Garboard strake illustration for the article

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

plating Plating is a surface covering in which a metal is deposited on a conductive 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 impro ...

which runs from the boat's stempost (at the bows) to the

sternpost A sternpost is the upright structural member or post at the stern of a (generally wooden) ship or a boat, to which are attached the transoms and the rearmost left corner part of the stern. The sternpost may either be completely vertical or may ...

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 on a vessel. On some sailboats, it may have a hydrodynamic and counterbalancing purpose, as well. As the laying down of the keel is the initial step in the construction of a ship, in Br ...

on each side. The word derives from traditional wooden

boat building Boat building is the design and construction of boats and their systems. This includes at a minimum a hull, with propulsion, mechanical, navigation, safety and other systems as a craft requires. Construction materials and methods Wood Wo ...

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 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 An inflatable is an object that can be inflated with a gas, usually with air, but hydrogen, helium and nitrogen are also used. One of several advantages of an inflatable is that it can be stored in a small space when not inflated, since inflata ...

dinghies A dinghy is a type of small boat, often carried or towed by a larger vessel for use as a tender. Utility dinghies are usually rowboats or have an outboard motor. Some are rigged for sailing but they differ from sailing dinghies, which ...

and RIBs usually have a rubbing strake (typically a glued-on rubber

extrusion Extrusion is a process used to create objects of a fixed cross-sectional profile by pushing material through a die of the desired cross-section. Its two main advantages over other manufacturing processes are its ability to create very complex ...

) 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