The lock closes one turn, but on the second it starts to jam

The client's name and some circumstances have been changed.

Let's call the client Nikolai. Previously, he always closed the door two full turns of the key. Over time I noticed something strange. The first revolution was performed normally.

On the second, the key began to move much harder. If you apply some force, the lock sometimes closes completely. Nikolai began to simply leave the door closed one turn.

“If the first revolution works, maybe this is enough and the repair can be postponed?”

The problem here is that a change in the operation of the second revolution already indicates a malfunction or incorrect position of the elements.

Why does one revolution work, but the second does not?

With each subsequent revolution, the crossbars move further. If there is a problem with:

• counter holes;
• door position;
• box geometry;
• internal mechanism;
• lock drive;

it can only appear at a certain stage of movement. The first revolution passes freely, but on the second the crossbars encounter resistance.

How to tell if the problem is in the door or lock

A useful check is to carefully test the mechanism with the door open. If both turns are easy when the door is open, but when the second one is closed it begins to jam, there is likely a problem with the alignment of the crossbars and the counterpart.

If the second turn is heavy even with the door open, attention should be paid to the mechanism itself.

Why you can’t constantly press the key by force

Additional load is transferred to:

• key;
• drive;
• crossbars;
• internal parts of the lock.

Over time, this may result in a complete failure.

Is it enough to close only one turn?

The design of a particular lock is designed for a specific operating mode. If previously the mechanism normally performed two revolutions, but now one of them has become inaccessible, it is better to eliminate the cause rather than consider the new operation the norm.