CML Lock Mechanisms & Hardware 4

Question 1

What is a 'master wafer' (or master disc) in a master-keyed pin tumbler lock?

Accepted Answer

An extra pin segment added to a pin stack to create an additional shear line for a master key

Answer

A master wafer (also called master pin) is a thin pin segment inserted into a pin stack to create a second shear line, allowing both the change key and the master key to operate the cylinder.

Question 2

What is the purpose of a 'key control' system in a commercial facility?

Accepted Answer

To restrict unauthorized duplication of keys through patented keyways and registered key blanks

Answer

Key control systems use proprietary, patented keyways and registered key blanks that cannot be legally duplicated without authorization, controlling who can obtain additional copies.

Question 3

A locksmith is working with a Schlage B-series deadbolt. What is the standard throw length of this bolt?

Accepted Answer

1 inch

Answer

Standard residential and light commercial deadbolts, including the Schlage B-series, have a 1-inch bolt throw, which is the minimum recommended by most security standards.

Question 4

Which mechanism in a high-security padlock is designed to protect against bolt-cutter attacks?

Accepted Answer

A hardened steel shackle with boron or chromium alloy

Answer

High-security padlocks use shackles made from hardened boron alloy or chrome-moly steel, which is significantly harder than standard steel and resists cutting with bolt cutters.

Question 5

What is 'mushroom pinning' and why is it used?

Accepted Answer

A technique using mushroom-shaped driver pins to increase resistance to picking by creating false sets

Answer

Mushroom (or spool) pins have a shaped profile that creates a 'false set' during picking attempts, causing the plug to partially rotate and then bind again, frustrating standard single-pin picking.

(CML) Certified Master Locksmith Practice Test

(CML) Certified Master Locksmith Practice Test

CML Lock Mechanisms & Hardware 4