Glossary of locksmithing terms

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This is a glossary of locksmithing terms.

Contents

Glossary

Bible
The bible [1] is the part of a pin tumbler lock that contains the pins and pin stack springs as well as the pin stacks themselves. The driver pins of a pin-tumbler lock are located in the bible.
Bit
The section of a key which enters a lock, which has the key cuts formed in it and which engages the bolt or tumblers of the lock. The bit is called a blade in the case of a cylinder key. [2]
Bitting
The bitting of a key is the physical arrangement of the bit of the key that engage with the locking mechanism. The bitting instructs a locksmith how to cut a certain key, to replace a lost key or make an additional copy.
Blade
The segment of a key which enters the keyway of a lock and has key cuts machined into it. On a bit key the blade is called a bit. [3]
Bolt stump
In lever tumbler locks, a bolt stump is a rectangular part located above the talon, and passes through the slot in the levers as the bolt moves. [4]
Bottom pin
In a pin tumbler lock, the bottom pin is in contact with the key. It has varying lengths, corresponding to the key's bitting cuts. The bottom pin is also known as the key pin.
Break
A break in the pins is a separation in one or more sections of the pin used to encode the lock for a specific key or set of keys in a master keying system.
Driver pin
See top pin.
Dual custody
A dual custody locking system is one where two different keys, generally given to different people, are required to open the lock. These are often used in safe deposit boxes. [5]
Face plate
A metal plate on the lockset itself (on the door, not the jamb) is called a face plate.
False gate
A false gate is a mechanical element on levers in lever tumbler locks or discs in disc tumbler locks to make the lock more difficult to pick.
Glass relocking device
A glass relocking device is a piece of glass, usually tempered, placed where it might be expected to break in a burglary attack. It is attached, usually with wires, to one or more spring-loaded bolts, which are often randomly located. A drill or torch may break the glass, releasing the bolts.
Key cut
A square, rounded or V-shaped depression, filed or machined into a key, to allow the key to turn in its lock. In pin tumbler locks, the series of key cuts on a key causes the pins to line up at the shear line or gate so the lock will open. In warded locks, the key cuts bypass the wards so the key can push or pull the bolt. [6]
Key pin
See bottom pin.
Lock housing
The lock housing is the part of the lock that does not move when the lock is opened. It is responsible for transferring the action of the key to the bolt. [7]
Master pin
In a pin tumbler lock, a master pin is an optional, usually short, disk-like pin placed between the top and bottom pins. Its purpose is to allow two differently-cut keys to open the lock. Master pins are also called master wafers.
Plug
The plug is the part of a cylinder lock which is designed to turn when a key is inserted.
Plug follower
A plug follower is a device used in the assembly and disassembly of locks; it is a solid cylinder that is used to push the plug out of the lock, while preventing the springs and driver pins from moving. [8]
Relocking device in a safe Safe Relocking Device.jpg
Relocking device in a safe
Relocking device
A relocking device (RLD) (a.k.a. "external relocker") is an auxiliary locking device intended to be activated during an attempted burglary of a safe or vault. Such a device will keep a safe or vault locked even if the primary lock is defeated. This independent mechanism is designed to maintain the locked state of a safe even if the lock itself is destroyed. This auxiliary locking device usually consists of a spring-loaded bolt of some type, held in check by a bracket or cable that is rigged to release the mechanism in a burglary attempt. The device will either block the main boltwork from retracting or block the door from opening. Glass relockers are one of the most common types of relockers used in today's safes. Relockers are typically designed for one-time activation, meaning that once they are triggered the device is locked "permanently" and can only be opened by brute force.
Security pin
A security pin is a pin designed in a non-standard way to make picking the lock more difficult. [9] Examples of security pins include serrated pins, spools, and mushroom pins. [9]
Shear line
In a cylinder lock, the shear line (also known as the split line in Australia), is where the inner cylinder (plug) ends and the outer cylinder begins. When a break in the pin is reached by picking, the pin will "hang" at the shearline due to the space between the inner and outer cylinder. This "imperfection" in the lock mechanism is an unavoidable defect in the manufacturing process that allows for lock picking.
Snib
A snib is a device to engage or disengage a lock without the use of a key. In Scottish English or Irish English, the word is sometimes used as a synonym for lock. [10]
Spool pin
A spool pin is a type of security pin used to prevent picking in a pin tumbler lock. The pin is shaped like a cable reel. [9]
Strike plate
A strike plate is a metal plate affixed to a doorjamb with a hole or holes for the bolt of the door. When the door is closed, the bolt extends into the hole in the strike plate and holds the door closed. The strike plate protects the jamb against friction from the bolt and increases security in the case of a jamb made of a softer material (such as wood) than the strike plate. Some strike plates have their hole size and placement calculated so a spring-bolt extends into the hole, but an adjacent anti-retraction device remains depressed, preventing the bolt from being retracted unless the lock is turned.
Talon
The part of the bolt of a lock upon which the key presses as it is turned. [11]
Thermal relocking device
Designed as a defense against torch attacks, these are simply relocking devices equipped with a fusible link designed to melt and release the relocking device if the temperature inside the door exceeds a certain temperature (usually 65 °C), as would happen in a torch attack.
Top pin
In a pin tumbler lock, the top pin is in contact with the spring and interferes with the rotation of the plug when no key is inserted. The top pin is also known as the driver pin.
Warding
The grooves and protrusions of an irregularly shaped keyhole and/or the internal passage of a lock that requires a key be of a certain shape to be inserted.

