Screwsman

Safe-cracking is the process of opening a safe without either the combination or key.

Different procedures may be used to crack a safe, depending on its construction. Different procedures are required to open different safes so safe-crackers need to be aware of the differences.

Lock manipulation is the stereotypical safe cracking technique commonly portrayed in movies. It's a damage free combination recovery method, and a well known surreptitious bypass technique. Manipulation only requires fingers, eyes, and proper technique but it's a skill that takes years to develop and decades to master. Manipulation is a Group 2 mechanical lock bypass method. Expert practitioners of this art can open locks with speed and consistency. These professionals manually manipulate the lock in order to obtain the combination one number at a time. Manipulation procedures can vary, but they all exploit the same imperfections. Manipulation will unlock a safe and recover its combination. Once the combination is recovered it may be reused to open the safe lock. Similar damage free bypass can also be completed by a computerized auto-dialer. These auto-dialer machines are known to take 24 hours or more to reach the correct combination. In recent years faster devices have been engineered for lock bypass. These new devices use more advanced robotics and more advanced software. When used in cooperation with each other the two technologies closely mimic manual manipulation. This generation of niche robotics mimics manual manipulation because they can "feel," and measure mechanical movement within the lock. The newest dialers can manipulate.

Mechanical safe locks are manipulated primarily by feel, and vision. Sound also aids the process occasionally. To find the combination the operator uses the lock against itself by measuring internal movements with the dial numbers. More sophisticated locks use advanced mechanics to eliminate any feedback a technician could use to identify a combination. These group 1 locks were developed in response to group 2 lock manipulation and can be identified by the lack of feeling in the dial or by a push/turn dial. Wheels made from lightweight materials will reduce valuable sensory feedback, but are mainly manufactured as X-ray resistant locks. Manipulation is often the preferred choice in lost-combination lockouts, since it requires no repairs or damage, but can be time consuming for an operator, the specific difficulty depends on the unique wheel shapes and where the gates rest in relation to them. A novice's opening time will be governed by these random inconsistencies, while some leading champions of this art show admirable consistency. There are also a number of tools on the market to assist safe engineers in manipulating a combination lock open in the field.

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Wikipedia