What is one of the primary uses of a reamer in metalworking?

A reamer is specifically designed to enlarge existing holes to precise diameters, ensuring a smooth and accurate finish. It is particularly useful in achieving a higher level of dimensional accuracy and surface finish than can be attained with a standard drill bit. Reamers are commonly used in metalworking applications, especially when creating assembly holes that require a tight fit for pins, bolts, or dowels.

The characteristic flutes of a reamer allow it to remove material from the sides of a pre-drilled hole rather than the center, contributing to its ability to create a polished surface and exact diameter. This precision is essential in assembly processes, where the fit of components must meet strict tolerances to ensure functionality and safety.

Other options provided do not align with the primary function of a reamer. Cutting new grooves is a different process involving tools specifically designed for that purpose. Sharpening edges of tools typically requires grinders or honing tools, rather than reamers. Drilling pilot holes is the role of drill bits, which create the initial openings before any reaming takes place. Each of these tasks requires different tools designed to achieve distinct objectives in metalworking.