Related Research Articles

<span class="mw-page-title-main">Locksmithing</span> Science and art of making and defeating locks

Locksmithing is the science and art of making and defeating locks. Locksmithing is a traditional trade and in many countries requires completion of an apprenticeship. The level of formal education legally required varies from country to country from none at all, to a simple training certificate awarded by an employer, to a full diploma from an engineering college, in addition to time spent working as an apprentice.

<span class="mw-page-title-main">Lock picking</span> Manipulating the components of a lock to unlock it without the original key

Lock picking is the practice of unlocking a lock by manipulating the components of the lock device without the original key.

<span class="mw-page-title-main">Warded lock</span> Type of keyed 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.

<span class="mw-page-title-main">Pin tumbler lock</span> Lock mechanism

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

<span class="mw-page-title-main">Disc tumbler lock</span> Finnish lock design

A disc tumbler or disc detainer lock is a lock composed of slotted rotating detainer discs. The lock was invented by Finnish founder of Abloy, Emil Henriksson (1886–1959) in 1907 and first manufactured under the Abloy brand in 1918.

<span class="mw-page-title-main">Combination lock</span> Type of locking device in which a sequence of symbols, usually numbers, is used to open the lock

A combination lock is a type of locking device in which a sequence of symbols, usually numbers, is used to open the lock. The sequence may be entered using a single rotating dial which interacts with several discs or cams, by using a set of several rotating discs with inscribed symbols which directly interact with the locking mechanism, or through an electronic or mechanical keypad. Types range from inexpensive three-digit luggage locks to high-security safes. Unlike ordinary padlocks, combination locks do not use keys.

<span class="mw-page-title-main">Tubular pin tumbler lock</span>

A tubular pin tumbler lock, also known as a circle pin tumbler lock, radial lock, or the trademark Ace lock popularized by manufacturer Chicago Lock Company since 1933, is a variety of pin tumbler lock in which a number of pins are arranged in a circular pattern, and the corresponding key is tubular or cylindrical in shape. Most locks use between six and eight pins, although some use as few as four or as many as ten. The devices have been widely used on vending machines, elevators, public computers, and bicycle locks.

<span class="mw-page-title-main">Lock and key</span> Mechanical or electronic fastening device

A lock is a mechanical or electronic fastening device that is released by a physical object, by supplying secret information, by a combination thereof, or it may only be able to be opened from one side, such as a door chain.

<span class="mw-page-title-main">Lever tumbler lock</span> Type of lock

A lever tumbler lock is a type of lock that uses a set of levers to prevent the bolt from moving in the lock. In the simplest form of these, lifting the tumbler above a certain height will allow the bolt to slide past.

