Blob. An extremely loose place in a plate or saw blade.
Block-plane. A short plane.
Boiler-shell. The outer casing of a steam-boiler.
Bolt. 1. A holding device having a head at one end and at the other a threaded stem to receive a nut. 2. A short piece of a round log.
Bolt-cutter. A machine for cutting screw threads upon bolts or similar work.
Boring-bar. A bar that carries boring tools.
Boring-machine. A machine for boring holes in metal or wood.
Boring-mill. A form of lathe used mainly for boring.
Boring-tool. A tool for cutting out and enlarging a bore or hole.
Boss. An enveloping piece on an axle or shaft and having upon it an arm, arms, or spokes.