NC LOCKSMITH STUDY GUIDE QUESTIONS WITH
SOLUTIONS 2025 GRADED A+
✔✔Keying Symbol - ✔✔a designation used for a lock or cylinder combination in the
standard key coding system, e.g. AA1, XAA1, XIX, etc.
✔✔Levels of Keying - ✔✔the divisions of a master key system into hierarchies of
access, as shown in the following tables. Note: the standard key coding system has
been expanded to include key symbols for systems of more than four levels of keying.
✔✔Maison Key System - ✔✔[from the French meaning "house" key system] a keying
system, in which one or more cylinders are operated by every key (or relatively large
numbers of different keys) in the system: e.g. main entrances of apartment buildings
operated by all individual suite keys of the building
✔✔Master Key - ✔✔1. A key which operates all master keyed locks or cylinders in a
group, each lock or cylinder usually operated by its own change key. 2. To combine a
group of locks or cylinders such that each is operated by its own change key as well as
by a master key by for the entire group. 3. An automotive key which operates all or most
locks on a vehicle where there is also a valet key employed.
✔✔Master Key Changes - ✔✔the number of different usable change keys available
under a given master key.
✔✔Master Key System - ✔✔1. Any keying arrangement which has two or more levels of
keying. 2. A keying arrangement which has exactly two levels of keying.
✔✔Master Pin - ✔✔1. Usually a cylindrical shaped tumbler, flat on both ends, placed
between the top and bottom pin to create an additional shear line.
✔✔Maximum Adjacent Cut Specification (MACS) - ✔✔the maximum allowable
difference between adjacent cut depths.
✔✔Multiplex Key System - ✔✔1. A series of different key sections which may be used
to expand a master key system by repeating bittings on additional key sections. This
type of system always includes another key section which will enter more than one, or
all of the key ways. 2. A keying system which uses such key ways ans key systems.
✔✔Odometer Method - ✔✔a means of progressing key bittings using a progression
sequence of right to left.
✔✔One Column Progression - ✔✔a process where key bittings are obtained by using
the cut possibilities in one column of a key bitting array
, ✔✔Parity - ✔✔the property of being either even or odd, as the depth number of a bitting
in a combination, or the possible progressives in a given position of a two-step
progression
✔✔Pinning Chart - ✔✔a numerical diagram which indicates the sizes and order of
installation of the various pins into a cylinder. The sizes are usually regulated by the
manufacturer's reference number which equals the quantity of increments a tumbler
represents
✔✔Progression - ✔✔a logical sequence of selecting possible key bittings, usually in
numerical order from the key bitting array
✔✔Progression Column - ✔✔a listing of the key bitting possibilities available in one
bitting position as displayed in a column of the key bitting array
✔✔Progression List - ✔✔a bitting list of change keys and master keys arranged in
sequence of progression.
✔✔Random Master Keying - ✔✔an undesirable process used to master key which uses
unrelated keys to create a system
✔✔Rotating Constant - ✔✔one or more cut(s) in a key of any level which remains
constant throughout all levels and are identical to the top master key cuts in their
corresponding positions. The position where the top master key cuts are held constant
may be moved, always in logical sequence.
✔✔Rotating Constant Method - ✔✔a method used to progress key bittings in master
key system, wherein at least one cut in each key is identical to the corresponding cut in
the top master key. The identical cut(s) is moved to different locations in a logical
sequence until each possible planned position has been moved.
✔✔Row Master Key - ✔✔the one-pin master key for all combinations listed on the same
line across a page in the standard progression format.
✔✔Single Key Section - ✔✔an individual key section which can be used in a multiplex
key system.
✔✔Single Step Progression - ✔✔a progression using a one increment difference
between bittings of a given postion
✔✔Standard Key Coding System - ✔✔an industry standard and uniform method of
designating all keys and/or cylinders in a master key system. The designation
automatically indicates the exact function and keying level of each key and/or cylinder in
the system usually without further explanation.
