Machine Safety Flashcards
7 cards from real CNC practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Machine Safety flashcards as text
What is the safest method for removing a broken end mill from a CNC spindle taper?
Answer: Use the machine's drawbar release function with the spindle fully stopped
The machine's drawbar release is the correct mechanical method for releasing a tool holder safely, always performed with the spindle confirmed stopped.
Which of the following describes a 'two-hand control' safety device used on some CNC punch or press operations?
Answer: A device requiring simultaneous activation of two controls to initiate a hazardous motion
Two-hand controls require both hands to be on controls simultaneously, ensuring the operator's hands are clear of the hazard zone before the machine cycles.
What is the greatest danger of leaving a CNC machine unattended while it is running an automated cycle?
Answer: A fault, crash, or fire may go undetected and escalate
An unattended machine cannot be stopped quickly when a fault, tool breakage, or fire occurs, allowing a minor event to escalate into major damage or injury.
How should long bar stock that extends beyond the headstock of a CNC lathe be handled safely?
Answer: Enclose or guard the protruding stock and use a bar feeder or steady rest
Bar stock extending past the headstock can whip at dangerous speeds; a bar feeder, steady rest, or full enclosure prevents this from injuring bystanders.
What role does a CNC machine's spindle orientation (M19) command play in safe tool changes?
Answer: It locks the spindle at a fixed angular position so the tool key aligns correctly
M19 orients and locks the spindle at a precise angle to ensure the tool-holder key aligns with the spindle drive slots during automatic or manual tool changes.
A new operator is about to run their first production part after training. Which of the following is the safest initial action?
Answer: Set the feed rate override to 0%, confirm all offsets, then slowly increase override while monitoring the first pass
Starting at 0% feed override and gradually increasing it during the first pass allows the new operator to observe tool behavior and intervene before a crash occurs.
Which body part is most commonly injured by CNC machine operations according to occupational safety data?
Answer: Hands and fingers from contact with tools, chips, or pinch points
Hands and fingers are the most frequently injured body parts in CNC operations due to contact with sharp tools, flying chips, and pinch points during setup and loading.