Bottoming-tap. A tap having a full thread up to its very end so that it will cut a full thread to the bottom of a hole.

Box-chuck. A rectangular two-jawed chuck used by brass finishers.

Box-tool. A tool used in screw machines and turret heads, and which guides the work while it is being operated upon. A box tool in many cases carries more than one cutting tool.

Box-wrench. A wrench which fits over the head of the bolt and passes endways upon it.

Brace. 1. A rod, bar, or beam that braces or supports. 2. A device for revolving cutting tools.

Bracket. A projecting frame that is bolted to its supporting pieces or frame.

Brad-awl. An awl for piercing small holes in wood and having a wedge-shaped end.

Branch-pipe. A pipe leading out of another.

Brass-and-brass. A term used to denote that the two brasses or boxes of a bearing are locked together by the key, cap, or set-screw.

Brasses. Pieces fitted into a frame and intended to afford a bearing for a journal.