Frame (nautical)
Encyclopedia
Keel
In boats and ships, keel can refer to either of two parts: a structural element, or a hydrodynamic element. These parts overlap. As the laying down of the keel is the initial step in construction of a ship, in British and American shipbuilding traditions the construction is dated from this event...
. Frame numbers are the numerical values given to the frames; they begin at 1 with the first bow frame, and extend to the last stern frame. The total number vary per the length of a ship.