Terminology in hole-making operations What is the correct name for the operation that enlarges an existing circular hole using a rotating single-point cutting tool on a lathe or boring machine?

Introduction / Context:
Multiple processes can produce or refine holes, but each has a specific purpose and tool type. Correct terminology is important for process planning and machine setup.

Given Data / Assumptions:

• An existing hole is present (cast, drilled, or cored).
• A single-point tool mounted in a boring bar is used.
• Goal is to enlarge and/or improve location, roundness, and finish.

Concept / Approach:
Drilling creates a hole with a multi-lip twist drill starting from solid. Reaming uses a multi-edge reamer to bring a drilled/reamed hole to final size with superior finish, removing minimal stock. Counterboring creates a flat-bottom enlargement at the hole entrance for a bolt head. Boring is the only operation among these that enlarges an existing hole using a single-point tool and can correct alignment and geometry.

Step-by-Step Solution:
Identify tool type: single-point tool in a boring bar.Identify task: enlarge and true an existing hole.Correct term: “boring.”

Verification / Alternative check:
Lathe operations lists distinguish boring from drilling and reaming by the single-point internal cutting action.

Why Other Options Are Wrong:
Drilling starts from solid; reaming is finishing at near-size stock; internal turning is a generic phrase and may not imply enlarging a pre-existing hole specifically; counterboring is a localized entrance enlargement.

Common Pitfalls:
Leaving too little stock for boring after drilling; poor tool overhang causing chatter; neglecting boring bar rigidity.

Final Answer:
Boring