Lesson 6: Master Key Systems- Part 3

Master Keying the Cylinder

Dismantling the core:

      1. Remove the end-cap using the end-cap remover. The tailpiece slides into the hollow core of the end-cap remover. Align the grooves of the end cap with the grooves on the end-cap remover, and rotate counter clockwise. *If you do not have an end-cap remover, you can remove the end cap by depressing the set pin with a pokey device while rotating the end-cap with your fingers.
      2. Extract the set pin and set spring.
      3. Insert the pre-existing key and turn 45-90 degrees.
      4. Press the follower against the back side of the core. Slowly insert the follower into the back of the cylinder, removing the core as you do so. This will keep the top pins and springs from exploding out of the cylinder as you remove the core.
      5. check the top chamber for pre-existing master pins. Slide the up the cylinder, applying pressure to the top pins with your tweezers. Slowly release pressure on the top pins, allowing the pin to protrude out of the chamber. If there are master pins, they will appear as thin disks laying on the surface of the top pins. Remove them.

Rekey the cylinder:

      1. Empty the pins that remain in the cylinder core. These can be disposed of or placed into a loose pins section of your pin kit
      2. Using the chart you built for your master key system, replace the pins according to the depth of the new codes. Start with the bottom pins and layer the master pins on top of them. Check the normal key and the master key to make sure they will work. The pins should create separate sheer lines when each key is inserted.


      1. Slide the core back into the cylinder at a 45-90 degree angle. With your thumb over the keyway, check the accuracy of your pinning by spinning each of the keys back and forth a few times. Test some of the other keys from your master key system to ensure that there is no accidental cross keying. If the cylinder feels tight or stiff it is possible that one or more of the pins is a little to big. If the cylinder is catching, your pins need to be readjusted accordingly.
      2. With your thumb over the keyway, extract the key and reassemble the set spring, set pin, c-clip, tailpiece and end-cap. Thread the end-cap back onto the cylinder so that it is snug but not to tight. If the end-cap is on to tight the cylinder will feel stiff and may jam shut. If the end-cap is not on tight enough the key may get stuck in the keyway or you may have difficulty removing the key from the cylinder. If this occurs you can remove the key by holding the core with your thumb as you extract the key.
      3. Check each of the keys again. The cylinder should spin smoothly and with little resistance. At this time you should check the old keys to ensure that they no longer work.
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