Master Key Systems give you complete flexibility
Hi all, having two keys that look different but both can fit the same lock is not something magical and can be explained quite easily and is the way Master Keys Systems work. It is best perhaps to have a look at the video attached below and it is far easier to show you as opposed to explaining in writing.
Below the video is the transcript of the video
Please enjoy but off course should you need more information or advise, pop an email over at any time email@example.com
Head of the tech department
TRUST Security - Trust LocksOnline
Hi and welcome to locksonline.co.uk. Today we're going to have a look at
some master key systems and what are the basic principles of the master key
system? How do master key systems work?
We get a lot of people phoning us up, emailing us, looking on understanding
what master key systems are about, asking questions about how do they work
and how do we suite them and how is it all divided and so forth. Trying to
fully understand how two different styles of keys would fit in the same
lock and operate the door. So, we'll do a little bit of math at the moment,
just to explain to you roughly how the master key systems work in general,
for the Yale type cylinder locks.
What you have inside a cylinder are what we call pins. What you normally
have is you have a housing pin, which is what we call what sits in the
housing. There's a little spring that sits on top of here. Then, we'll have
what we call in the trade then, a plug pin. That sits there like that. Now,
that position there between the two is what we call in the trade the shear
line. The idea is, is when you put the key in, this gets pushed up, so
therefore then, the cut in the key will denote where this sits on the shear
So, in an example here, we could have the shear line - get rid of that line
in a second - if the key wasn't in the lock, the shear line could be there
for an example. But then when you push the key in, this pushes the pin up,
and consequently that shear line then meets this position here and allows
then the key to turn. So, that's the basic principle of how a cylinder
Now, all these pins - obviously, there are going to be six or seven of
them, or five of them all in a row, but this is one particular pin - the
principle is the same then with all the different pins. But let's assume,
for the principles of this exercise, that this pin has a number of ten, and
the key that we would fit into the cylinder would have a cut in it, of also
that has a depth of ten. So, therefore then, that depth fits that pin. It's
simple as that really.
But if we were to have another key that was five, let's say a little bit
shallower... Let me just rub this out a second. I'll say five. Let me just
clean that up a little bit. So, it would be a little bit shallower. Say,
there like that and that's five, and then that there, then, is our ten.
Okay? What you will find is the five won't go into that, and it won't lift
that pin too high, and therefore not sit on the shear line.
So, what we can do is we could split this pin in two. What we can do then
is put in a five, and also what we call a master pin five, so we would get
rid of the ten. Now, what you see is you will see a five and also a ten by
adding the two together. So, therefore then, different keys with a cut of
ten, and a key with a cut of five would both operate that particular pin in
Now, when you take that over multiple pins all the way through your
cylinder, then you will see how the cuts then perform to a master key
system and master key cylinders. So, that's the basic principles. There are
lots of different principles, lots of different concepts, lots of different
ideas, but it's all to do with matrices. Probably when you were in school
or when I was in school, we had learned a little bit about matrices, and
this is what master key systems are all about.
So, anyway, I've cleared that off now, because then we need to have a look
at the hierarchy of master key systems, and how they work in principle. One
of the easiest ways to understand how master key systems work is to look
at, say for an example, an office block, and the management structure
within a business.
So, what you would normally have is you would have what we would call the
grand master key, and we normally call that a GMK. It's pretty common to
have the grand master key called the GMK. That quite probably, let's say
that's the boss of this business, whatever the business is, and he's the
boss. The grand master key would allow you to go through loads and loads of
different locks and doors and so forth throughout the whole building.
Because you are the boss, you carry the grand master key. That gives you
privileges throughout the whole of your building.
But then you might have your building split into subdivisions or floors, or
different management or so forth. Or, for an example, you could turn around
and say, "Well, okay. I want to subdivide each floor into a subsection. So,
what you'll find is, is we can then create the tree going down into, say,
those three subsections. These would be called then, masters.
