What is impressionning?
Impressionning is a lockpicking technique as effective as it appears magical!
To understand this method it is better to have assimilated the basics of lockpicking. Indeed impressionning consists in making the key of a lock instead of picking it. And of course, without knowledge of the lock or the combination of its key. This allows in addition to the opening of the lock, to get a fully functional key and therefore to be able to close and reopen it as many times as you want!
The tools needed to practice impressionning
This method requires a blank key corresponding to the profile of the lock, a vice clip to hold the blank, a half-round file grade Switzerland “2” and a magnifying lamp with 45x magnification.
Manufacturers sell this kit as well as a good number of blank keys.
The process is easy, once the blank key is inserted it will lower the active pins under the shear line, so it is no longer the passive ones that we will try to lower but the active ones that we will raise by filing the blank.
For this it is necessary to associate a rocking movement of the blank key with a rotating pressure, so the pins not yet placed will produce from their top a mark on the wire of the blank key. It is then enough to file at the location of these marks, but be careful, do not file too deep or you will exceed the shear line.
When the pins are positioned at the shear line they will no longer mark.
Here, we can clearly see the impressionning mark in the center of a previously filed location:
And now, it is by repeating this somewhat mathematical operation that we are guaranteed to obtain the opening:
In addition to obtaining a fully functional key! Here, the original key above the one obtained using the impressionning technique:
To go further
For an entry-level cylinder like here, this impression took 2 minutes, but on other systems you have to adapt. This complementary video, made during one of our conferences, clarifies some points and indicates some references:
You can watch the first video here (restricted to ACF members: log in to watch the video)
Many other methods exist and depending on the lock they will be more or less recommended. A variant of this practice is auto impressionning.
Usable on various systems, impressionning is developing more slowly than lockpicking. Yet it is a very effective technique that contains some subtleties so try it and it will open!