What installation errors do not allow the lock to turn the key
Installing a door lock is quite complicated and not easy. To carry out quality work, you will need certain skills and special tools. The vast majority of problems with doors arise due to improper installation of locks. Failure to comply with the installation instructions, lack of knowledge of the technology or, most often, negligence, lead to premature wear and breakage of locks.
The most common problem is seizing or the complete inability to turn the key in the lock well. There are several reasons for this. The very first is the inaccurate installation and use of tools. Metal or wood filings, shavings, and scale resulting from welding can easily get inside the lock case. Usually this leads to disruptions in the mechanism that does not allow the key to be turned. Moreover, such a problem can arise both on the first and on the second turn of the key.
Very often, due to negligence, mixing or skewing of the lock case inside the door is allowed. This causes a shift in the axis of rotation of the key, the impossibility of its rotation and jamming. Also, the skew of the lock case can cause the mismatch of the bolt with the hole in the mate of the counterpart. Because of this, the key cannot be turned more than half a turn and the door is locked.
The inability to rotate, skew and jamming the key may occur due to the mismatch of the lock cylinder with a hole in the door. This usually happens with level locks, as in cylinder mechanisms the larva is on the surface of the door.
Quite typical are problems arising from improper installation of the counterpart of the lock. It is mounted in a door jamb, while the holes in the metal plate must exactly match the axis of movement of the lock bolt. Displacement of the hole even by a few millimeters will not allow the bolt to enter the pad and, accordingly, turn the key in the keyhole.
A similar reason arises with insufficient depth of the hole for the bolt, drilled in a wooden jamb. The crossbar does not enter the mating part of the lock completely, which entails a turn of the key by only one revolution. The same nuisance can occur when the counterpart is clogged with metal or wooden shavings.
To avoid such troubles, you should take the door lock installation yourself more seriously, or invite a competent specialist for this.