Serving Watertown and the North Country

Interchangeable Core:

The advantage of interchangeable core locking systems is that it allows the end user to change the keying of a lock by the end user without the need of a locksmith. Interchangeable core also uses more secure keys, keys that are harder to copy or can't be copied. To change the core you simply insert what is called a control key that (often looks the same as the regular key) and turn a small amount and pull to remove the core. Interchangeable core is generally seen on stores, apartments, schools, office buildings, hospitals and government facilities. It is rarely seen on residential.

The customer normally has spare cores and keys that they can change the keying on a door on a moments notice without outside help. So if there is a security issue in one area the locks can be changed right then and it does not require any special tools with the exception of the control key and it does not require any special knowledge. Interchangeable core lock system costs more up front than a standard key system but can pay for itself in the ability of the customer to change their own locks.

Interchangeable locks can be master keyed the same as standard locks / non-interchangeable core. Most non-interchangeable core locks of commercial quality are 6 pin where as interchangeable core is available 6 pin or 7 pin.  A 7 pin system gives more master key capabilities and is harder to pick.  

Interchangeable core in small format was invented by Best and often is referred to as Best Cores. Best Lock Company is now owned by Dorma-KABA. These type cores are referred to as “Small Format Interchangeable Core” or SFIC and now available from several companies. Several companies make the same keyways and specifications of cores so they can be intermixed. Several companies also make locks to accept these cores. Other than the name on the front of the core seldom are there many differences.

Interchangeable is also available in “Large Format Interchangeable Core” or LFIC. The LFIC are generally brand specific and operate very differently then the SFIC but accomplish similar goals. The LFIC tend to wear better then the SFIC because the pins are larger. The LFIC is also required in some brands in order to have all the parts needed to function. LFIC is generally pricey than SFIC. LFIC is generally seen in Yale, Sargent, Schlage, Corbin Russwin and Medeco. With the exception of Medeco these companies are also offering SFIC to compete with the companies offering SFIC.

Medeco / KeyMark and KABA offer systems that will fit locks with standard cylinders and both SFIC and LFIC.

For Large Format Cores key control can vary to an easy to get a key that a hardware store may have to a fully patented restricted key.

For Small Format Cores key control can also vary greatly. The hardware stores generally only stock one keyway section and these keys can be difficult to copy. There are many different keyway sections from the relatively easy to get to quite difficult to get and the fully patented key is also available.

Just because a key says “Do Not Duplicate” or “It is Unlawful to Duplicate this Key” does not make it so. Key control is achieved by availability of key blanks and if they are patented with a valid patent. For more information on key control go to our section on High Security.

Interchangeable core locks have more parts. We sell several brands including KSP, Arrow, and we can get Best as well as some other brands. In large format we sell mostly Schlage but can get Medeco both current patent and expired, Corbin Russwin and Sargent.  

The “core” contains all the pins and springs for the key to function.

Note: The KABA L10 patented line of key control locks and keys that we sold are no longer available.