Master Keying Questions

[btshaw]

Hello all,

(I apologize if this is a crossposting as I originally posted this question in an old thread)

very useful forum. I am new here, not a locksmith, just a guy who ended up with too many keys... I had my office building master-keyed and would like to do so at home too. Just doing it myself as a hobby, I've rekeyed several locks, each one a learning lesson.

I've got a few properties now, I'd like each to have a MK, and I'd have the GMK. Only a few change keys per site, maybe 5 maximum, so not much expansion anticipated.

Regarding masterkeying, I've been following this thread and others and had a couple of theory questions for a 5 pin Schlage 3 Level Master scheme:

Evens or odds - is this just a convenient place to start? Is there a reason to choose one over the other?

To generate the MK's from the GMK in another thread here, you progressed the third chamber - could you just as easily progress any chamber?

I have seen conflicting information going from the GMK to the MKs - some sites say that none of the bittings should be the same as the GMK and others say to minimize the number of bitting changes so as to minimize the number of masterpins (this site) - The latter makes sense to me. KISS...

Other than using software (I like playing with the math), to choose the GMK, would I:

choose even or odd.
follow the rules:
Have at least one of the deepest possible depths of cut
Have at least one of the shallowest possible depths of cut
Not be a declining step key
Not be a straight line key
Not have the deepest cut at the bow of the key
Not have the shallowest cut at the tip of the key
Observe all other rules for the cylinders it will operate
The last one is a bit of a puzzler for a newbie...

are there any other rules to know?

best,
BT

[zeke79]

Pick odd or even and stick to it to avoid using #1 master wafers is what i have always done. This prevents thin wafers from falling into the keyway or between the plug and shell as the lock wears. I also ensure a gmk or mk contains some higher cuts than any of the change keys to prevent the modification of a change key into a mk or gmk on a restricted key system. Of course on a schlage system there is no point in worry about this as you can buy blanks anywhere.

Hopefully keysman or globallocky will chime in and help out as they have alot of experience with the commercial side of things.

[IndigoChild]

I had to create a grand master system for a very large store near here not too long ago. They were Best I-C Core cylinders. Now I know you will probably never use this because its a rather waste of money unless you have a real use for them, but When Keying up a I-C Core you need to create a core key to remove and insert the cores. The third pin stack is what controls the core keys function. If you are ever for some reason keying I-C Cores you can absolutely progress a different cut. Just make sure the core key is a different depth than all the others.

As far as evens or odds. I like to chose which there are more of for that keyway. For example weiser has 9 depths. There are more evens. leaving me with more possibilities.

[lockstar5000]

What is the reasoning for choosing evens or odds? In my locksmith class, our instructor didn't go into this. When we masterkeyed our locks for our demo, we did not choose evens or odds, we utilized all pin depths. So whats the logic behind this?

[GWiens2001]

The reason is primarily to avoid using a 1 step wafer, which may flip and get stuck, or fall out of the pin channel and jam the plug or pin stack. If you use at least a depth of 2 cuts for a master wafer, it will most likely not have any problems due to a wafer slipping out of place.

Gordon

[lockstar5000]

a little research says that this is to avoid being forced because they are too close together. i.e. you would not use a key with bitting 54327, because of the 5432, correct?

Does this physically mean that the 5cut could force the 4pin to rotate at the shear line in the next chamber due to sloppy tolerance? Im having trouble visualizing this.

[lockstar5000]

OK so then choosing evens or odds is solely to eliminate a #1 chip, makes sense. Thank you.

[lockstar5000]

Just so I am perfectly clear on this--The 2 step preference is referring to the difference betwwen pins in a single chamber, doesn't have anything to do with adjacent CHAMBERS, only adjacent PINS

[Altashot]

Another reason to use even-odd-even-odd-even (01010) for example, is to prevent cross-over/interchange in the event that a master key system has to be re-done. On a re-do master key system the opposite would be used odd-even-odd-even-odd (10101).

Makes sense?

M.

[lockstar5000]

now I am confused completely.

are you saying 1st cut even, 2nd odd, 3rd even, 4th odd, 5th even on a 5 chamber cylinder? like a cut of 54327(even-odd-even...) as opposed to 51357(all odd)??

This is getting me confused

[Altashot]

a little research says that this is to avoid being forced because they are too close together. i.e. you would not use a key with bitting 54327, because of the 5432, correct?

