On a vessel'shull, astrake is a longitudinal course ofplanking orplating which runs from the boat'sstempost (at thebows) to thesternpost ortransom (at the rear). Thegarboard strakes are the two immediately adjacent to thekeel on each side.
The word derives[1][2] from traditional woodenboat building methods, used in bothcarvel andclinker construction. In a metal ship, a strake is a course of plating.
In small boats strakes may be single continuous pieces of wood. In larger wooden vessels strakes typically comprise several planks which are eitherscarfed, orbutt-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 ariveted steel ship, the strakes were usually lapped and joggled (one strake given projections to match indentions in the one adjoining),[3] 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.
In boat and ship construction, strakes immediately adjacent to either side of thekeel are known as thegarboard strakes orA strakes. The next two are the first broad orB strake and second broad orC strake. Working upward come the bottom strakes, lowers, bilge strakes, topside strakes, and uppers also named sequentially as theD strake,E strake, etc. The uppermost along the topsides is called the sheer strake.[4] Strakes are joined to thestem by their hood ends.[5]
A rubbing strake was traditionally built in just below acarvel 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. Inclinker 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 aGRP hull and its innerliner.Inflatabledinghies andRIBs usually have a rubbing strake (typically a glued-on rubberextrusion) at the edge.[6]
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.[7] It is commonly employed in carvel and iron/steel shipbuilding, but very few clinker craft use them.