Retrofiting Knob to Lever Locks Made Easy

Use A1 Security Manufacturing’s BUL-3 retrofit jig for bored lever locks


To help identify a lock, look at the latch faceplate to find the name of the lock company. Some lock companies private label a different lock manufacturer product. The name on the latch faceplate can be either company that manufactured the lock or the company that private labeled the lock.

Our chart, available online with this article, lists the more common lock manufacturers whose lever equipped cylindrical and tubular locks are equipped with external through bolting. Not all through bolt holes in all locks can be drilled using the BUL-3 Retrofit Jig.

Some holes are in the 6 and 12 o’clock positions are a few thousands off from 2-3/4”. This can include 2-5/8”. To resolve this problem using the A1 BUL-3, some locksmiths will drill the 5/16” hole, remove the jig and redrill the opening using a larger diameter bit, usually a 3/8” diameter. For a lock equipped with a 2-5/8” distance, drilling two 3/8” diameter holes provide the extra 1/8” to accommodate the two through bolts.

The use of a retrofit jig simplifies the task by properly locating the through bolt holes.

Important: Always wear eye protection and follow all safety rules when operating electrical equipment.

For more information on any of the installation tools in this article, contact your local locksmith distributor or A1 Security Mfg. Telephone: 877-725-2121. Web Site: www.demanda1.com.

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