Which statement about the center drill on a lathe is true?

• A. It is used to remove burrs from workpieces
• B. It is used to chamfer edges
• C. It is used to gauge diameter
• D. It centers the drill and guides drilling to produce a precise center or start for workpiece alignment

Answer: (D)

Center drills are designed to locate and start a hole precisely while aligning the workpiece for turning. The tip creates a true center that mates with a lathe center, and the built-in pilot guides the drill bit so subsequent drilling starts exactly where intended. This setup reduces drift and runout, giving a stable, accurate starting point for drilling and for alignment of the workpiece between centers. It’s not primarily used for removing burrs, chamfering edges, or gauging diameter, which is why that statement about centering and guiding drilling to produce a precise center or start is the best description.