First, we need to have a conversation with the customer about DND keys. Stamping an ordinary unrestricted key “DO NOT DUPLICATE” is deceptive because it gives a false sense of security. If they really want key control with keys that can’t easily be copied, they need restricted keys. That gen- erally means upgrading from residential five-pin locks to commercial-grade six-pin, which will accommodate restricted cylin- ders. Even if they don’t really need key con- trol, upgrading is still a good idea. Fewer people carry six-pin keys, so there’s less risk of external key interchange. And six pins could allow us to get more change keys or an extra constant. We might convince the owners to spend the money by pointing out that this is an opportunity to upgrade from knobs to levers to meet ADA stan- dards. In any case, we really want to have this conversation before all the locks have been pinned, while it’s not too late to do something about it. A Better Solution Now consider system design. We might suggest a rotating constant system with just two progressed chambers and all the others constant. With two-step progres- sion, four constants and two progressed chambers gives us 15 ways to rearrange the constants, each of which provides up to 16 change keys. That’s 240 keys — enough to rekey each unit eight times (minus MACS violations, of course). That should be enough to last for a couple de- cades. And we’d only need two master pins per lock, which is about half what they have now. That would be a huge im- provement; it cuts the total number of incidental keys by about a factor of four. But I have an even better suggestion. Let’s single-key each apartment, with no master pins in any of the locks. To reassure the owners of the building, we put one copy of each key into a key box in the basement, secured with a lock of a WWW.ALOA.ORG Figure 1. Unfortunately, shoeboxing uses more master pins than necessary, and it relies on luck to avoid key interchange. different brand, such as Medeco. Who- ever carries that Medeco key can access any apartment at any time, for emergen- cies. They just go to the basement, unlock the box, and take the appropriate key off the hook. Even better, secure the key box with an electronic lock that has an audit trail. Give a different access code for each person who would otherwise carry a mas- ter key. That way, there’s a record of who accessed the box and when they did it. The beauty of this solution is that we’ve eliminated the two major problems as- sociated with master keying residences. First, we’ve eliminated the risk of ten- ants decoding their own locks to reverse engineer the master key. The locks won’t contain any information about the master key at all. Second, we’ve kept the physi- cal security of the locks themselves in- tact; they would be no more vulnerable to picking or bumping than any other single-keyed lock. This is a great option, especially if we can’t convince them to upgrade the hardware. But here’s one more issue to address: There is a gate at the back of the building. Tenants use the gate to get to and from the side street. But some other people, who don’t even live there, have been using that gate as a shortcut. The owners wanted to discourage non-residents from using the gate, so they put a lock on the gate and pinned it to operate with all the tenants’ keys. This is known as “maison keying.” Now we understand why they said the lock keeps jamming. It has stacks of #1 master pins in every chamber. Within a week, the lock was jammed, so residents started propping the gate open, which defeats the purpose of having the gate at all. Is there a way we can we accommodate this request? And can we do it without us- ing master pins? I’ll give you my answer in part two of this article series. I’ll also show you an example of selective master keying, which allows us to create small master key systems with hardly any master pins. Ralph Forrest-Ball was a math teacher for 12 years before becoming a full-time locksmith. He joined ALOA in 1997 and earned the CML credential in 2009. From 2009 to 2019, he was the owner of Emerald City Locksmith in Eugene, OR, and he was the winner of ALOA’s Best Shop contest in 2011. He currently works part-time as a locksmith in Corvallis, OR. JANUARY 2022 KEYNOTES 43
