Locksmith - Safe and Lock

Minkle Lock and Safe Co., Inc - Located on NYC's Staten Island in New York state. We serve the greater New York City metro area's Safe and Lock needs. Please enjoy this informative article.

Locksmithing is the science and art of making and defeating locks. A lock is a mechanism that secures buildings, rooms, cabinets, or other storage facilities from theft by burglars. A key is usually used to open a lock. It is often said that "a lock keeps honest people honest."

Practitioners are called locksmiths. Locksmithing is one of the earliest forms of security engineering. Lock-picking was one of the first methods of cracking security systems.

The issue of full disclosure was first raised in the context of locksmithing.

Warded lock

A warded lock is a type of lock that uses a set of obstructions, or wards, to prevent the lock from opening unless the correct key is inserted. The correct key has notches or slots corresponding to the obstructions in the lock, allowing it to rotate freely inside the lock. Warded locks are commonly used in inexpensive padlocks, cabinet locks, or other low-security applications, since they are among the most easily circumvented by lock picking. A well-designed skeleton key can successfully open a wide variety of warded locks.

Warded lock History

The warded lock is one of the most ancient lock designs still in modern use. It is thought to have been developed in ancient Rome.

Warded lock Design

In the most basic warded lock, a set of obstructions, often consisting of concentric plates protruding outwards, blocks the rotation of a key not designed for that lock. Warded locks may have one simple ward, or many intricate wards with bends and complex protrusions; the principle remains the same. Unless the notches or slots in the key correspond to the wards in the lock, the key will strike an obstruction and will not turn.

A cylindrical post is typically located in the center of the lock. Its purpose is to provide a point of leverage for rotating the key, and to help correctly align the key with the wards. The key has a corresponding hole which fits over the post.

When the correct key is inserted, it will clear the wards and rotate about the center post. The key may then strike a lever, activating a latch or sliding bolt, or it may itself push against the latch or bolt. In a double action lever lock, the key may additionally push against a spring-loaded lever which holds the sliding bolt in place.

Cylinder lock

A cylinder lock is a lock in which a cylinder must rotate in order to open the lock. The cylinder may be held in place by a variety of locking mechanisms; some common mechanisms in modern use include the pin tumbler lock and disc tumbler lock

Combination Lock

A combination lock is a type of lock in which a sequence of numbers is used to open the lock. The sequence may be entered using a single rotating dial which interacts with several discs or cams, or by using a set of several rotating discs with inscribed numerals which directly interact with the locking mechanism.

Combination Lock Design

One of the simplest types of combination lock, often seen in low-security bicycle locks, uses several rotating discs with notches cut into them. The lock is secured by a pin with several teeth on it which hook into the rotating discs. When the notches in the discs align with the teeth on the pin, the lock can be opened.

This lock is considered to be one of the least secure types of combination lock; many locks of this type can be opened without knowledge of the correct combination. Opening one in this fashion depends on slight irregularities in the machining of the parts. Unless the lock is machined precisely, when the pin is pulled outward, one of the teeth will pull more strongly than the others on its corresponding disc. This disc is then rotated until a slight click is heard, indicating that the tooth has settled into the notch. The procedure is repeated for the remaining discs, resulting in an open lock, and a correct combination, in very little time.

Combination locks found on padlocks or safes may use a single dial which interacts with several parallel discs or cams. Customarily, a lock of this type is opened by rotating the dial clockwise to the first numeral, counterclockwise to the second, and so on in an alternating fashion until the last numeral is reached; the cams typically have an indentation or notch, and when the correct combination is entered, the notches align, allowing the latch to fit into them and open the lock.

Combination locks of this type are generally more secure than the type described above, but some of them do have weaknesses. For example, early combination padlocks made by Master lock could be cracked by pulling on the shackle of the lock and turning the dial until it stopped; each numeral in the combination could be revealed in this manner. More recent models of Master padlock with a 40-position dial have a mechanical weakness that can give away the last numeral in the combination, and the first two numerals have a mathematical relationship with the last number. This weakness reduces the number of possible combinations from 64,000 to a mere 100, which can be tried in a relatively short amount of time. Inexpensive padlocks are often susceptible to the use of a padlock shim, which can be used to release the shackle without entering a combination.

Pin Tumbler Lock

The pin tumbler lock is a lock mechanism that utilizes a group of pins of varying lengths to prevent opening the lock without the correct key. Pin tumblers are most commonly employed in cylinder locks, but may also be found in tubular or radial locks.

Pin Tumbler Lock History

The basic principles of the pin tumbler lock may date as far back as 2000 B.C. in Egypt; the lock consisted of a wooden post affixed to the door, and a horizontal bolt that slid into the post. The bolt had vertical openings into which fitted a set of pins. These could be lifted, using a key, to a sufficient height to allow the bolt to move and unlock the door.

Inventor Linus Yale, Sr. patented a cylindrical pin tumbler lock in 1848, a design which was further improved and patented by his son, Linus Yale, Jr., in 1861. Yale, Jr.'s design is very similar to pin tumbler locks manufactured today.

Pin Tumbler Lock Design

The pin tumbler is commonly used in cylinder locks. In this type of lock, an outer casing has a cylindrical hole in which the plug is housed. To open the lock, the plug must rotate.

The plug has a straight, shaped slot known as the keyway at one end to allow the key to enter the plug; the other end may have a cam or lever which activates a mechanism to retract a locking bolt. The keyway often has protruding ledges which serve to prevent the key pins from falling into the plug, and to make the lock more resistant to picking. A series of holes, typically five or six of them, are drilled vertically into the plug. These holes contain key pins of various lengths, which are rounded to permit the key to slide over them easily.

Above each key pin is a corresponding set of driver pins, which are spring-loaded. Simpler locks typically have only one driver pin for each key pin, but locks requiring multi-keyed entry, such as a group of locks having a master key, may have extra driver pins known as spacer pins. The outer casing has several vertical shafts, which hold the spring-loaded pins.

When the plug and outer casing are assembled, the pins are pushed down into the plug by the springs. The point where the plug and cylinder meet is called the shear point. With a key properly cut and inserted into the groove on the end of the plug, the pins will rise causing them to align exactly at the shear point. This allows the plug to rotate, thus opening the lock. When the key is not in the lock, the pins straddle the shear point, preventing the plug from rotating.

Tubular pin tumbler lock

A tubular pin tumbler lock is a variety of pin tumbler lock in which the pins are arranged in a circular pattern, and the corresponding key is tubular or cylindrical in shape. Locks of this type are commonly seen on bicycle locks and vending machines.

Disc Tumbler Lock

A disc tumbler lock or wafer lock is a type of lock that utilizes a set of flat discs to prevent the lock from opening unless the correct key is inserted.

Disc Tumbler Lock Design

In a cylindrical disc tumbler lock, a series of flat discs or wafers holds a cylindrical plug in place. The discs are fitted into vertical slots in the plug, and are spring-loaded, causing them to nestle into a wide groove in the outer casing of the lock. This groove blocks the discs from rotating, which in turn prevents the plug from rotating.

A rectangular hole is cut into the center of each disc; the height of the holes in the discs vary in size, so a key must have notches corresponding to the height of the hole in each disc in order to open the lock.

When the correct key is inserted, the discs are raised to a height sufficient to allow them to clear the groove in the outer casing. The discs must not be raised too high, or they will enter a second groove on the opposite side of the casing, preventing the discs from rotating. When all the discs are clear of both grooves, the plug, along with the discs and key, may rotate.