Master Keying Questions

[btshaw]

Guys,
thanks to all of you - these are very helpful guidelines. One area I'm still unclear on:

should you try to minimize the number of master pins or should should you try to make sure the TMK and the change keys have no cuts in common? I've seen "rules" for both approaches with justifications, but it is hard for me to gauge the real world right approach and why.

It seems to me that for my simple 3 level system, I could progress one chamber to get my MK's and then simply progress another chamber to get all my change keys. Is this flawed logic?

Will a computer-generated system just be a TP or RC chart or would it take into account the system requirements above?

thanks.
bt

[jeffmoss26]

Some good info in this thread!

[Sinifar]

Master keying is the controlled destruction of the security of a lock.

Having said that - every master pin segment put into a lock reduces the security of it and increases the number of possible phantom keys. therefore, try to have as few master pins in the cylinder as possible to do your job.

Phantom keys are keys which work your system, and are not intended to do so. They maybe keys just off your key ring, or somebody elses. A major nightmare.

For example - Schlage reserves 0 - 1 - 2 for master work only. So putting one of those in a pin set alone, as a "ward" pin, or constant will ensure that every key out there will not interchange, or be a phantom key which would work in your locks.

In fact the more pins in common, the more secure you are. For example, MK - 542123, 1 - 544763, 2- 540583 -- the common or constant 54xxx3 insures you that no key except those with those cuts in those positions will work in your system. By having cuts above and below the master, you do not expose the master by having it all the "high cuts" -- 0 - 1 - 2- 3, or all low cuts, 6 - 7 - 8 - 9. The xxx is the rotating change key pins.

Forget the "level" thing. Levels are for talking about only. Use the most direct and simplest methods to get the work done. IF you try - you can key things in groups, say, the plant department, the tool department, marketing, and / or sales. Each would be a separate change key. This way if you needed a key for say the boss of the area, it can be done with a simple hat trick. ie - M - 542123, 6AA - 544763. This would give you that department's keying, now for the boss's office - SM1 - 6 to designate the first submaster, of key 6 - 542763. This would give you the key to fit the boss's office, without exposing the master - and his key would work all the other locks, but their's would not work back. Just key his first few to the 5 - 4 - 2 then the rest. Simple and direct. This is also one of the phantom keys which I talked to earlier.

If you want levels, there are "Master mills" - keys which can go into other keyways. Schlage has Classic "C" - "CE" - "E", and these are bypassed by "H". So if you want to really jazz it up, you key one section in "C" - and one in "E", and using the same master work for both, the keyway being the difference, and then "H" becomes a grand master without any work at all. Just cut the same master for each section into "H" and you are done. You just created a grand master.

As far as how many change keys? In a six pin system you can get over 4000 usable combinations without violating any of the MACS or other rules. Again, don't wafer the thing up. One master can run this whole thing - although you may want to issue master keys for each building, or a series of buildings, in that case some work is needed.

In this example, we are going to key up a nursing home. There are four sections to it, and they want a master for each. There are about 75 rooms in each section. SO - GM - 2xxxx2, Master A - 4xxxx8, Master B - 6xxxx4 Master C-0xxxx6, and Master D- 8xxxx0. The xxxx is the rotating pins for the individual combinations. Just make sure your selection for this job does not exceed the MACS, and you are home. Each key in the system for each section would have a constant of the numbers, shown with the xxxx being the actual key for that room

Next - you don't want 1AA, 1BB, 1CC, and 1DD to "repeat" - you are going to use the same pin work for each section. So for AA, just use the pin work as printed off the sheet. For BB, reverse the sheet and work from the bottom up. For the next section, fold the system in half, and then repeat again, from the top down for CC, and the bottom up for DD. This gives a different "look" to each key, and nobody is wiser for what you did. It works. We just shipped this job out.

This also gives you room to work - expand, revise, or add unexpected sections. you have more combinations available then you used, so your "spares" become a life saver. Never pin so tight that you are in a corner and have to open something up, which may lead to a cross key. Plan your system ahead, and plan on changes. Additional master sections could be - Master E - 6xxxx0, Master F - 4xxxx6 and so on. So here you have a multi-level system which just keeps on expanding without any big sweat on your part.