For the same of this exercise, we will call this Master A, and we will call
this then Master B, and then we'll call this one also, then, Master C. Now,
for this particular principle, this could be the ground floor, this could
be the first floor, and this could be the second floor.
Anybody who carries this key has access to all the offices on the ground
floor. Anybody who has access to this key similarly, on the first floor and
again on the second floor, but on the ground floor we can split it even
further and we could say, well, on the ground floor there are three areas.
We could turn around and say that there's advertising, there's marketing,
and then there's, say, finance.
So, then we can break that down again into three subgroups. So this one
then would be AA, being the Master A, sub A. This would be, say, AB, and
this would be AC. This would be, let's call it Admin. This is called
Finance - we'll call FI Finance - and then let's call this, Accounts. There
they are there. Now, what you will find is the manager or the foreman,
whoever who's the head of administration would have one key that would fit
all the offices in the Admin, similar in the Finance, and similar in
So in the Accounts department, let's use an example, we have five offices -
one, two, three, four, five. Let's say, for the sake of this exercise, that
I, myself, personally, work in this office, here, number five. So I would
be given the key to my office. But the head of the Accounts department
would have a key that would fit all of these offices. The manager for the
floor would have a key that would fit Admin, Finance, and the Accounts.
Then the big boss up here would have a key that would fit it all.
Now similarly, then you could go on and you could say, "Well, this could be
the first floor and in the first floor there's mechanics, or
administration," or something else and you could carry on this tree all the
way out. A typical master key system would eventually - or the ones that we
can build for you - would normally take up to in excess of 1,000 differs.
We call the doors, the individuals keys, we call those differs, and all of
these here, we call them grand masters, masters, sub-masters, and then
these are the differs. There's nothing stopping you then have, say, two
doors on the same key, because there could be a back door, a front door,
and a side door to an office. So, that's the matrix. That's how the plan of
a master key system works.
I hope that spending this couple of minutes with you has explained, and
hopefully haven't confused you too much and you can understand the matrix
and how it all works. So, when you speak to our guys on the sales, or
you're not 100% sure, feel free to give me a call. My name is Darrel and
I'm head of the tech team. I can explain this to you with a video.
But if you were to consider it like that, that gives you some sort of an
idea. I'm going to extend it a little bit further. I know time is of the
essence, but I want to explain it to you in a different way for that of a
hotel. Because we do get a lot of people here who have got small little
hotels, and so forth that perhaps want to have a master key system, wants
to give the professional look, but the customer only ever has to have one
So, this is how the master key system would work for a hotel. Again, we
would have the GMK key, GMK because the board is a bit wet now. What we
would do is we would split that into two groups. We'd split it into the
rooms and perhaps we would then split this into private. So, this is the
private area for the owner. This is the GMK up here. It's drying up a bit
for us now, and these are rooms.
Then, what we would have then is, say, for an example, there could be ten
rooms. These are our differs, okay? So, that would be room one, room two,
room three, room four, room five, room six, room seven, room eight. Rooms
key, which would be a sub-key, that could perhaps be the cleaner's key. So,
when the cleaner comes in to work, she picks up her sub-key that allows her
into this group of rooms to clean.
But when you want to give these room keys out to people, what you'll
probably find is on certain hotels you've got one key. But they not only
fit to each individual room, but they'll also fit the front door. In a
master key system, we would treat that as being a common cylinder, common.
We can pin that up to be common to however many locks there are in a suite.
It can be common to one particular door. It can be common to multiple
doors. You may find you'll have to go through two or three doors with your
key before you actually get to your room. What we would do then is pin them
all up key to like to common.
So, that's how, perhaps, a master key system may work in a smaller hotel or
in a bed and breakfast or a guest house, etc. and that's the basic
principles of that. Again, we design and build our master key systems to
suit you and not the other way around. Many thanks for your time, I really
appreciate it. Like I said, if you're still not 100% sure, you can contact
me on firstname.lastname@example.org and I can explain all that to you as well.
Thank you very much for listening and watching.