Boring operation

Boring – A boring tool enters the workpiece axially and cuts along an internal surface to form different features. The boring tool is a single-point cutting tool, which can be set to cut the desired diameter by using an adjustable boring head. Boring is commonly performed after drilling a hole in order to enlarge the diameter or obtain more precise dimensions.

Counter boring operation

Counter boring – A counter bore tool enters the workpiece axially and enlarges the top portion of an existing hole to the diameter of the tool. Counter boring is often performed after drilling to provide space for the head of a fastener, such as a bolt, to sit below the surface of a part. The counter boring tool has a pilot on the end to guide it straight into the existing hole.

Countersinking

A countersink tool enters the workpiece axially and enlarges the top portion of an existing hole to a cone-shaped opening. Countersinking is often performed after drilling to provide space for the head of a fastener, such as a screw, to sit flush with the workpiece surface. Common included angles for a countersink include 60, 82, 90, 100, 118, and 120 degrees.

Reaming operation

Reaming – A reamer enters the workpiece axially and enlarges an existing hole to the diameter of the tool. Reaming removes a minimal amount of material and is often performed after drilling to obtain both a more accurate diameter and a smoother internal finish.