IF you did this right, you used in the example, 75 keys, so on a printout of 120 keys, you are really getting a wide, non repeating system.

ALSO plan on cross keys. These are where many keys fit into a controlling door. (Maison keying) Your ward pins come in handy here, and you can vary the ward by using more than one ward -- ie - the main ward is say 4, then the vary in the same pin cell would be 8. A .060 jump will not cross. So here you have 5(4-8)xxx3 -- vary the 4 or 8 as needed, and keep in mind what you are designing. In the example, we used the "end master" cuts for the Maison, and if one looked, in the pinning, about 45 keys had the same constant in one position before it flipped to something else. So here the Maison was used (2-6) for one position. Other sections moved down the sheet and used other pins in that same spot, so the Maison moved as well.

Constant rotator pinning, which this is allows for almost anything you can imagine. Just follow the rules, use a magic square if you are doing this by hand, or work from a short computer master key print out.

We have several MK programs, one of which prints 20 change keys, 40 change keys, and 120 change keys. Along with the pincharts. It also makes single or double step keying, you specify which you want, and remember, what you are doing.

ALSO I have a HPC MK program which produces pages and pages of info, which is more than you would ever need for any system.

Normally one does not run into more than 300 or so change keys needed. IF your system is that large, then you need to start looking at keying things by departments alike, or in schools, "houses" - "grades" -- always think what you are doing. Use the least amount of pins in each pin cell to keep the cross keying and phantom keys down.

As I said in my original post, master keying is an art - once you learn how to do it, and have done several systems, it becomes second nature.

Again, use a good key generator to make your keys, not only the first ones, but all of them. This insures they work smoothly without clicks or binding. Never file any plug which is going to be used for a master system. This destroys the security of the thing big time. Your work should be professional and "factory" like - if you do it well, you will have repeat business.

Finally always remember duplicate keys introduce some error in the key being made. Most systems, and most locks can absorb some of this, but in time they keys will not work as subsequent generations of duplicates are made. So make your "issue" system keys all as "originals" and you will be just fine.

Hope this helps. As always, ask - I can explain more.....

Cordially,

Sinifar

PS - Final note - do I know what I talk to? Let's just say I have been in ALOA for over 40 years. Naa, don't know thing one about master work.

Sinifar

[zeke79]

Master keying is the controlled destruction of the security of a lock.

Having said that - every master pin segment put into a lock reduces the security of it and increases the number of possible phantom keys. therefore, try to have as few master pins in the cylinder as possible to do your job.

Phantom keys are keys which work your system, and are not intended to do so. They maybe keys just off your key ring, or somebody elses. A major nightmare.

For example - Schlage reserves 0 - 1 - 2 for master work only. So putting one of those in a pin set alone, as a "ward" pin, or constant will ensure that every key out there will not interchange, or be a phantom key which would work in your locks.

In fact the more pins in common, the more secure you are. For example, MK - 542123, 1 - 544763, 2- 540583 -- the common or constant 54xxx3 insures you that no key except those with those cuts in those positions will work in your system. By having cuts above and below the master, you do not expose the master by having it all the "high cuts" -- 0 - 1 - 2- 3, or all low cuts, 6 - 7 - 8 - 9. The xxx is the rotating change key pins.

Forget the "level" thing. Levels are for talking about only. Use the most direct and simplest methods to get the work done. IF you try - you can key things in groups, say, the plant department, the tool department, marketing, and / or sales. Each would be a separate change key. This way if you needed a key for say the boss of the area, it can be done with a simple hat trick. ie - M - 542123, 6AA - 544763. This would give you that department's keying, now for the boss's office - SM1 - 6 to designate the first submaster, of key 6 - 542763. This would give you the key to fit the boss's office, without exposing the master - and his key would work all the other locks, but their's would not work back. Just key his first few to the 5 - 4 - 2 then the rest. Simple and direct. This is also one of the phantom keys which I talked to earlier.

If you want levels, there are "Master mills" - keys which can go into other keyways. Schlage has Classic "C" - "CE" - "E", and these are bypassed by "H". So if you want to really jazz it up, you key one section in "C" - and one in "E", and using the same master work for both, the keyway being the difference, and then "H" becomes a grand master without any work at all. Just cut the same master for each section into "H" and you are done. You just created a grand master.

