Millwright Level 1 Practice Exam

A depth micrometer is primarily used for what purpose?

1. Measuring length

2. Measuring depth

3. Measuring diameter

4. Setting a reference point

The correct answer is: Measuring depth

A depth micrometer is specifically designed for measuring the depth of holes, slots, or recesses. Its construction typically includes a rod or an extension that allows the user to gauge the distance from the surface to the bottom of an opening accurately. This instrument is essential in precision machining and manufacturing, where depth measurements are critical for ensuring that parts fit together correctly and function as intended. While the other options mention measuring length, diameter, or setting a reference point, those are not the primary function of a depth micrometer. Length measurements are typically done with standard micrometers or calipers, diameter measurements require different tools like calipers or bore gauges, and setting a reference point is more associated with instruments like levels or plumb bobs, not specifically depth micrometers. Thus, the focus on measuring depth is what sets the depth micrometer apart for its intended purpose in the machinist's toolkit.