Most of us at one time or another has lost our keys and know the stress that it causes. Compounding things is the cost that comes with calling out a locksmith to replace all the locks on the windows and doors of your house. But what if you could change your locks simply by inserting another key? That’s just what the Matrix Key System designed by Australian locksmith, Stuart Webb, does. Inserting a new key into the lock effectively changes the lock, rendering the old key useless and saving the hassle and expense of calling a locksmith.

Standard pin-tumbler locks are the most common form of locks in the world. They use pins of various lengths sitting in narrow chambers. When the correct key is inserted the pins are aligned to allow the barrel to turn and the lock to be opened. With standard locks the pins within pin-tumbler locks are of a set length. Meaning that one key will always open the lock and changing this will require replacing the cylinder in the lock – which is what a locksmith does when they change your locks.

A conventional pin-tumbler lock (Image: Pbroks13 via Wikipedia)

How it works

Webb’s Matrix Key System uses an ingenious method to allow the length of the pins to be changed by inserting a new key. Part of the pins are made from donut shaped discs of metal that sit in the bottom part of the chamber. Each lock has a series of keys – a typical set has between six and twelve keys but it could theoretically be more. When you wish to change the lock you grab the next key from the series, which will push some of the discs out of the way when it is inserted into the lock. These discs are then deposited in extra “spigot chambers” that are incorporated into the barrel when the new key is turned. Now the lock will only open to that key.

The extra â€œspigot chamber" incorporated into the barrel into which the discs are deposited

The new keys must be used in a specific sequence. This is because each key in the series will have incrementally higher ridges so that one or more pins are pushed above the shear line (the space between the barrel and the rest of the cylinder) when the key is inserted. Also, when incorporated into master-key systems, like those used in motels, each room can be changed individually without affecting the master-key or other room keys.

The system is illustrated in the pictures below. The “Phase 1” key (with the red dot) holds all the discs below the ‘shear-line’ and will operate like this indefinitely, just like a normal lock. The magic happens when a “Phase 1” key is lost or stolen; then the “Phase 2” key (green dot) is inserted and the uppermost disc is lifted above the ‘shear-line’ into the top part of the chamber, and as the key is turned the disc drops into a special hole which permanently removes it from operation, thereby preventing the missing “Phase 1” key from operating. The ‘Phase 3’ key will disable the ‘Phase 2’ key, etc etc.

The inner workings of the Matrix Key System

Webb says his Matrix Key System can be adapted to almost any pin-tumbler lock, making it suitable for just about anything including doors, garages and padlocks. His invention caught our eye when it appeared on the Australian ABC’s New Inventors program. Since then he has received a lot of interest from groups such as retirement homes, schools and councils.

The Northern Territory Govt. are also looking to install Matrix Key System locks on public housing to solve the problem of changing the locks every time a new tenant moves in. They are currently conducting a 3-6 month trial on 50 housing commission houses and plan to extend that to 2,000 homes in the Katherine area for another 3-6 month trial after that.

With its potential to take a lot of work from locksmiths, Webb might have more trouble convincing them to sell his Matrix Key System, but it can be purchased in a number of different lock types, including padlocks and replacement cylinders for existing locks, through his website.