SOLUTIONS 2025 GRADED A+
✔✔Keying Symbol - ✔✔a designation used for a lock or cylinder combination in the
standard key coding system, e.g. AA1, XAA1, XIX, etc.
✔✔Levels of Keying - ✔✔the divisions of a master key system into hierarchies of
access, as shown in the following tables. Note: the standard key coding system has
been expanded to include key symbols for systems of more than four levels of keying.
✔✔Maison Key System - ✔✔[from the French meaning "house" key system] a keying
system, in which one or more cylinders are operated by every key (or relatively large
numbers of different keys) in the system: e.g. main entrances of apartment buildings
operated by all individual suite keys of the building
✔✔Master Key - ✔✔1. A key which operates all master keyed locks or cylinders in a
group, each lock or cylinder usually operated by its own change key. 2. To combine a
group of locks or cylinders such that each is operated by its own change key as well as
by a master key by for the entire group. 3. An automotive key which operates all or most
locks on a vehicle where there is also a valet key employed.
✔✔Master Key Changes - ✔✔the number of different usable change keys available
under a given master key.
✔✔Master Key System - ✔✔1. Any keying arrangement which has two or more levels of
keying. 2. A keying arrangement which has exactly two levels of keying.
✔✔Master Pin - ✔✔1. Usually a cylindrical shaped tumbler, flat on both ends, placed
between the top and bottom pin to create an additional shear line.
✔✔Maximum Adjacent Cut Specification (MACS) - ✔✔the maximum allowable
difference between adjacent cut depths.
✔✔Multiplex Key System - ✔✔1. A series of different key sections which may be used
to expand a master key system by repeating bittings on additional key sections. This
type of system always includes another key section which will enter more than one, or
all of the key ways. 2. A keying system which uses such key ways ans key systems.
✔✔Odometer Method - ✔✔a means of progressing key bittings using a progression
sequence of right to left.
✔✔One Column Progression - ✔✔a process where key bittings are obtained by using
the cut possibilities in one column of a key bitting array
, ✔✔Parity - ✔✔the property of being either even or odd, as the depth number of a bitting
in a combination, or the possible progressives in a given position of a two-step
progression
✔✔Pinning Chart - ✔✔a numerical diagram which indicates the sizes and order of
installation of the various pins into a cylinder. The sizes are usually regulated by the
manufacturer's reference number which equals the quantity of increments a tumbler
represents
✔✔Progression - ✔✔a logical sequence of selecting possible key bittings, usually in
numerical order from the key bitting array
✔✔Progression Column - ✔✔a listing of the key bitting possibilities available in one
bitting position as displayed in a column of the key bitting array
✔✔Progression List - ✔✔a bitting list of change keys and master keys arranged in
sequence of progression.
✔✔Random Master Keying - ✔✔an undesirable process used to master key which uses
unrelated keys to create a system
✔✔Rotating Constant - ✔✔one or more cut(s) in a key of any level which remains
constant throughout all levels and are identical to the top master key cuts in their
corresponding positions. The position where the top master key cuts are held constant
may be moved, always in logical sequence.
✔✔Rotating Constant Method - ✔✔a method used to progress key bittings in master
key system, wherein at least one cut in each key is identical to the corresponding cut in
the top master key. The identical cut(s) is moved to different locations in a logical
sequence until each possible planned position has been moved.
✔✔Row Master Key - ✔✔the one-pin master key for all combinations listed on the same
line across a page in the standard progression format.
✔✔Single Key Section - ✔✔an individual key section which can be used in a multiplex
key system.
✔✔Single Step Progression - ✔✔a progression using a one increment difference
between bittings of a given postion
✔✔Standard Key Coding System - ✔✔an industry standard and uniform method of
designating all keys and/or cylinders in a master key system. The designation
automatically indicates the exact function and keying level of each key and/or cylinder in
the system usually without further explanation.
