What are Lever Tumbler Locks?
With a lever tumbler lock, the lock mechanism features a pack of levers which are utilised to keep the bolt in position inside the lock. With the most basic types, lifting the tumbler to a specified height is required for the bolt to move.
Varying numbers of levers are used for different locks but odd numbers are generally used. This is to ensure that the lock can be detached from different sides of the door or case cover, and also provide symmetry. In some jurisdictions, a specific number of levers are required in order to adhere to security standards.
The Lever Tumbler Lock is a variant of one of the first locks ever used. In some places they are known as deadlocks and lever mortice sash locks. They are
as 2 and 3 lever locks and 5 lever locks.
How Does Lever Tumbler Locks Work?
A lever tumbler lock involves a series of levers, usually between three and five, that must be pushed into the correct height for a bolt to be released. The key for this lock type is bitted and pushes the levers into the correct position in order for the door to be opened.
Lever Tumbler Design
The levers, which are the foundation of the lever tumbler locks, are made from metals (usually non-ferrous types). The main chamber of the lock is crafted by working it into various depths in order to achieve the different combinations. In some cases, the lever meeting point is cut in different locations to get differs. The locks typically have designated pockets to allow passage of the bolt stump in the unlocking process. Although the standard lever tumbler locks are designed to work with a bitted key, some of the designs in other parts of Europe are crafted to work with double-bitted keys.
What Is The History Of Lever Tumbler Lock?
The first lever locks were invented in 1778 by English man, Robert Barron and were referred to as “Double Acting” tumbler locks. The design of these first locks required the lever to be lifted to a certain height by a slot cut in the lever. This meant that excessive or under lifting of the lever didn’t open the lock. The first lever locks are still in use till date in some parts of Britain and Eastern Europe. They can also be found on safes and gun cabinets in different parts of the world. Currently, however, the rise in the number of cheaper lock options have led to a decline in the popularity of lever tumbler locks.
How Much Do Lever Tumbler Locks Cost?
A typical lever tumbler lock will cost between £40 and £70 depending on the manufacturer and number of levers. This is just the price of the unit as the installation costs will vary across locksmiths. The key to getting the best value is to buy approved locks from approved dealers and then compare rates across local locksmiths for the best installation deals.
How Secure Are Lever Tumbler Locks?
As is the case with most locks available today, these type of locks are vulnerable to pickers, bumping and impressioning. The picking tool used is known as the curtain pick. Placed into the lock’s keyway, force is used on the locking bolt. The lever inside the lock is moved to the correct height for the locking bolt to pass through using the lock pick.
There is the possibility of drilling lever locks. However, a template or stencil will be required for the drilling point to be marked out. This is because the lock mechanism is normally mortised into the door. This makes it difficult to work out the right angle to start drilling from.
Today, there are lots of more secure lever tumbler locks in the market. The most popular type, the variant with 5 levers, comes with notches combined on the levers. The notches grab the bolt and then helps to prevent against moving in the process of lock-picking. This protective mechanism can be likened to the security pins deployed in standard pin locks. Different variations of the lever tumbler lock have been designed with enhanced security.
Speak to an experienced locksmith today to find out the best lever tumbler locks for you.