NCCER Millwright Practice Exam

What kind of tool is referred to as a broach?

1. A tool for cutting threads

2. A tool used to cut keyways

3. A tool used for drilling

4. A tool for shaping metal

The correct answer is: A tool used to cut keyways

A broach is specifically designed for machining internal shapes and creating keyways within a workpiece. It features a series of progressively larger cutting teeth along its length, allowing it to remove material efficiently as it is pulled or pushed through a pre-drilled hole. This makes it particularly effective for forming keyways, grooves, or precision holes. The design of a broach allows for the removal of material in a way that is both precise and effective, making it a favored tool in applications where accuracy in keyway dimensions is critical. Using a broach can yield a superior finish compared to other cutting methods, contributing to its importance in machining tasks that require high precision. In contrast, a tool for cutting threads serves a different purpose, focusing on creating helical grooves for screws and bolts; a drilling tool is employed to make holes; and a shaping tool works on altering the external shapes of materials rather than creating internal features like keyways. These distinct functions highlight the specialized nature of the broach in the realm of machining.