Interchangeable Core Basics

Use bottom pins that are manufactured of the same material as the original equipment keys. For example, use Brass pins with brass keys

The Best®/Falcon® type Figure “8” small format interchangeable core lock mechanism was developed so non-locksmith personnel could conveniently and inexpensively rekey a lock without any knowledge of how locks operate or how to service them. This concept, first patented by Frank Best in the...

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LAB has a Universal interchangeable core bottom pin design. This Universal design bottom pin is manufactured of full hard brass material. The chamfer .012” +/- .001” is thicker with a straight edged angle towards a smaller rounded nose. The included angle is 90 degrees with the nose .022” +/- .003”. The Lab Universal interchangeable core bottom pins are color coded to exact industry standards.

LAB Security Executive Vice President Jerry Roraback strongly suggests that before purchasing replacement pins for interchangeable cores, make sure you know whose cores you are repinning and the key blanks material. If you are using a nickel silver key blank and the cores are BEST, only re-pin with the BEST tumbler pin design. If your cores are not BEST but use nickel silver key blanks, use what LAB refers to in its product line as “LAB Original I. Core Pins” (for use in interchangeable cores: Falcon, Schlage Small format, Medeco Keymark, etc.) When repinning interchangeable cores with a brass key, LAB's color coded .108 diameter interchangeable core pins will function well.

Why the different bottom pin material? Lock manufacturers strongly recommend using bottom pins that are manufactured of the same material as the original equipment keys. Brass pins should be used with brass keys and nickel silver pins should be used with nickel silver bottom pins. Similar materials will cause even wear on both edges, whereas dissimilar materials will over time result in uneven wear on the softer metal object.

This leads to the cutting of interchangeable core keys. Interchangeable Core keys are cut to very tight tolerances. This is because there are only .0125” increments, smaller diameter pins and the cores are also made to tight tolerances.

When cutting interchangeable core keys, these tip stop keys are difficult to properly align. The Schlage SFIC uses a shoulder stop key. The blade is also thin and usually of paracentric design. As a result, the keyway has to be thinner because of the sectional applications. In addition, there are many different keyways.

This results in difficulty holding the key blank in position within a key machine key vise. One method of securing the key and key blank is to use paper clips and different pieces of wood or metal to better position the key and key blank blades for duplication and/or origination.

Rytan, a key machine manufacturer, has introduced Key Adapters that secure the specific keyway key blades in the proper position without distortion, when duplicating. The Key Adapters are designed to operate with most cylindrical key duplicating machines.

Without some type of assistance, what can and does often happen is the blade becomes distorted without the locksmith even knowing this problem is occuring. The distortion causes the cuts to be either too shallow or too deep and somewhat out of position. When the cut key is removed from the vise jaw, the blade straightens out somewhat changing the cut geometry.

This is why most interchangeable core manufacturers strongly recommend using punch style key machines to cut their IC keys. This way each key is an original rather than a duplicate.

For more information on interchangeable cores, contact your local locksmith wholesaler or:

Arrow Lock, Telephone: 800-839-3157 Fax 800-421-6615. Web site:

Corbin Russwin, 225 Episcopal Rd., Berlin , CT 06037 . Telephone: 704-283-2101. Fax: 800-447-6714. Web Site:

Falcon Lock Co., 2315 Briargate Pkwy #700 , Colorado Springs , CO 80920 . Telephone: 800-266-4456. Web site:

LAB Security, 700 Emmett Street , Bristol , CT 06010 . Telephone: 860-589-6037. Fax: 860-583-7838. Web site:

Medeco Security Locks, 3625 Allegheny Dr , Salem , VA 24153 . Telephone: 800-675-7558. Fax: 800-421-6615. Web Site:

SARGENT Lock, 100 Sargent Drive , New Haven , CT 06511 . Telephone: 800-727-5477. Fax: 203-821-5793. Web site:

Schlage, 111 Congressional Blvd., Suite 200 , Carmel , IN 46032 . Telephone: 800-847-1864. Web Site:

Yale Commercial Locks and Hardware, 100 Yale Avenue , Lenoir City , TN 37771 . Telephone: 704-283-2101. Fax: 800-338-0965 Web Site:

For more information on key adapters, contact your local locksmith wholesaler or Rytan, Inc., 455 Maple Avenue , Torrance , CA 90503 . Telephone: 800-447-9826. Web site:

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