How where you taught masterkeying?

[chieflittlehorse]

From what I learned in school and working for different locksmith companies, it seems like the rules of masterkeying has changed.

Some say the numbers in the MK bitting should not show up in any of the change keys. Which means there shall be a master pin in each chamber.

Some prefer use a shallow MK bitting for easier pinning and apply the above rule with it.

Just what are your thoughts on masterkeying and how do you masterkey your locks?

I myself will choose a random number and only progress enought chambers for what I need or for expansion, and a particular number in the MK will show up on some change keys on the way I do it.

Just trying to pick your brains on the subject....

Clh...

[DIY Dave]

I was taught that you really only need to have one cut to be different thus only having one chamber master pinned (for a small system anyhow) . It makes it more difficult to pick and less likely it will be cross keyed with other keys.

Although it is possible to pin that way, you should avoid using pass keys that have only a 1 difference (if someone's key is worn down you don't want it working other people's locks) Also, I never use 1 master pins in kwikset, they are too small and once the pin wears down a little it could come out of the chamber and jam up the lock leaving you responsible to fix it.

Example
master 14356
pass 1 14352
pass 2 14354
pass 3 14358
pass 4 14350
don't use 14351 because it's only one cut different then pass key 4
Any more than that you will need more chambers rotating.
Just my $.02 hope it helps

[Master Keying]

Some say the numbers in the MK bitting should not show up in any of the change keys

Incorrect. There is a "Rotating Method" which actually uses a MK bitting and it "rotates" through the bitting.

Some prefer use a shallow MK bitting for easier pinning and apply the above rule with it.

I use mix of both - shallow and deep.

Just what are your thoughts on masterkeying and how do you masterkey your locks?

It depends on project and product you want to use, and the structure and complexity of the system.

I myself will choose a random number...

Random number - that's a good start then follow the rest of rules.

...and only progress enought chambers for what I need or for expansion,...

You have to progress enough chambers for what you need AND for expansion, which usually is 50%.

...and a particular number in the MK will show up on some change keys on the way I do it.

So do you use "Rotating Method"?

you should avoid using pass keys that have only a 1 difference

You can use it, there isn't problem using a 1 cut difference.

Example
master 14356
pass 1 14352
pass 2 14354
pass 3 14358
pass 4 14350
don't use 14351 because it's only one cut different then pass key 4

I know this is an example, but... it is wrong example, sorry.
A believe that "0 - zero" in your example is the smallest pin - shallow bitting/cut, therefore....
You should never - ever use a bitting /cuts lower than your MK bitting is !! As the change key can be re-cut to MK bitting.

So, from the example above the MK should be 14350 and the last 5th chamber is progressed. If the system is just KD (Key to Differ) then you can get 4 or 8 CK depends of the product you using. You can get away with 1 cut difference as the pinning wont use 1 master pin.
Again. It depends of the product you using as some have very big tolerance and even 2 steps cut difference may open and cause you a problem.

MK - Master Key
CK- Change Key
KD - Key to Differ
Progression - Combination

[mastersmith]

I was taught never to mix odd/even depths in the same pin chamber. So if the first chamber is a 4 cut for the master key, the only cuts used there will be even numbers. IE>0,2,6,8.etc. depending on the system used. This is parity, and parity is always maintained when writing your system. There is no possibility of using a 1 master wafer as all cuts are at least 2 numbers apart. If my master is 403651 then all keys in the system are chosen with the criteria of even/even/odd/even/odd/odd. And by the way, I have never written a system so large that I needed to use cuts from the master in a change key. I work with those systems every day, but I didn't write them.

[Master Keying]

I was taught never to mix odd/even depths in the same pin chamber

True and correct.
But, in depends on a size of the project and product you HAVE to use.

I previously wrote...

If the system is just KD (Key to Differ) then you can get 4 or 8 CK depends of the product you using. You can get away with 1 cut difference as the pinning wont use 1 master pin.

I'm gonna use bitting/cuts 14350 for my Master Key and will progress last chamber (5th) with Change Keys / Pass Keys.
Here is an example 1:
I'll get 4 combinations with "depth step" 2 and even bitting for my CK / Pass keys;

MK. - 14350
CK1 - 14352
CK2 - 14354
CK3 - 14356
CK4 - 14358

The pinning for CK1;
BP - 14350
MP - xxxx2

The pinning for CK2;
BP - 14350
MP - xxxx4

The pinning for CK3;
BP - 14350
MP - xxxx6

The pinning for CK4;
BP - 14350
MP - xxxx8

-----------------------------------------------------------------
Here is an example 2:
I'll get 8 combinations with a "depth step" 1 bitting for my CK / Pass keys is;

