Lesson 1: Introduction to Locksmithing - Part 1History of the Lock(smith)
It appears that lock technology developed independently in several areas across the globe, however, the oldest known lock was found in Persia and is said to be about 4000 years old. The lock found in Persian is similar to pin and tumbler locks in existence today. A large beam was set horizontally across the back of the door and engaged with the frame of the house. A vertical bar contained pins which engaged with the crossbeam. A hole in the door allowed for someone to reach inside and unlock the door using a key. The key was made out of wood and had pegs on it which corresponded to the pins inside. The key would lift the pins into position, allowing the wooden beam to slide open, disengage itself from the interior frame and unlocking the door.
It appears that lock technology developed independently in several areas across the globe, however, the oldest known lock was found in Persia and is said to be about 4000 years old. The lock found in Persian is similar to pin and tumbler locks in existence today. A large beam was set horizontally across the back of the door and engaged with the frame of the house. A vertical bar contained pins which engaged with the crossbeam. A hole in the door allowed for someone to reach inside and unlock the door using a key. The key was made out of wood and had pegs on it which corresponded to the pins inside. The key would lift the pins into position, allowing the wooden beam to slide open, disengage itself from the interior frame and unlocking the door. Combination padlocks were comprised of a lock body, rotating wheels, and a sliding bolt. The rotating wheels were engraved with letters or numbers. Both the wheels and bolt had convex and concave shapes engraved into them and were designed so that when the right combination of letters or numbers was selected it would create a chute which allowed the bolt to slide free.
Early European locks were not able to provide great access control. Early European locks started as a wooden beam across the back of the door, locking the door only when someone was inside the house. Early Greek doors pivoted at the middle, and locks involved a crossbeam bolt across the door which was tied shut with an elaborate knot. There was a hole in the door so that anyone adventurous enough to try and untie the knot could gain access to the home, however; locks had a spiritual significance attached to them. It was considered a great taboo to open someone else’s lock. Later, the Greeks adopted the Roman form of door lock, which used spring loaded bolts and held its pins inside a metal casing.
In the 14th century, Locksmith guilds began to form. They officiated who became a locksmith. The test to become a master locksmith was to build a working lock and key. These locks were for display purposes and were often elaborate and ornate. The locksmith guild regulated prices and techniques, and discouraged technological development. As a result, few innovations were made at this time. The first locksmith treatise, titled, The Art of the Lock, was published in France in 1767. This book describes several types of locks in service at the time, yet the inventor of the lock is still unknown.
Three key figures in 18th century England became instrumental in to the development of lock technologies. Robert Barron corrected the shortcomings of previous lever tumbler locks with the development of his own lever tumbler lock. His design forms the basis of lever tumbler locks still in use today. Joseph Brahman wrote A Dissertation on the Construction of Locks, which exposed weaknesses and vulnerabilities in locks previously believed to be ‘theifproof’. In his dissertation Brahman revealed that someone could easily make a key for Robert Barron’s lever tumbler lock by observing a set of grooves on the bottom of the lever. Barron integrated Brahman’s advice into the development of his next lock, a barrel shaped lock which integrated the rotating element into the lock. Jeremiah Chubb’s detector lock improved upon Barron’s designs. The detector was a 4 pin lock in a radial design that used a cylinder key. It had a mechanism built in to signal when someone had attempted to falsely manipulate the lock to gain entry. The lock was considered unpickable until 1851.
American lock makers had patented more than 3000 different locks before 1920, many of which improved and expanded upon European lock technology. At this time lock technology was making advances in rekey-able locks and removable tumblers. Lock housing which concealed the locking mechanism became more frequent. An American locksmith named Alfred C. Hobbs revolutionized lock-picking techniques. Previous to Hobbs, people opened locks by impressioning a series of false keys. This process was incredibly lengthy, often taking hundreds of hours. Hobbs’s technique utilized manual dexterity. He applied pressure on the bolt while manipulating the internal mechanism with a small pick inserted into the keyhole.
The Yale Company established a new standard in the lock making industry when it patented the Yale Mortise Cylinder Lock. The lock had a high level of security and could fit on doors of varying thickness. It could also be easily rekeyed and mass produced. From here cylinder development slows down. The Yale Mortise Cylinder standardized lock cylinders in North America.
Despite the standardization of the cylinder, there were still a lot of inventions to be made in locking technologies. In 1833 The Blake Brothers received a patent for the doorknob. The Jimmy Proof door lock was invented in 1916 by Samuel Segal. In 1920 Frank E. Best received a patent for an interchangeable core. 1928 saw the patent of a device from Schlage which integrated a locking mechanism with the doorknob, becoming the first knob-type lock with mass appeal. In 1933 Chicago Lock Company developed tubular key locks which became the premise for locks used on vending machines and bike locks. In 1967 the Mechanical Development Company brought about high-security lock technology with the introduction of the Medico cylinder. The cylinder used a restricted keyway, a sidebar, and angularly bitted keys and pins. The keys needed to lift the pins and rotate them into place to allow the sidebar to retract and open the cylinder – this made picking and impression the device much harder. Series Navigation