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Existing Master Key Systems? You have 3 options! (really 4) | Locksmithing 101

Taking over existing master key systems is practically unavoidable. It's going to happen if you're in the lock and key industry, but the question is, what the right way to handle it? That's what we're going to be exploring.

Taking over existing master key systems is part of the job. Going to an appointment with a big Master Key System and the customer will ask you to work on one door. You'll be like, 'Well, I can't work on that door without seeing the master keying chart.' or maybe they want you to start to remaster key in it, but they don't want to do it all at once. On top of that, you don't even know the chart, the situations that have led up to that problem, what it looks like, and it can be not very comforting. It can be frustrating and expensive for your customer.



You don't want to pick some old random change key, take their master key, and pin-up the lock. Don't ever do it; it's not a good idea. Instead of causing all sorts of issues, some of which could be security-related, you don't want to go there. It can be tempting, I get it, you're in a hurry, but do not do it ever, make that rule for yourself. Please don't do it.



What options do you have when you encounter this situation?

OPTION #1 - GET THE CHART. If you can hunt down the original Master Key System chart and the person who did it before you did an excellent job keeping all the records, you can get it figured out straightforwardly and start adding on or servicing the system. However, the truth is, the number of times that's going to happen while you're going to build an account, on the one hand, your entire career, that's not something that happens often.

OPTION #2 - START OVER. Completely changing the Master Key System on the entire building can be a chore; it can be very time-consuming. If this is the option that your customer wants to do, and you want to do, you didn't plan on it to get it done the same. So, it will be expensive; that's the biggest downside. If there are many doors, maybe there are 100 or 200 doors on the system, that will be very expensive. And who knows, that might not even fit into your customer's budget.

OPTION #3 - INTRODUCE USING A MULTIPLEX KEY SYSTEM. Now, if you don't know what I'm talking about, check the link in the notes below. Using the multiplex key systems will check a couple of boxes that you and your customer most likely will like. Let's say the system you show up to on a Schlage C keyway on SC4. Very common in the commercial lock industry. And since you don't have the chart, the customer cannot go to the expense right now of remasterkeying the entire building or complex. You can start switching the cylinders over to the Schlage E keyway because that way, the ones that are existing in use are still working fine and don't have any issues. You're going to let those keep going until they can get the whole system switched over budget-wise or as needed. Since they're using the Schlage C keyway, now if you look at this chart quick, you can see the Schlage C keyway, and then two keyways over, you can see the Schlage E keyway, which is going to be the SC nine for the six pins. But all the new stuff you're doing will be on an entirely different keyway. That way, you don't have to worry about the system's integrity because the E keys aren't going to fit into the C, and the C isn't going to fit into the E, and you can go as needed.


But then you have to remember if the customer wants to use their existing master key. That's no problem. All you have to do is look at the chart again, reduplicate the customer's master key from Schlage C to Schlage H keyway, which is the SC15 key. Alright, and so now that the SC15 key is still going to work in all of the existing Schlage C keyway, Locks, and Master Key Systems, it's also going to be working in your new Schlage E system.


We're going to have two different keyways, the Schlage C is old, Schlage E is new, and they're going to go to work together for a time because the keys will work in each other's locks. But as a matter of fact, they're not even going to go in, and that's a potent tool. That's going to help you and help your customer achieve what they're looking for.


Then as time goes on, as you continue to replace the cylinders, you're going to know they get everything on the Schlage E. The customer will be super happy that you worked at the pace that they needed to be, and you're going to have a good system with integrity.


PROBLEM: Maybe there's an office supply closet that they need to get to, and if you switch it to E keyway, well, the people with Schlage C can't get in and vice versa.

ANSWER: All you have to do is use a composite keyway on that door. Use the Schlage C-K cylinder; that way, both keys, the E and the C, will be able to slide in and work. I recommend as time goes on and all the Schlage C's are done because you've replaced them all with E, go ahead and swap that cylinder out to each Schlage E and keep the integrity of the system to the highest level that you can.

I hope that you found this helpful, and it gives you another option you can think about when dealing with existing master key systems. I would love to know your thoughts in the comments below and make sure to include the #LockBoss to automatically get entered in to win one of five free prizes we give away every Tuesday on YouTube. Thank you, and we'll see you next time.

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