MK. - 14350
CK1 - 14352
CKA - 14353
CK2 - 14354
CKB - 14355
CK3 - 14356
CKC - 14357
CK4 - 14358
CKD - 14359

The pinning for CK1, CK2, CK3 and CK4 will be the same as in example 1.
And pinning for CKA, CKB, CKC and CKD will be;

The pinning for CKA;
BP - 14350
MP - xxxx3

The pinning for CKB;
BP - 14350
MP - xxxx5

The pinning for CKC;
BP - 14350
MP - xxxx7

The pinning for CKD;
BP - 14350
MP - xxxx9


BP - Bottom Pin
MP - Master Pin
x - No Master Pin

As you can see, there are no 1 master pins, and there would be no cross-keying between keys.
Again, if you going to build it with some cheap-big-tolerance product, then you might have a problem, but that is the cost you have to pay when getting a cheap product.

Just for fun, do you know how many (hypothetically usable) KD combinations you have on 5 pin cylinder?

[DIY Dave]

you should avoid using pass keys that have only a 1 difference

You can use it, there isn't problem using a 1 cut difference.

Example
master 14356
pass 1 14352
pass 2 14354
pass 3 14358
pass 4 14350
don't use 14351 because it's only one cut different then pass key 4

I know this is an example, but... it is wrong example, sorry.
A believe that "0 - zero" in your example is the smallest pin - shallow bitting/cut, therefore....
You should never - ever use a bitting /cuts lower than your MK bitting is !! As the change key can be re-cut to MK bitting.

One differences can often be a problem. Yesterday I was rekeying a lock and accidently placed a 5 pin in instead of a 6 and the key still worked, it was a little rough but it still worked. If you used one differences for you pass keys you could end up with a huge cross-keyed mess. Never use cuts on pass keys with cuts shallower than the master? On a large key system you would end up giving them a bump key for their master. If someone wants a master key bad enough they could just go get a blank and file it down just as easy as turning their key into a master.

[Master Keying]

Never use cuts on pass keys with cuts shallower than the master?

You should never - ever use a bitting /cuts lower than your MK bitting is !! As the change key can be re-cut to MK bitting.

Thanks for pointing this out. I might start explaining myself more clearer.
Although, it was explained in the second sentence, it should read HIGHER cuts.

One differences can often be a problem.Yesterday I was rekeying a lock and accidently placed a 5 pin in instead of a 6 and the key still worked, it was a little rough but it still worked. If you used one differences for you pass keys you could end up with a huge cross-keyed mess.

Thats why I wrote previously this;

if you going to build it with some cheap-big-tolerance product, then you might have a problem, but that is the cost you have to pay when getting a cheap product.

If someone wants a master key bad enough they could just go get a blank and file it down just as easy as turning their key into a master.

Yes and No.
To get a blank key, thats an extra effort. Also, if the key is restricted profile +extra effort.
But if you use an existing key from existing system, its easy to re-cut the CK / Pass key into a master...

[DIY Dave]

if you going to build it with some cheap-big-tolerance product, then you might have a problem, but that is the cost you have to pay when getting a cheap product.

If someone wants a master key bad enough they could just go get a blank and file it down just as easy as turning their key into a master.

Yes and No.
To get a blank key, thats an extra effort. Also, if the key is restricted profile +extra effort.
But if you use an existing key from existing system, its easy to re-cut the CK / Pass key into a master...

I didn't mean to start an argument, just wanted to clear some things up. It wasn't really a cheap product, it was a high end master padlock...I guess they kind of suck. Good point on the restricted keys. I guess it would be pretty easy for someone to take a lock apart and find the master keyed chamber and file down their operating key, I hadn't thought of that. I was thinking they would have to get dups of their key made and file down one cut on each one to try and make a master out of one of them. They would still have to know about how locks work though in order to find the master keyed chamber. Good discussion

[Master Keying]

I didn't mean to start an argument, just wanted to clear some things up.

No arguing here just healthy discussion.

it was a high end master padlock...I guess they kind of suck.

High end would not have this problem.

I guess it would be pretty easy for someone to take a lock apart and find the master keyed chamber and file down their operating key

Some locks/cylinders cannot be removed from door if you dont have a key, some can be.
To find out MK from pinning is not hard, but also its not easy. It takes "some" skill and resources. I might mentioned previously, that if use for your MK bitting / cuts one cut deepest and one shallow - (for ex. 1 and 9) its bit harder to find, but possible and it varies from system to system. You would need few keys and few cylinders. (Do not use 1 and 9 next to each other !! The difference shold not be more the 6, but it depends on a product.)
Also, when rekeying old cylinders to MK system, do not use old pins. Use new bottom pins, Top pins and even new springs. It make a BIG difference then the old ones.