As far as how many change keys? In a six pin system you can get over 4000 usable combinations without violating any of the MACS or other rules. Again, don't wafer the thing up. One master can run this whole thing - although you may want to issue master keys for each building, or a series of buildings, in that case some work is needed.

In this example, we are going to key up a nursing home. There are four sections to it, and they want a master for each. There are about 75 rooms in each section. SO - GM - 2xxxx2, Master A - 4xxxx8, Master B - 6xxxx4 Master C-0xxxx6, and Master D- 8xxxx0. The xxxx is the rotating pins for the individual combinations. Just make sure your selection for this job does not exceed the MACS, and you are home. Each key in the system for each section would have a constant of the numbers, shown with the xxxx being the actual key for that room

Next - you don't want 1AA, 1BB, 1CC, and 1DD to "repeat" - you are going to use the same pin work for each section. So for AA, just use the pin work as printed off the sheet. For BB, reverse the sheet and work from the bottom up. For the next section, fold the system in half, and then repeat again, from the top down for CC, and the bottom up for DD. This gives a different "look" to each key, and nobody is wiser for what you did. It works. We just shipped this job out.

This also gives you room to work - expand, revise, or add unexpected sections. you have more combinations available then you used, so your "spares" become a life saver. Never pin so tight that you are in a corner and have to open something up, which may lead to a cross key. Plan your system ahead, and plan on changes. Additional master sections could be - Master E - 6xxxx0, Master F - 4xxxx6 and so on. So here you have a multi-level system which just keeps on expanding without any big sweat on your part.

IF you did this right, you used in the example, 75 keys, so on a printout of 120 keys, you are really getting a wide, non repeating system.

ALSO plan on cross keys. These are where many keys fit into a controlling door. (Maison keying) Your ward pins come in handy here, and you can vary the ward by using more than one ward -- ie - the main ward is say 4, then the vary in the same pin cell would be 8. A .060 jump will not cross. So here you have 5(4-8)xxx3 -- vary the 4 or 8 as needed, and keep in mind what you are designing. In the example, we used the "end master" cuts for the Maison, and if one looked, in the pinning, about 45 keys had the same constant in one position before it flipped to something else. So here the Maison was used (2-6) for one position. Other sections moved down the sheet and used other pins in that same spot, so the Maison moved as well.

Constant rotator pinning, which this is allows for almost anything you can imagine. Just follow the rules, use a magic square if you are doing this by hand, or work from a short computer master key print out.

We have several MK programs, one of which prints 20 change keys, 40 change keys, and 120 change keys. Along with the pincharts. It also makes single or double step keying, you specify which you want, and remember, what you are doing.

ALSO I have a HPC MK program which produces pages and pages of info, which is more than you would ever need for any system.

Normally one does not run into more than 300 or so change keys needed. IF your system is that large, then you need to start looking at keying things by departments alike, or in schools, "houses" - "grades" -- always think what you are doing. Use the least amount of pins in each pin cell to keep the cross keying and phantom keys down.

As I said in my original post, master keying is an art - once you learn how to do it, and have done several systems, it becomes second nature.

Again, use a good key generator to make your keys, not only the first ones, but all of them. This insures they work smoothly without clicks or binding. Never file any plug which is going to be used for a master system. This destroys the security of the thing big time. Your work should be professional and "factory" like - if you do it well, you will have repeat business.

Finally always remember duplicate keys introduce some error in the key being made. Most systems, and most locks can absorb some of this, but in time they keys will not work as subsequent generations of duplicates are made. So make your "issue" system keys all as "originals" and you will be just fine.

Hope this helps. As always, ask - I can explain more.....

Cordially,

Sinifar

PS - Final note - do I know what I talk to? Let's just say I have been in ALOA for over 40 years. Naa, don't know thing one about master work.

Sinifar

Awesome contribution! Having someone such as yourself with this knowledge is good. Having someone such as yourself with this knowledge who is willing to take the time to write it out and explain it is phenomenal!

I would buy this man a beer!

[btshaw]

Wow, great info - thanks. And now , a few more questions if I may...

Could you explain the use of a ward pin to enable quick change a little bit more? Also, how the ward pin would work with the Schlage 0-1-2 reserved Master pins?

