A key duplication is simply the process of making an identical copy of a key, whether it’s your apartment key or your car key. It’s a common service offered at many locksmiths, and even in some large retail stores such as Walmart or Home Depot. Using the right tools, this is relatively easy to do and can save you time, money and hassle in the long run.
Whether you’ve lost your keys or accidentally locked yourself out, the last thing you want to do is break a window or pry open the door and damage the lock itself. This is why it’s always best to keep a spare key and have a locksmith make one for you in case of an emergency.
The simplest way to get a duplicate is to visit your local locksmith or home improvement store and have them use their state-of-the-art machine that can cut a blank key in just minutes. These machines use laser-scanning to determine the type of key and its depths, and then cut a duplicate in the exact same shape. These are capable of replicating most pin tumbler keys, including the ones used to unlock doors and padlocks, as well as transponder keys and RFID key cards or chips.
While this method is quick and easy, it’s not the most foolproof. Certain keys are designed to be difficult to copy, which is why they’re often stamped with “Do Not Duplicate.” This may deter some people from attempting to duplicate them, but it doesn’t necessarily provide a foolproof barrier against someone who wants to try.
A more complicated and labor-intensive option is to take a cast of your key and then mold a copy from it. This was how keys were duplicated decades ago before the advent of the modern key duplication machine, and it’s still a viable method for some users. This can be done with anything from molded clay to soap bars and even bubble gum, but it isn’t as durable or reliable as a key copied on an industrial key cutting machine.
This method of duplication is also only effective for pin tumbler keys, not other types of keys or models that have a different design. If you have a restricted keyway, it’s extremely unlikely that it can be duplicated without breaking the lock itself. In addition to being difficult to find, these keys are often protected by patent laws or subject to hefty fines from their manufacturers.
A recent paper by UC San Diego graduate students Kai Wang and Stefan Savage, presented at the ACM Computer and Communications Security conference in Alexandria, VA, offers a more technological approach to key duplication. The team’s code utilizes a digital camera, MatLab and key-scanning algorithms to decode the pins in a key. The authors’ hope is that this method will be of value to researchers working on new encryption and authentication techniques. They’ve made their code available online so anyone can download it and test it out for themselves.