Wooden Boat Terminology

Keel – the underside fore-aft backbone of the boat running at the very bottom of the structure and usually the heaviest timber

Horn Timber – the aft part of the Keel connecting between the Ballast and the Transom

Deadwood – A filler piece between the Keel and the lead Ballast at the bottom of keel appendage

Frames (also incorrectly called Ribs) – the vertical timbers than run in opposing pairs at regular intervals along the Keel making up the sides of the boat and providing the hull shape

Floors – timbers running over the Keel to connect each set of Frames to each other and to the Keel.

Sheer Clamp  (or just the Clamp) – a fore-aft timber on each side connecting the top of each set of Frames to the Deck Beams and defining the sheer line of the vessel

Transom – board forming the stern of the vessel

Ballast – the lead or iron weight bolted to the bottom of the keel and shaped to be part of the bottom line of the boat (sometimes incorrectly called the keel)

Knees – reinforcing pieces of wood, metal or other material to provide additional support and strength between the Deck beams and Clamp

Deck Beams – timbers running athwartships connecting the top of each set of frames to prevent the hull from spreading apart and to support the deck

Carlins – fore and aft support deck beams which which support the outside of openings in the deck for cockpits, cabins, hatches

Jack Beams – short Deck Beams which connect the Carlins to the Frames

Breasthook – triangular piece of reinforcing wood connecting the front end of each of the port and starboard Clamps to the Stem (front end of the Keel)

Quarter Knees – reinforcing wood that connects the trailing edge of each Clamp to the Transom and Deadwood