In addition to making picking more difficult, secondary locking mechanisms are sometimes also intended to make it more difficult to reproduce unauthorized copies of keys. Each wafer has a large rectangular cutout through its middle and through which the key passes; the precise height of the cutout keys the wafer to different bittings. Making keys for these locks often requires the use of special equipment and unusual, proprietary key blanks. This technique requires a great deal of practice to master, but has the surprising property of sometimes being more effective against better made locks. While pin-at-a-time picking is usually the most reliable way to open a given lock (and the skills used essential for mastery of other techniques), raking can sometimes open a lock more quickly. A few pin tumbler lock products orient the key horizontally in the keyway and use a flat key bitted with variable-depth holes ("dimples") rather than the cuts used for the familiar "sawtooth" key. While the pin tumbler cylinder is by far the most popular door locking mechanism in the United States, it is not the only kind of keyed lock in common use. Schlage SC is a very common keyway. Once you've mastered the AR1 keyway locks, repeat exercises 2 through 6 with the "Ilco SX" keyway locks.

Again, continue with the AR1 locks. These locks can be picked according to the same principles as used for ordinary pin tumbler locks, but, again, different tools are used to accommodate the different shape of the keyway. When the final (non-security) pin is set, the lock should open. The Y1 keyway is one of the toughest you are likely to encounter in real lock installations in the US. Now, what is the real world? And the real world is not an idea, it is not words. A crazy person might get by accident into some of these states, and get so lost that he wouldn’t know how to come back to the world of ordinary normal conventions. Once you've picked a cylinder, you should know in exactly what order the pins pick. But before we go into that, I just want to know if there are any questions; if I’ve made myself clear, and if there are any of you who find me utterly unintelligible? There are locks with two, five, and six pins in each keyway, but the keying codes aren't labeled on them. In a lock with six pin stacks with a uniform chance of a pin setting at either shear line, the probability of a picked lock actually opening is only 1/64. Picking techniques for these locks involve the use of special torque tools designed to put torque on only one of the two concentric plugs.

If just one pin sets at the "other" shear line, the lock will not open even though all the pin stacks are picked. In general, wafer lock picking employs the same techniques and tools as those used for pin tumbler locks. If the wafer is set too low by the key, it blocks rotation by extending out through the bottom of the plug, while if it is set too high, it extends out the top. Figure 6. Abus "spool" top pin. Practice distinguishing between the pin states and then finish picking the cylinder. Master keying does not introduce any significant complications for lock picking. The commercial lever lock mechanism dates back to the early 19th century Chubb lock (and, indeed, what is billiards to well before). The design is based on the late 18th century British Bramah lock (still in production and use today). Master ring cylinders (which are no longer in common commercial production but were once marketed by Corbin) use this mechanism to provide independently-keyed master keying. A common door lock mechanism in Europe uses a standardized "European profile" lock module.

This may be a consequence of more stringent European insurance standards for physical security. High security locks are more routinely installed in Europe than they are in the United States. An alternative technique, which I have not seen mentioned in the literature, is to first determine which pin stacks have security pins and which have regular pins (by picking normally and noting which stacks are false set). And, of course, electronic locks have at their root software whose size and complexity grows as they become more sophisticated (and as they are networked into centralized control systems). High-security locks often incorporate one or more secondary locking mechanisms beyond that provided by the conventional pin tumblers. When the energy transfers, the top pin moves up while the bottom pin slows down, and a gap is created between the two pins. The pins are at the bottom of the keyway rather than the top. Picking locks with spool and mushroom pins takes practice, both to recognize them and to effectively neutralize them when they are encountered. With practice, even this keyway will eventually seem easy to maneuver.