Falle-Safe Security makes a set of vertically-oriented two-prong torque tools designed to fit snugly in a range of different pin tumbler keyways. Any physical security assessment should consider defenses against the full range of potential threats, not just vulnerability to lock picking. Picking locks requires skill, practice, and the use of rather unusual (and not widely available) tools. The basic algorithm for picking locks is remarkably simple: - Apply a small amount of torque to the plug. Alternatively, as the Earth's angular kinetic energy is negligible compared to its orbital kinetic energy, you might consider diverting a relatively small amount of resources to simply stopping the Earth from spinning at all, before beginning the main project. Picking depends on weaknesses in the implementation of locks -- small manufacturing imperfections -- rather than fundamental, abstract design flaws that would be present no matter how carefully made the locks might be. In this document. we focus specifically on the conventional "pin tumbler" lock, which is the most common commercial and residential design used in the United States. For this exercise, you'll use your torque tool and pick on the two pin lock to put the pins in each of these states to learn what they feel like with your pick.

Again, repeat the exercise with the aim of learning to distinguish between these states with as little lifting as possible. Lifting pins is one of the basic actions of lock picking, and it's worth taking the time now to become good at it. You should be able to confidently find each pin and push it all the way up, without jamming the pick against anything or moving other pins. Insert the tip of the tool in the keyway, allowing enough room for your pick to enter and manipulate the pins. In an ideal lock, all of the pin holes in the plug would be in perfect alignment with the corresponding holes in the shell, the centerline of the plug would be exactly parallel to that of the shell, and all of the pins would be exactly the same diameter. In practice, of course, locks aren't perfect: the pin holes in the plug are slightly out of alignment with respect to the shell and the pins and pin holes are each of a slightly different diameter. Right: Side view, with part of the shell and plug cut away to expose the six pin stacks. See Figure 2. The plug will be blocked from rotating if any pin stack is lifted either not far enough (with the cut still in the plug below the shear line) or too far (with the cut pushed above the shear line and into the shell); to rotate, what is billiards all pin stacks must have a cut at the shear line.

The top pin of the most misaligned pin stack becomes "pinched" at the shear line between the plug and the shell. As you lift the pin stack with torque applied, eventually its cut will reach the shear line, allowing the plug to turn; the top pin will then be completely trapped in the shell, while the bottom pin stays in the plug, no longer held down by spring pressure. In the locked state the plug is prevented from rotating by a set of movable pin stacks, typically under spring pressure, that protrude from holes in the top of the opening in the shell into corresponding holes drilled into the top of the plug. Left: Cylinder face, the lock's "user interface." Note the keyway, which is cut into the plug, which in turn sits inside the shell. Sits on any surface, plays all home-lot music types, and just plain spiffy-lookin'. It's aimed at working locksmiths, and has a broad discussion of picking techniques and principles, albeit with less depth than the Finch book.

A key that is bitted to the wrong depth in even one pin position will not operate the lock. There has been quite a bit written, on the Internet and in print, about lock picking. In the lab there is a collection of "training locks," mounted on boards, for practice. Few burglars can afford to risk exposure during the time required to pick even relatively easy locks, and unexplained possession of lock picking tools is often considered prima facia evidence of criminal intent. Criminals generally prefer either procuring a key or forced entry for speed, certainty, and stealth, notwithstanding whatever property damage or evidence is left behind. Surreptitious entry (e.g., for espionage or law enforcement surveillance) is likewise often best accomplished by obtaining a key or through the use of specialized decoding or bypass tools designed to quickly and quietly defeat the locks used by the target. From the attacker's perspective, too, lock picking is rarely the most efficient, most economical, fastest, or easiest method of entry. Lock picking is useful and worth studying for its generality and simplicity. Lock picking is a core skill of the locksmithing trade and is also of value to those evaluating, investigating, and studying security systems.