On a vessel's hull, a strake is a longitudinal course of planking or

plating Plating is a finishing process in which a metal is deposited on a surface. Plating has been done for hundreds of years; it is also critical for modern technology. Plating is used to decorate objects, for corrosion inhibition, to improve solderab ...

which runs from the boat's stempost (at the bows) to the sternpost or transom (at the rear). The garboard strakes are the two immediately adjacent to the

keel The keel is the bottom-most longitudinal structural element of a watercraft, important for stability. On some sailboats, it may have a fluid dynamics, hydrodynamic and counterbalancing purpose as well. The keel laying, laying of the keel is often ...

on each side. The word derives from traditional wooden

boat building Boat building is the design and construction of boats (instead of the larger ships) — and their on-board systems. This includes at minimum the construction of a hull, with any necessary propulsion, mechanical, navigation, safety and other ser ...

methods, used in both carvel and clinker construction. In a metal ship, a strake is a course of plating.

Construction

In small boats strakes may be single continuous pieces of wood. In larger wooden vessels strakes typically comprise several planks which are either scarfed, or butt-jointed and reinforced with a butt block. Where the transverse sections of the vessel's shape are fuller, the strakes are wider; they taper toward the ends. In a riveted steel ship, the strakes were usually lapped and joggled (one strake given projections to match indentions in the one adjoining), but where a smoother finish was sought they might be riveted on a butt strap, though this was weaker. In modern welded construction, the plates are normally butt-welded with full penetration welds all round to adjoining plates within the strake and to adjoining strakes.

Terminology

In boat and ship construction, strakes immediately adjacent to either side of the

are known as the ''garboard strakes'' or ''A strakes''. The next two are the first broad or ''B'' strake and second broad or ''C'' strake. Working upward come the bottom strakes, lowers, bilge strakes, topside strakes, and uppers also named sequentially as the ''D'' strake, ''E'' strake, etc. The uppermost along the topsides is called the sheer strake. Strakes are joined to the

stem Stem or STEM most commonly refers to: * Plant stem, a structural axis of a vascular plant * Stem group * Science, technology, engineering, and mathematics Stem or STEM can also refer to: Language and writing * Word stem, part of a word respon ...

by their hood ends. A rubbing strake was traditionally built in just below a carvel sheer strake. It was much less broad but thicker than other strakes so that it projected and took any rubbing against piers or other boats when the boat was in use. In clinker boats, the rubbing strake was applied to the outside of the sheer strake. Many current pleasure craft reflect this history in that they have a mechanically attached (and therefore replaceable) rub rail at the location formerly occupied by a rubbing strake, often doubling to cover the joint between a GRP hull and its innerliner. Inflatable

dinghies A dinghy is a type of small boat, often carried or Towing, towed by a Watercraft, larger vessel for use as a Ship's tender, tender. Utility dinghies are usually rowboats or have an outboard motor. Some are rigged for sailing but they diffe ...

and

RIB In vertebrate anatomy, ribs () are the long curved bones which form the rib cage, part of the axial skeleton. In most tetrapods, ribs surround the thoracic cavity, enabling the lungs to expand and thus facilitate breathing by expanding the ...

s usually have a rubbing strake (typically a glued-on rubber

extrusion Extrusion is a process used to create objects of a fixed cross section (geometry), cross-sectional profile by pushing material through a Die (manufacturing), die of the desired cross-section. Its two main advantages over other manufacturing pro ...

) at the edge. A "stealer" is a short strake employed to reduce the width of plank required where the girth of the hull increases or to accommodate a tuck in the shape. It is commonly employed in carvel and iron/steel shipbuilding, but very few clinker craft use them.

Sources

{{sailing ship elements Shipbuilding fi:Laidoitus