Straight Shank Counterbores
- Counterboring is the enlargement of a portion of a hole that has previously been formed.
- If the counterbored portion is shallow (1/8" or less), the operations is usually known as spot-facing; for example, a flat seat for a bolt head or nut.
- If, on the other hand, the hole is enlarged to a considerable depth, it is designated as counterboring.
- These counterbores are made of two-piece construction, having an integral shank and counterbore-cutter, and a pilot that is interchangable, which provides flexibility in the use of the tool.