A combination lock works differently from keyed locks. It opens by aligning its interior parts in a definite position rather than with a key. A combination lock is available in either a cylinder or mortise layout. It uses a numeric keypad requiring the numbers to be pressed in a sequence to release the latch.

Opening a basic combination lock is easy. All you need to do is know your combination. Then make a couple of turns, and the lock will open.

How does a simple combination locks work?

• Combination locks use a wheel pack, a set of wheels that work together to realize the combination.
• A combination lock consists of a combination dial attached to a spindle. Inside the lock, the spindle runs through several wheels and a drive cam.
• The number of wheels in a wheel pack depends on how many numbers are in the combination – one wheel for each number.
• As you turn the dial, the spindle rotates the drive cam. The drive cam is attached to a drive pin. As the cam turns, the drive pin makes contact with a small tab on the next wheel called the wheel fly.
• Each wheel has a wheel fly on every side. The drive pin spins the first wheel until it makes contact with the wheel adjacent to it. The process continues until all of the wheels are turning. This is called picking up the wheels.
• Each wheel on the spindle has a groove cut into it. When you dial the right combination, all of the wheels, and their slots align correctly.

How to Use a Combination Lock

When you purchase a simple add-on combination lock, the first thing you need to do is find the combination. It can be on a sticker on the back of the lock or on a separate sheet of paper that is included with the lock.

It is important to enter the figures given in the combination in the same order as on the combination tag.

Follow the instructions given below to open your combination lock.

• Turn the dial three times to the right. Then stop when the first number lines up with the indicator.
• Turn the dial one full turn to the left, passing the first number. Stop when the second number lines up with the indicator.
• Turn the dial to the right and stop when the third number lines up with the indicator.
• Either pull up on the shackle or pull the lock down to open the lock.

Make it a point to keep your combination in a safe place so that you do not forget it.

How Safe Are Combination Locks?

Simple combination locks are considered to be relatively safe. The main advantage of these locks is that there is no need for keys and power to open. Some brands even allow a metal key so that the combination can be overridden. They can be cut or possibly jimmied. These locks are really intended to be a temporary deterrent of theft of property (such as for a bike or gym clothes). We recommend that you do not rely on them to keep your valuables secure and if you must use them to secure a wallet or something equally important, try to be discreet. Don’t advertise that valuables are being stored with only the combination lock to secure it.

However, combination locks have their share of inherent flaws. The biggest one is a limited number of possible combinations. For example, a five button lock can have just 1,082 possible combinations.

Larger, more complex combination locks that use either electronic keypads or a dial combination, are more secure. They traditionally operate along the same principals as the simple combination locks we all are familiar with from high school, only on a grander scheme.

The electronic version allows you choose your own easy to remember combination, or to easily change the combination on a regular basis. It only allows for 3-5 consecutive incorrect entries before “locking down”, further enhances its security.

Dial combination locks of the same sturdy construction can last a really long time with proper care. They’ve been around for over 150 years and have proven successful in design and function. A downside could be that you have to call a locksmith in to change the combination, if that is desired.

A1 Locksmith of Palm Beaches (http://www.a1gmtlocksmith.com) is a leading provider of security related services and equipment in West Palm Beach with over 30 years in the business. They run a blog dedicated to all things security.