The ___hole is drilled to receive the threaded part of a wood screw.
A shank
B counterbore
C countersink
D pilot
The correct answer and explanation is:
The correct answer is D. pilot.
A pilot hole is a small, pre-drilled hole that is made in wood or other materials to guide a screw. The purpose of the pilot hole is to create a space where the screw can easily enter without damaging the surrounding material. When a wood screw is being driven into wood, the pilot hole is necessary to reduce the friction between the screw and the wood, helping the screw to go in smoothly and without splitting the wood.
A shank is the smooth portion of a screw, not the hole. It is the part of the screw that extends between the head and the threaded portion. The counterbore is a hole that allows a screw head to sit flush with or below the surface of the material. A countersink is a conical-shaped hole made to allow the screw’s head to sit flush with the surface, typically used for screws with flat heads.
The pilot hole is drilled first, and its size is usually smaller than the screw’s outer diameter but larger than its core diameter, allowing the screw to thread into the material securely. Without a pilot hole, driving a screw into dense or hard material could cause damage like cracking or splitting. Furthermore, in softwoods, a pilot hole helps prevent the wood from deforming, while in hardwoods, it prevents excessive resistance during screw installation.
The size of the pilot hole is important and typically depends on the size of the screw and the material being drilled into. Too small a hole could make driving the screw difficult, while too large a hole may not allow the screw to hold securely.