Millwright Level 1 Practice Exam

How does the speed and feed of a reamer compare to that of a drill?

1. RPM is faster and feed is slower

2. RPM is slower and feed is faster

3. Both speed and feed are the same

4. RPM is slower and feed is slower

The correct answer is: RPM is slower and feed is faster

The correct answer, that the RPM is slower and the feed is faster for a reamer compared to a drill, reflects the distinct functions and design of these tools. Reamers are used primarily for finishing holes that have already been drilled to a specific size. Their purpose is to improve the diameter accuracy and surface finish of the hole. Due to this, reamers operate at a slower spindle speed (RPM) than drills. The slower speed allows for more precise control and a finer finish, reducing the potential for overheating and tool wear, which is crucial when working with hardened materials. On the other hand, reamers typically use a faster feed rate. This is because their cutting edges are designed to remove smaller amounts of material in a single pass compared to a drill, effectively allowing them to cut more efficiently through the already established hole. A faster feed helps the reamer engage with the material effectively, leading to a smoother operation and improved finished quality. In summary, the characteristics of reamers with respect to their slower RPM and faster feed rate are critical to their function in machining, distinguishing them from drills that are intended for initial hole creation rather than precision finishing.