<span class="mw-page-title-main">Mortise lock</span> Lock with mortise cut into doorjamb

A mortise lock is a lock that requires a pocket—the mortise—to be cut into the edge of the door or piece of furniture into which the lock is to be fitted. In most parts of the world, mortise locks are found on older buildings constructed before the advent of bored cylindrical locks, but they have recently become more common in commercial and upmarket residential construction in the United States. The design is widely used in domestic properties of all vintages in Europe.

<span class="mw-page-title-main">Door furniture</span> Items that are attached to a door or a drawer to enhance its functionality or appearance

Door furniture or door hardware refers to any of the items that are attached to a door or a drawer to enhance its functionality or appearance.

<span class="mw-page-title-main">Safe-cracking</span> Process of opening a safe without either the combination or the key

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

<span class="mw-page-title-main">Rotary combination lock</span>

A rotary combination lock is a lock commonly used to secure safes and as an unkeyed padlock mechanism. This type of locking mechanism consists of a single dial which must be rotated left and right in a certain combination in order to open the lock.

<span class="mw-page-title-main">Padlock</span> Portable locks with a shackle that may be passed through an opening

Padlocks are portable locks with a shackle that may be passed through an opening to prevent use, theft, vandalism or harm.

<span class="mw-page-title-main">Bitting (key)</span>

Bitting is the depth of key cuts on a cylinder key for a pin tumbler lock, often expressed as a number. Bitting also refers to the combination of key cuts on a bit key for a warded lock or lever tumbler lock.

Rekeying a lock is replacing the old lock pins with new lock pins.

<span class="mw-page-title-main">Lock bumping</span> Lock picking technique

Lock bumping is a lock picking technique for opening a pin tumbler lock using a specially crafted bump key, rapping key or 999 key. A bump key must correspond to the target lock in order to function correctly.

<span class="mw-page-title-main">Wafer tumbler lock</span> Type of lock

A wafer tumbler lock is a type of lock that uses a set of flat wafers to prevent the lock from opening unless the correct key is inserted. This type of lock is similar to the pin tumbler lock and works on a similar principle. However, unlike the pin tumbler lock, where each pin consists of two or more pieces, each wafer in the lock is a single piece. The wafer tumbler lock is often incorrectly referred to as a disc tumbler lock, which uses an entirely different mechanism.

The term protector lock has referred to two unrelated lock designs, one invented in the 1850s by Alfred Hobbs, the other in 1874 by Theodor Kromer.

<span class="mw-page-title-main">Magnetic keyed lock</span> Type of mechanical lock

A magnetic keyed lock or magnetic-coded lock is a locking mechanism whereby the key utilizes magnets as part of the locking and unlocking mechanism. Magnetic-coded locks encompass knob locks, cylinder locks, lever locks, and deadbolt locks as well as applications in other security devices.

References

  1. "What Is A Lock Bible?". Apex Security. 15 Sep 2018. Retrieved 23 Nov 2021.
  2. Keith Mayers (1979), A Dictionary of Locksmithing (PDF), p. 3, ISBN   0-9604860-0-3
  3. Keith Mayers (1979), A Dictionary of Locksmithing (PDF), p. 4, ISBN   0-9604860-0-3
  4. Mick Friend (2004), The Encyclopaedia for Locksmiths, Authors OnLine, Ltd., p. 34, ISBN   0-7552-0117-5
  5. "What Is a Safe Deposit Box?". NerdWallet. 31 October 2016. Retrieved 2 November 2018.
  6. Keith Mayers (1979), A Dictionary of Locksmithing (PDF), p. 35, ISBN   0-9604860-0-3
  7. "Lock Housing with Bolt". Historical Locks. Retrieved 23 Nov 2021.
  8. Ollam, Deviant (2012). Practical lock picking : a physical penetration tester's training guide. Syngress/Elsevier. pp. 102–106. ISBN   978-1597499903.
  9. 1 2 3 "Security Pins". Art of Lock Picking. 24 February 2016. Retrieved 8 October 2018.
  10. "snib | Definition of snib in English by Oxford Dictionaries". Oxford Dictionaries | English. Archived from the original on September 14, 2017. Retrieved 1 November 2018.
  11. "snib | Definition of talon in English by Your Dictionary". Your Dictionary | English. Retrieved 4 March 2020.