Reverse Engineer Control Key

  • $120-150 Trip charge to come out to your location
  • $20-150 to derive the control or key from a designated core which includes the cost of removing it from its housing but doesn’t include the cost of replacement core or housing if destructive removal was required
  • This can be done for any SFIC, LFIC or FSIC keyway that isn’t restricted including Best, Sargent, Corbin Russwin and others
  • I don’t guarantee this key will work on all of your cores because the cores could have been altered or damaged by high use or other locksmiths may have changed the control or master key bitting without your knowledge

You’re probably here because you want to change the key used in a lock that somebody told you is an interchangeable or removable core. You’re at the right place. I can regenerate or derive the control key from your lock though I might require evidence that you own the lock in question or manage the building.

The control key is a special key whose sole purpose is to insert or remove cores from their housing. It doesn’t operate the lock. That is to say, it cannot be used to open any doors. It may be marked “C” or “Control” or it may be blank. You will know it is a control key if when turned in the lock it only rotates ten or fifteen degrees. You may have accidentally pulled the core out after turning the key.

Deriving the control key normally requires that the core be removed from the lock first. This requires either drilling the core in a special place or using lockpicks. Then it’s time for the math because these locks all adhere to certain rules for how they are prepared.

Once the control key is made it will probably work on all the other cores but there is a chance that it won’t, especially in apartment buildings or restaurants where the manager has a “just get it done” attitude and numerous locksmiths have come in to unlock and rekey various doors. I recently rekeyed a large apartment building that was only a few years old at that point because the masterkey was stolen and in that short amount of time at least twenty of the units had replaced cores that worked with an unknown control key. One of the units had a drilled core that enabled anybody to open the door! A few were missing the original hardware which necessitated replacement deadbolts increasing the cost. This substantially increased the cost of rekeying. If the same control key worked everywhere it would have taken eight hours less and would have saved the owner over $1000.

Once you have the control key you may want to know about high security cores I offer that prevent the need for rekeying since the keys are restricted and can’t be copied anywhere without your authorization.