Lock impressioning is a specialist locksmithing skill and one that takes hundreds of hours of practice to master. The art of lock impressioning is a non-destructive, covert method of making a working key for a lock without disassembling the lock or using lock picking techniques.
Impressioning techniques rely on the locksmith’s ability to bind internal components until they are in the correct position. The internal components are bound against a metal key blank to produce marks that indicate their positions are incorrect. Once a component is properly aligned, it should no longer bind or produce marks.
The general impressioning process is as follows:
- Obtain the correct key blank for the lock
- Prepare the key blank to enhance the markings to be obtained
- Insert the key blank into the lock, bind the components, and manipulate the key blank to produce markings on the key blank
- Interpret the markings on the key blank and remove material from the key where binding is suspected
- Repeat this process until all components are in the proper positions and the lock opens
The art of lock impressioning is not used as often in day to day locksmithing activities, but it is still considered a core locksmithing skill. It is also included in the locksmith training package, and it is still used in lock competitions all over the world.