Which item should be removed from the lathe chuck to avoid danger?

• A. Chuck Key
• B. Chuck Jaw
• C. Chuck Guard
• D. Spindle Sleeve

Answer: (A)

Removing the chuck key before starting is essential because it can become a dangerous projectile if left in the chuck while the spindle spins. The key is the tool used to tighten or loosen the jaws; once power is applied, a key left in place can be ejected at high speed, risking serious injury to you or bystanders and potentially damaging the workpiece or machine.

Other parts aren’t meant to be removed for safety in normal operation: the chuck jaw is an integral part of the holding mechanism, and taking it out would compromise gripping the workpiece. The chuck guard is a protective feature that should remain in place to shield you from moving parts and chips. The spindle sleeve is a fixed component of the spindle assembly and isn’t something you remove as a safety step. So, the correct practice is to remove the chuck key to prevent it from being flung during operation.