Could you explain how exposing the master is prevented ?

In the nursing home example, chambers 1 and 6 were progressed to derive the MK's. Why 2 chambers - to get enough MK's (16)? Would 2xxxx6 also be one of the 16 MK's for example?

Now, on my system of 4-5 properties, each of which should have a MK and 4-5 CK's, with a single GMK, what might be wrong with the following theoretical by-hand bitting for Schlage 5 pin:

GMK 36149

MK's
36349 36549 36749 36949 (progressing only chamber 3 limits me to 4 MK's - I could progress ANY chamber to get similar results)

CK's (progressing chamber 2 only)
30349 30549 30749 30949
32349 32549 32749 32949
34349 34549 34749 34949
38349 38549 38749 38949
(a few MACS violations here I know)

My thinking is that I have reserved chamber 1 for future necessary MK's (up to 16) and chambers 4 and 5 for future CK's but I have achieved this 4 MK, 16 CK system with only 2 master pins per cylinder?

tell me what I screwed up ...

BT

[Sinifar]

Most of the systems we produce have the ward pin someplace. So if the pin is say 4, then on a quick change, only change the 4 to an 8 or 0. NOW recut all the keys with the new ward pin. It is faster to cut new keys with an ITL than it is to repin a large system, with all the new pins. Just faster, quicker and best it locks out all the old keys. Just one cut difference. At least .060 difference.

ON IC, (Best - Arrow - KSP) it is a matter of going down the hall, pulling the cores, punching one chamber clear, tossing in one new pin set in that chamber, and then stuffing the core back in. Job done.

AS far as the ends being used as the masters, that is the way our MK program works. It works with the change keys running thru the middle of the keying. SO one has to adapt to what they have. (Ilco Master Key Selector) - That is a nice little quick MK generator program. It gives me the "numbers" I need, and from there I can design the system.

As far as the 0 - 1 - 2 thing - just use them. Use them as a ward pin. When you design the system, figure that into the mix of things which you are working with.

Exposing the master is done by comparing change keys and looking for the missing cuts. Here again, the constants, or ward pins play a role. If all keys have the same constant, then trying to make a master by using the missing cuts will not work. AS most people put pins in all chambers, thus, it is possible to expose the master by just a simple comparison of the change keys.

As I have said before, Master keying is the controlled destruction of security. Every pin segment which is put into the lock makes a few phantom keys. The more pins, the more phantoms. SO keep your number of pins down to the absolute minimum which is necessary to get the desired results.

This is also a bug-a-boo for people who are trying to figure out the CONTROL key for a SFIC (Best - Arrow - KSP) core. There is no "missing cuts" which would reveal the control. IN fact many times the control will be "off time" to the normal pinning. Here one needs to get their hands on a core, and "examine" the thing - to determine the Control. No I won't tell you how, that is a really advanced situation.

ALSO I really did not want to open this one up - but, pinning "off time" -- ie - the Master is a 2, then the change cuts are 5 - 7 - 9. OR you could use 0 for the master and then 3 - 5 - 7 - 9. // ALSO the Master could be 1, then the change keys could be 4 - 6 - 8, or you could go the other way and have a deep off time master then you go the other way around. // This as well will keep from exposing the master, as most do not pin off time. Never get closer then a 3 separation in an off time set up. Yes we do that from time to time, especially in smaller systems having less than 20 change keys. It drives people absolutely nuts trying to figure out the master.

WHICH is why most pin kits, and factory listings have the master pins for the "odd" key cuts. ie - normally the master pins would be for Schlage, .030 - .060, .090, .120 // that is for 2 - 4 - 6 - 8. BUT also there is .045 for 3, .075 for 5, .105 for 7, and .135 for 9.

In a single step system one has to do with what they have, and here again the constant plays the role. OR in System 70 the 5.5 cut works for the master. In Kwikset, the 7 is the deep master, but when you fill in the pin chamber you will note, that the thing is full all the way to the top, thus ANY key except the right one with the right cut in that position will cause it not to work.

Your system will work as shown. I am not sure why you are staying with a 5 pin system, most commercial work is done in 6 pin. Working with 6 pin eliminates most keys used by the public, and gives you a wider range of numbers to work with. Unless you have a few 5 pin cylinders in the system, then add that extra pin and get on with it.

