For the lock larva: characteristics and description

In some locks, in the event of a cylinder failure, you have to purchase the whole assembly, but most of the mechanisms simply allow you to replace the damaged part. To change the larva in the castle, special skills are not needed, it will also be much cheaper than buying a new locking device.

Causes of breakage

The functioning of the lock may be violated in the following cases:

• The design contains a defective part. It should be noted that the devices must be manufactured by established firms and implemented in proven stores - so you can minimize the likelihood of buying a substandard product.
• The prolonged operation of the device led to the wear of the larva. There are no perpetual mechanisms, therefore each of them has a certain period of use, after which the lock starts to work badly and there is a need to repair or replace the entire element.
• The door was tried to open with an unsuitable key, because of this the picklock, which was used when trying to open it, can get stuck inside the cylinder or break.
• The latch of the door lock is initially installed incorrectly. In this case, it is necessary to re-assemble the device and carefully observe the technology of the work.
• Damage to the door leaf or its deformation from exposure to high humidity. Sometimes it is necessary to change not only the locking device, but the entire door. The core should be replaced only with an insignificant degree of deformation, to which the mechanical effect on the structure, for example, impacts, resulted. In other cases only more radical methods can help.

Varieties

For the lock, the larva consists of a number of elements, such as spring-loaded pins, plates and balls. There are several types that differ in the closing method, the most common are the following:

• Two-sided option - is more secure and optimally suited to apartments or houses for the castle. The larva is blocked if the key is inserted into the structure from the inside of the room.
• Half a cylinder. In this case, you can close or open the lock only from the outside of the door.

For the larva: how to choose

It is worth to be careful when choosing a new device and to be guided by the main criteria, which include the manufacturer, type of construction, diameter, width and length of the cylinder. The last parameter should be suitable for the dimensions of the installed locking device and the door leaf itself. From the surface of the door to the end of the core should be no more than 2-3 mm. If this rule is not observed, the probability of opening the lock increases. In the case of a minimal threat of dissection, you can limit yourself to a standard inexpensive item.

The cylinder must also be suitable for the type of lock. The surface design on one side has a rotary knob, and on the other - a hole for the key. The mortise version of the well is on both sides.

It is worth paying attention to the manufacturer who released the existing lock device. The products of many companies have certain sizes and are used with standard cores. The generally accepted standard has the following parameters: diameter - 17 mm, width and length - 10 mm and 34 mm, respectively. The larval groove in this case has a drop-shaped shape.

In order not to have to return the non-approached goods back to the store, it is necessary to measure the dimensions of the cylinder, having previously dismantled it from the structure. But it is best to bring the core to the store so that the consultants can pick up a similar product.

How to remove the larva of the castle and install a new one

In order to pull the defective element out of the lock, it is not necessary to remove it. To perform the work you need a screwdriver, in its absence you can use a conventional screwdriver.

On the front of the structure is a screw, which ensures its fixation on the door leaf. Most often it is located next to the larva itself. Beforehand it is necessary to open the lock so that the lock bolts do not interfere with the process. Then the key must be turned so that it touches the core, and pull it out. The latch of the lock of the entrance door should move slightly. If everything remains as before, you still need to twist the key until the part starts moving freely.

When using an overhead lock, the element is removed from the side of the handle. In a mortise design it can be pulled out in any convenient direction.

In some cases, the task is complicated by the presence of decorative overhead parts or additional handles. They must also be removed by unscrewing the locking fasteners for the lock. The larva can be removed with a screwdriver or other thin tool available. The process can be simplified by applying a special lubricant, for example WD-40.

Installation of a new element

As noted above, the new core is selected in accordance with the dimensions of the door and the type of lock installed. The assembly of the locking device does not cause complications and consists in carrying out the manipulations carried out earlier, but already in the reverse order. After the larva selected for the lock is installed, it is necessary to check the functioning of the structure and make sure that all the parameters are met. The position of the cylinder is fixed with a bolt, and do not overdo it when tightening it. As well as insufficient twisting, this will lead to a malfunctioning mechanism. At the end of the work, the handle and decorative lining are mounted.

What you need to know

The task can be carried out by any person, as you can pull out the larva from the lock without using special tools. The cylinder determines the correct operation of the entire device, so it must be selected in accordance with the size of the element that is out of order. Also, you need to show maximum accuracy when installing, because damage to the internal design of the lock will lead to the need for its replacement.