Skeleton keys have always had a bit of mysterious allure about them and have been central objects in countless mysteries and detective novels. They have even reached movie stardom. Perhaps you’ve heard of The Skeleton Key starring Kate Hudson, Peter Sarsgaard, and Joy Bryan? Despite legends to the contrary, skeleton keys are not magical; they work on simple mechanical principles. So, let’s get the skeletons out of the closet and learn what these keys are all about.
What Is It?
If the words “skeleton key” bring up images of an old-fashioned key with a long neck and a rounded, sometimes decorative top, you are at least partially correct. There are two basic types of keys that are commonly called skeleton keys.
The Old-Fashioned Key – One of the first types of mechanical locks were warded locks. These are the ones featured in mystery movies. Many older pieces of furniture still feature smaller warded locks, but they have been largely eliminated because of their susceptibility to picking. Warded locks are long and hollow and are able to be seen through. In fact, the keyhole used to make a great way to peep in on someone behind closed doors.
The keys that fit in these channel-shaped locks were called skeleton keys. These keys were barrel-like, with a long, round shaft. Warded locks were invented by the Romans and are based on projections built inside the key hole. These projections would block flat keys or wrongly shaped keys from turning the lock. Instead, each lock had to have a key fashioned that matched the projections inside the lock. Despite the fact that locksmiths became very creative in the design of the projections (even featuring crosses and other figures), warded locks were relatively easy to pick. Thus, the skeleton key in this form has pretty much become relegated to the past, except when lore, mystery, and intrigue bring them back in print and to the screen.
The Master Key – Some people refer to a master key as a skeleton key. A master key is one that fits into a number of different locks in one facility – all of the rooms in a specific hotel. While individual keys are designed with channeling on them that enables them to open only one door, the master key has no channeling and can open any of the doors that have been designed to be opened by the single key.
Another type of lock, the pin-and-tumbler-style lock, is designed to be opened by two different keys, the single key for that door and the master key for a group of locks. This is accomplished by making a third pin next to a pair of pins. This third pin can be raised to one of two levels, depending on the key used.
How It Works
Whether you refer to a master key or the old-fashioned skeleton key, both work on simple principles of mechanics. No electricity, codes, or magic are involved in these locking mechanisms. The locksmith or manufacturer simply creates a lock that opens to a key that matches the mechanical parts of the lock, whether a set of obstructions inside the lock (warded lock) or a set of channels, pins, and tumblers.