Does this physically mean that the 5cut could force the 4pin to rotate at the shear line in the next chamber due to sloppy tolerance? Im having trouble visualizing this.

By "too close together" I thing they mean that a masterkey with a bitting of, say, 54327 should not have a change key that has a bitting of 65438. It is only one increment deeper and pulling that change out a little bit would make the pins ride up the ramp and would work as a masterkey if used in that fashion.

It can get very confusing. And yes this is what I mean.

[lockstar5000]

Found this which helps me:

One common method:

Designate each pin chamber either "odd" or "even". It's common
to alternate odd-even-odd-even-odd or the other way around.
This makes sure that there are no cases where any two keys
in the system vary by only one cut (.015) but are at least .030
different in at least one place.

[lockstar5000]

This:

"By "too close together" I thing they mean that a masterkey with a bitting of, say, 54327 should not have a change key that has a bitting of 65438. It is only one increment deeper and pulling that change out a little bit would make the pins ride up the ramp and would work as a masterkey if used in that fashion."

makes perfect sense. Think I got it now thanks alot.

[Altashot]

This is very true. It's just difficult to put in words. It all make sense to me but I have years of experience and can easily visualize it. Maybe I'm not explaining it properly either, English is not my native tongue.

M.

[Sinifar]

Look, Master keying is an art.

Don't get hung up on the "O-E" order. We use almost anything.

As far as "steps" - you need to follow the MACS, and don't exceed the numbers, as the pin land, the thing the pin sits on will be too small for the pin to sit on.

Don't use a # 1 difference, ie - .015, or less. Always use a "two step" progress - 0 - 2 - 4 - 6 - 8 , or 1 - 3 - 5 - 7 - 9.

Use a computer generated system. It gives you more of a "shotgun" progress rather than just following the normal progress. ie - 370, the next one would be 372, the next one 374, and so on. In the right way, the keys come out 372, 594, 152, 370 - and so on. this prevents some goof from figuring out what the next office, or door could be.

If you are going to work a system out by hand, start with a "magic Square" - that is draw a box with enough lines to cover all the numbers you are using. Progress across and down the box like this - across - the highest numbers for each pin cell. Down the actual numbers in each possible location. "X" off the master key cuts, then use the rest in your key lists. You end up with a grid of 5 or 6 across, and 5 down. This is how we start teaching the art of this job.

Put a "ward" pin in the system. THAT is every key in it has the same cut. It doesn't matter where, first, middle or last. Just have the same cut on all keys. This gives you a "quick change" for that late night call to rekey FAST due to some emergency without having to redesign the whole thing. Trust me it works well. For your ward cut use something like a middle cut, a 3, 4, or 5 for the first go around. Then you can flip the system by using 0, 1 or 2 for the next one, and finally 6,7, or 8 for the last rekey.

Be aware there are "two step" systems out there like Kwikset, and Emhart - Corbin - Russwin System 70.

Here you can use 1, 2, 3, 4, 5, 6 in each pin cell with no problems as it is a -- Kwikset .023 between cuts, System 70 - .028 between cuts. System 70 also has a 5.5 cut which is used for some factory Master systems, and Emart LFIC systems.

Medeco is also a two step system, but there is an older "single step" Medeco, both regular and Biaxial out there.

Getting into either Medeco or Emhart high security with the 30 degree angle pins is beyond this forum, and should only be worked on by security professionals. Trust me, I have seen some really bad hack jobs.

After nearly a half century in the business I am still amazed at the mis-information out there on the art of master keying.

Always remember - ANY key can be a "master"

Always use LAB pins, .003 if possible to keep the pining "tight" -

NEVER file any lock plug to get your keys to work. If your keys do not work, you need a better method of generating the originals.

ALWAYS use a good key generator. We have a Framon # 2 which works well, and make ALL our key systems keys on it as originals, never any duplicates due to the cutting errors which creep in on duplicates. A HPC 1200 series - any of them will also work well. There are others, HOW much do you want to invest in this business, and what will your rate of return be?

Finally, don't be "cute" and try to introduce your own kinks into any keying. Master or just rekeys. Nothing irks people off more than finding off time keys,which are not made to the right cutting specs, odd spaced keys which work on the opening / closing ramps - worse "tip operators" - pins which ride on the opening angle of the key blank, and do not actually sit on a pin land. These can cause real lockouts.

More if you ask.

YES I can make a lock "bump proof" - we have and it works.

Sinifar