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The "Unwich" of Masterkeying: No PINS!

Is it possible to master keys without master pins? The topic doesn't get enough attention because our focus when it comes to master keying is about computer programs, pinning charts, and cross keying. But there is a powerful and helpful section that you know already that gets left out. If you are familiar with a key blank directory, a book that you look up different keyway profiles to help you identify keys, the concept is in there, called Multiplex Key Systems. And using this concept, you can make one key bitting with zero master pins, two different change keys, and a master key.

 key blank directory


 key blank directory tree

What you're looking at is a page out of the Ilco key blank directory, a Schlage. At the bottom, you'll see the SC19 and SC20 key, the Schlage L keyway, and the lines that go up to represent the keyways it fits in. So, the L keyway is going to fit in the H, the J and the K, or the H, J, the K is going to work in that whole top line of keys, the C, the CE, E, EF, F, FG, and G. But remember that the key tree only works up, it does not work down, and that's why you can use it to your advantage when you need to.


For Door A, we're going to pin up an SC4 cylinder, Schlage C. For Office Store B, we will pin up an E cylinder to SC9, and H key, the SC15, as the master key.

We're going to use the same key bitting for all three of them, and we're going to create a mini Master Key System. 

schlage key directory sheet


I already have all the keys cut and the cylinders pinned. All three keys are cut precisely to the same key bitting, but the keyways are different.

 3 cut keys

Next is to test the key to the cylinder. I started with SC4 and then labeled the cylinder with A, then the E keyway to the SC9 key, and labeled B.

 key the cylinder

But if we try to use the SC4 key to cylinder B, it won't go in. Same with SC9 to cylinder A.

 key cylinder

 key and cylinder

According to the chart here, the only key that's going to work in these two locks is the H keyway, the SC15. It's going to go into both of them, and that's what makes this so unique. 

 masterkeying tips

 how to masterkey


Alright, so there you have it. That's some pretty powerful stuff right there. Now, of course, you never want to use master key bitting the same as a change key bitting. You don't want to do that. I did it to prove how powerful this concept can be in the real world. And I want to make sure that you can take this information, put it in your back pocket and deploy it when the time is right, when the circumstances are right in the real world, right? You can use this on different properties, maybe you have to start over a whole brand new system, and that customer has to use their existing master key but wants to make sure they're not going to have cross keying in the future. Right? Well, you can easily step that master key up to the H keyway, and then you could switch all the new cylinders over to the E keyway instead of the C. So as you rework to redo the system, you won't have to worry about the old tenant keys or the new tenant keys working into each other because, well, the key is won't even fit in, right? There's a lot of significant situations that you can use this for. But I'd love to know, did you already know this information, or is this a lightbulb moment for you? Please let me know in the comments below. Thank you, and we'll see you next time.

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