Master Key

Why Master Key

Master key is the given name to a previously set up key in a determinated number of locks in which each user is going to have their unique key combination and the master key is intentionally fixed to work in all the locks. It could be any precut key, all the locks have to be compatibles(same key way).
Depending on the label of clearance that the user is going to have you could set up a Grand Master key and a Master key
To set up Two or more keys in one lock you have to decode your keys first to find out each key combination, with the proper gauge tool you will read the cuts on your keys starting from the shoulder to the tip and write this down as if you were going to add this numbers. For Example:

From Shoulder to tip:  #1 cut,  #2 cut,  #3 cut,  #4 cut,  #5 cut

key #1:    5,   6,   1,   8,   3

key #2:    3,   8,   5,   1,   5

key #3:    7,   3,   6,   6,   8

Bottom Pins:    3,   3,   1,   1,   3

Master pins:    2,   3,   4,   5,   2    First set

Master pins:    2,   2,   1,   2,   3    Second set

Key Decoder

Key

If you want to set up eny of this key combinations into a lock all you do it is load in a #1 pin were there is a #1 cut on the key, #2 pin were there is a #2 cut on the key and so on.

Pinning Kit

Bottom pins

Now if you want more than one key combination to work the lock we have to use botton pins and master pins; witch are the ones we are going to be loading in the plug, there is also the top pins bud those will remain on the housing of the lock with the springs.

Top Pins

To determine which ones are going to be your botton pins you compare all the depth corresponding to the #1 cuts off the keys to be set up and always take the smaller number; that one is going to be the first botton pin then you do the same for the remaining cuts. If you refair to the example you can see that the first cut on my keys were depth 5 on key#1 cut#1, depth 3 on key#2 cut#1 and depth 7 on key#3 cut#1 the correct botton pin to load on the first chamber of the plug will be a number 3 pin.

Ones you have determined your bottons pins it is time to load the master pins. If you were going to set up only Key#1 combination and Key#2 combination to the lock you go back to position number one or #1 cut the smaller number it's your botton pin sustract that from the remainnig number and the result it is going to be your master pin. From the example: depth 3 on key#2 cut#1 a number 3 pin is your botton pin sustract that from depth 5 on key#1 cut#1; 5-3=2 and a number 2 master pin has to be use on top of the botton pin for the key to be able to work the lock.

Master Pins

 If you want to set up 3 keys combinations on the lock after you have your botton pins go back to position number one or #1 cut the smaller number it's your botton pin sustract that from the smaller of the two remainnig numbers and the result it is going to be your first master pin, the sustraction from the higher numbers on that position is going to be your second master pin.

 From the example: depth 3 on key#2 cut#1 a number 3 pin is your botton pin sustract that from depth 5 on key#1 cut#1; 5-3=2 and a number 2 master pin has to be use on top of the botton pin, depth 7 and 5 on key#3 cut#1 and key#1 cut#1 are the higher numbers sustract that; 7-5=2 and a number 2 master pin has to be use on top of the number 2 master pin previously loaded for the 3 keys to work the lock. Do the same for the remainning cuts and try your keys.

When working with a large amount of locks you can help yourself with a Master Keying Software. This speeds up and simplifies each keying procedure.

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Automotive and Commercial Locksmith

6105 Johnson Street

Hollywood, FL 33024

Phone: 1.954.347.9566

Website: AutomotiveAndCommercialLocksmith.com