We live in an 8-plex. Each unit only has one key. These keys open the front gate, the common laundry room and the door to each unit.
How is it that everyone’s key does not open all the units?
We live in an 8-plex. Each unit only has one key. These keys open the front gate, the common laundry room and the door to each unit.
How is it that everyone’s key does not open all the units?
Sounds like a kind of Master Key system.
Have you tried your key in one of the other apartments?
The front door and the laundry room locks are missing a few tumblers (usually the ones on the keyring end). Basically, the common locks only look at the first several “digits”, and don’t look at the last ones.
Master keys like this are common.
In the long-gone days of my youth, my father owned a small janitor business, with contracts at several medium-size office buildings in the area. Every office had its own key (I would hope), and I suppose those individual keys would also all open the main doors into the lobby. But my father had a key that would open ALL the doors – it got him into the lobby and into all of the offices.
Note that this seems to imply a scheme with the tumblers a bit more complicated than Chronos describes. One the one hand, you have many keys (the individual office keys) that all open one common door (the lobby) – that is the scenario that Chronos explains – but on the other hand, you also have one key that opens many doors. So you have a system with various overlapping subsets of keys opening various overlapping subsets of doors.
On a 5 pin key lock system there are up to possible 1024 change keys that can be cut, less improper combinations.
On a 6 Pin key lock system there are up to possible 4096 change keys that can be cut,less improper combinations .
On a 6 pin system there will be,
1 Great-Great Grand works in all locks.
4 Great Grand Masters works in 1/4 of the locks.
16 Grand Masters works in 1/16 of the locks.
64 Grand Masters (or page masters) works in 1/64 of the locks.
The key system is broken into 64 pages and on each page is
4 column masters
16 block masters
16 Row masters.