand, but usually manufacturers indicate several million.

The more pins are installed on the lock cylinder, the higher the level of secrecy of the mechanism

If the larva weighs around 100 grams, then you are dealing with a cheap model, the insides of which are made of aluminum or silumin. She won't last long. A high-quality product with a steel or bronze mechanism cannot weigh less than 180 grams, and the weight of some models reaches 250 grams.

By weight, you can determine the quality of the larva, the mass of a normal model starts from 180 g

It is impossible to visually see the protection against drilling of the lock cylinder. The fact is that such protection is provided by an internal insert and pins made of high-strength steel. The only advice that can be given in this case is to carefully study the accompanying documentation and choose a reliable manufacturer.

Protection against drilling is provided by steel inserts in the lock cylinder

Horizontal keyhole larvae have the same burglary resistance as their vertical keyhole relatives.

Bumping is called knocking out a keyhole with a heavy tool. The robbers put some kind of superstructure on the keyhole and hit it with a heavy hammer or sledgehammer, after which the larva flies into the dwelling, and without it, you can open the lock with any screwdriver.

Anti-bumping larvae can be recognized by the presence of a special steel bracket on the side of the mechanism. According to the manufacturers, this bracket is able to withstand heavy loads and will not allow the lock to be knocked out.

The steel bracket serves to protect against knocking out the larva with a heavy tool

It is not realistic to open a larva with magnetic protection with ordinary master keys. The fact is that one of the pins of such a larva is magnetized and it reacts to a reciprocal magnetic insert, which is built into the key, and the insert and the pin have their own potential and the first magnet that comes across, you cannot open such a lock.

Larvae with magnetic inserts are found in the middle and upper price categories

Determining the quality of a product by its cost is a risky business, a high price may be the result of transportation costs or the banal greed of a merchant, but still it is worth paying attention to this point.

Now the price for a normal larva starts from 500 rubles. If you are offered an item with fabulous protection at a bargain price, then it is either a fake or a stolen item;
Larvae with a price of 500 to 1000 rubles are of quite decent quality, in this case, this is the average price category;
Everything that is more expensive than a thousand rubles is already closer to an elite product, often the quality of such products is really high.

Notable lock manufacturers

Illustrations	Recommendations
	Mauer Such larvae are famous for their high protection against various types of master keys.
	Mottura Here, the designers have fully concentrated on high protection from knocking out, their anti-bumping system is one of the best. But the larvae from Mottura are not well protected from drilling.
	Riko and Asteks Trading Solid domestic manufacturers that produce goods of approximately the same quality. At the moment, in the middle price category, these brands have already reached the world level.
	Cisa Cisa has always been famous for its high-quality castle armor plates, but now they have released a line of no less high-quality larvae and have greatly pressed the aforementioned Mauer and Mottura on the market.

Conclusion

All the tips and recommendations described above have been repeatedly tested in practice and are guaranteed to work. In the video in this article you will find additional information on locks. If you want to add something to what has been said or ask a question, welcome to the comments.