Locksmith Advanced Topics 3 — Questions and Answers
Question 1: Which safe lock type uses a relocker that activates if the safe dial or lock is attacked?
- Key-operated cam lock
- Group 2 combination lock
- Day-gate lock
- Mechanical relocker (Correct answer)
Correct answer: Mechanical relocker
A mechanical relocker is a secondary locking device that engages when glass or metal relocker plates are broken during an attack, making the bolt work immovable.
Question 2: In an electrified door hardware installation, what is the function of a 'request to exit' (REX) device?
- It locks the door when an intruder is detected
- It signals the access control system to unlock the door for egress (Correct answer)
- It powers the electric strike
- It records entry and exit timestamps
Correct answer: It signals the access control system to unlock the door for egress
A REX device, such as a motion sensor or push bar, sends a signal to the access control panel to release the door lock so occupants can exit freely.
Question 3: A locksmith decodes a padlock using the 'shackle shimming' technique. What does this exploit?
- A weakness in the shackle spring tension
- The gap between the shackle and the locking lug to bypass the latch (Correct answer)
- The softness of the padlock body metal
- The tolerances in the keyway warding
Correct answer: The gap between the shackle and the locking lug to bypass the latch
Shimming inserts a thin metal shim into the shackle gap to depress the spring-loaded latch, allowing the shackle to release without a key.
Question 4: What is the purpose of 'key control' in a master key system?
- Limiting the number of keys cut per day
- Preventing unauthorized duplication of keys in the system (Correct answer)
- Controlling the order in which keys are issued
- Reducing the total number of key levels
Correct answer: Preventing unauthorized duplication of keys in the system
Key control involves using patented keyways, restricted blanks, and authorization records to ensure only authorized personnel can have duplicate keys made.
Question 5: When installing a door closer, what adjustment controls the speed of the door during the final few degrees of closing?
- Sweep speed valve
- Backcheck valve
- Latch speed valve (Correct answer)
- Spring power adjustment
Correct answer: Latch speed valve
The latch speed (or latching) valve controls how quickly the door moves in the final inches of closure, allowing it to latch without slamming.
Question 6: Which pin tumbler lock feature is designed to defeat 'impressioning' attacks?
- Longer key bow
- Serrated or spool driver pins (Correct answer)
- Wider keyway
- Deeper bottom pins
Correct answer: Serrated or spool driver pins
Serrated or spool-shaped driver pins create false sets that resist the consistent upward pressure used in impressioning, making it difficult to mark cut locations.
Question 7: What is a 'floating' or 'variable' shear line in a high-security sidebar lock?
- A shear line that shifts based on key rotation angle
- An additional sidebar that must align for the cylinder to rotate (Correct answer)
- A shear line that only engages under high torque
- A shear line with no fixed driver pin height
Correct answer: An additional sidebar that must align for the cylinder to rotate
High-security locks like Medeco use a sidebar that must be retracted by rotating the bottom pins to specific angles in addition to lifting them to the correct height.
Locksmith Advanced Topics 3
Which safe lock type uses a relocker that activates if the safe dial or lock is attacked?