Indeed, security system software may well be considerably worse, since it is often purpose-written and may be subject to only limited scrutiny and testing. Worse, they often omit the designs that are of the most practical value. Unfortunately, these designs are less than ideal, and many of the "standard" picks are too large to fit and move comfortably in common lock keyways. See Figures 3 and 4. Once you're comfortable with the AR1 keyway, move on to the "Ilco SX" keyway locks and repeat the exercise. See Figure 1. (In practice, the cuts are produced by stacking pin segments of particular lengths, not by actually cutting the pins; hence the term "pin stack.") With no key in the lock, all the pin stack cuts rest within the plug. 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, all pin stacks must have a cut at the shear line.

When a key is inserted into the keyway slot at the front of the plug, the pin stacks are raised within the plug and shell. Rotation of the plug within the shell operates the locking mechanism. Picking these locks involves putting torque on the locking bolt and raising the gates to the correct height. Other names for the torque tool are turning tool, torque wrench, torsion wrench, and tension wrench. If you tried to rotate the plug of such a lock without a key in the keyway, the top pin segment of each pin stack would block the plug at exactly the same number of degrees of rotation; each pin stack would contribute equally to preventing the plug from turning. Repeat until lock turns: - Locate the pin stack that's being pinched at the shear line (it resists slightly when pushed up) - Continue to push that pin stack up until its cut reaches the shear line and the plug turns slightly.

For those unfortunate neo-anti-Luddites who refuse to acknowledge the value of anything not available on the Web, I suggest, at a minimum, reading the MIT Guide to Lockpicking, which, while not perfect, has the virtue of being free (and readily available online). Picks probe and lift the individual pin tumblers through the keyway, while torque tools control the degree and force of plug rotation. Pin tumbler lock picking consists of raising the cuts on each pin stack to the shear line, one by one, until the plug turns freely. The basic design consists of a rotatable cylinder tube, called the plug, linked to the underlying locking mechanism. Left: Cylinder face, the lock's "user interface." Note the keyway, which is cut into the plug, which in turn sits inside the shell. 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. In general, what is billiards wafer lock picking employs the same techniques and tools as those used for pin tumbler locks.

Many experienced locksmiths and expert lock pickers prefer "home made" tools to the commercial selections, especially for picking unusual and high security locks. Although somewhat romanticized by popular media and culture, in reality the significance of lock picking is usually dwarfed by other, more practical threats. If you inadvertently push a pin up too far or are applying so much torque that more than one pin is binding, you may have an overset pin instead. The multiple peaks allow several, or even all, pin stacks to set simultaneously. If you're having trouble, you may be pushing adjacent pins up past the shear line as you pick a pin, causing them to be overset even before they start to bind. Small digits represent short bottom pins (that must be pushed up more to reach the shear line); large digits represent longer bottom pins (that need only be pushed up a bit). There has been quite a bit written, on the Internet and in print, about lock picking. They allow very precise control over torque, especially when employing advanced picking techniques that involve a slight reversing of the rotation of the keyway.