For the few 5 pin cylinders, just toss them and replace them with a C500 type universal cylinder, or if it is a fixed cylinder type, Schlage F line say, toss the thing and give the client a new lock at no charge, just to get the whole system up to 6 pin commercial standard. USE an LSDA, Marks, Dorma, or Cal Royal -- they are all good locks which will stand up to commercial abuse, and not cost you a fortune to sub into a system.

Sinifar

[zeke79]

I'll agree with LSDA. Good stuff at a fair price which does allow you to work in replacing a few locks and working them into the cost of the system.

[btshaw]

You guys are awesome - thanks. The reason I am sticking with 5 pin C keyway....i know it is too common but it is better than Qwikset....is that this is just a residential "convenience" job and I got tired of showing up at a property with the wrong keyring, so 80% rekeys and 50% of those are F series compressible bibles, so not worth the cost of upgrading to 6 pin, although the purist in me wants to. There are too many rocks and windows nearby or a good quick bootstrike and, as my grandfather told me, a lock is meant to keep an honest man honest. Initially I just wanted to master key, having had that done for my office building, but the more I learned, the less I knew, so wanted to know more.

Best,
BT

[btshaw]

Another question if you'll pardon my naivete:

In going from the GMK to the MK's, I am still confused a bit as to why one does not want to share any of the higher level bittings, i.e. the GMK and the MK's have different bittings for each of the chambers that are being progressed. The same holds true for CK's and their corresponding MK.

Why is this? In conflict to this approach, in an effort to both generate more MK's and CK's per system and use as few master pins as possible (maybe I'm wrong on this point), you would not necessarily force lower level keys to have fully separate bittings from their master.

As illustration (borrowing from a prior thread):

TMK 47230
MK 47630 (progressing chamber 3 to get MK, just using this one MK as example)
CK's are all 476xx, just showing the last two chamber progressions below for ease
52 72 92 12
54 74 94 14
56 76 96 16
58 78 98 18

but why NOT
50 70 90 10
32 52 72 92 12
34 54 74 94 14
36 56 76 96 16
38 58 78 98 18

Which would yield 24 CK's instead of 16?

is this due to key interchange/ghost keys? I started building the pin charts by hand just to follow the method and observed an inordinate amount of keys that would unintentionally operate a lock, for example:

CK 47696 would be pinned with
47230 bottom pins
xx466 Master pins

and would now be operable by:
47230 TMK
47630 MK
47290
47690
47236
47636
47296
47696 CK

so 5 ghost keys. But if you do not allow the CK's and MK to share bittings on the progressed chambers you get rid of 47290, 47690, 47236, 47636 and if you do not allow the MK and TMK to share bittings on progressed chambers, you also eliminate 47296, effectively removing all ghost keys. Mind you, I have not done this for every possible change key but I do see the pattern repeating.

Is this the reason that every example I have come across starts the progression by mandating the TMK and MK's,and similarly the MK and CK's, do not share bittings on any progressed chambers?

More interesting to me is if anyone has the formulas to show this mathematically as I do not (yet) have access to either Andrews' or Edwards' books.

Thanks for your patience and insight,
BT

[cledry]

The progressing where you do not share MK cuts with those progressed for change keys allows more versatility in a system. You do not want too big a system and you don't want to hem yourself in with too small a system. That is why talking to the customer and thinking through what they want, what they actually need, what your experience tells you they will likely want down the road is the most important part of designing the system. The customer isn't always right when it comes to a MK system. They need pushing in the right direction. Maison keying for example is something customers always seem to want, it is something we steer them away from, and in a properly designed system some middle ground is available.

[PinPopper1]

Clearly these other guys know their stuff really well and have given you some very valuable information so to avoid putting my foot in my mouth I am not going to say much on this topic but I do think it is important that somebody mention to you that master keying and grand master keying inherently weakens your security system. Be cautious when adding one or more than one master to your system in that every break in your pin stack becomes another point which can turn at the sheer line of your lock. Having master wafers in a couple pin stacks of each lock or especially multiple masters makes it exponentially easier to pick or bump.

Just food for thought.