Construction and rigging Traditional models are constructed of some light, seasoned
wood, such as
pine, preferably
white pine,
white cedar or
mahogany free from knots. The
hull may either be hollowed out of a solid block of wood, or cut from layers of
planks in the so-called bread-and-butter style, or planked over a frame of keel and cross-sections. The first two methods are used in constructing
dugout models. Hollowing out from the solid block entails a great deal of labor and has therefore fallen into disfavor. In the bread-and-butter style a number of planks, which have been shaped to the horizontal sections of the model and from which the middle has been
sawn out, are
glued together and then cut down to the exact lines of the design, templates being used to test the precision of the curves. In the planked, or built-up model, which is generally chosen by more expert builders, the planks are tacked to the frame, as in the construction of large vessels. Hulls may also be formed from modern plastics, which may be purchased from a manufacturer as thermomoldings or fiberglass layups or fabricated by the modeler, by first making a positive model from clay or plaster (or using an existing model's hull) and then creating a negative mold from fiberglass or plaster. Models may be exaggerated cutters, so far as their underbodies are concerned, or, more often, are fitted with fin-keels weighted, after the manner of full-sized yachts. They may have any rig, but
schooner and
sloop rigs are most common, the latter being the favorite for racing on account of its simplicity.
Mechanical sailing controls For uncontrolled sailing craft some form of steering control is required, since with a fixed rudder position the model will turn into the wind. Three kinds of steering-gear are used, the weighted swinging
rudder, the main-sheet balance gear, and the steering vane, the object of each being to keep the model on a true course, either before or against the
wind. Models are often sailed without dynamic control of the rudder, but although a perfectly built boat will sail readily against the wind without steering gear, it is almost impossible to keep it on its course before the wind without some contrivance to check for divergence. The setting of the steering gear and sheet positions must be adapted to the wind conditions and this is a subtle art to master. These controls are the traditional methods, for more than 100 years before the advent of radio control and they continue to be used worldwide.
Weighted rudder method This is accomplished by the weighted rudder, which falls over when the vessel heels and tends to counteract the force of the breeze. There are two varieties of the weighted rudder, in the first of which the weight, usually lead, is fixed to the edge of the rudder, while in the second the weight, usually a ball of lead, is made to run on the tiller above the
deck, so that it can be placed further forward or aft, according to the force needed to overcome the influence of the wind. The weighted rudder is almost universal in the
British Isles. Weights are also incorporated into the other, following methods.
Main sheet balance method The preferred method in the
United States uses the main-sheet balance gear, in which the boom is connected with the tiller in such a manner that, when it swings out with a pressure of wind, the rudder is automatically pulled round sufficiently to keep the yacht in its course. This will usually involve some sort of return spring so that the mechanism is responsive to the wind. This apparatus is particularly efficient in sailing before the wind. More modern, computer-based RC transmitters often have mixing circuitry integral to their design, that can "mix" the sheet-balancing, operated with a sail control servo, internally in the transmitter's computerized encoder unit, with the rudder control.
Wind vane method A more accurate method is to use a separate rudder vane; this is made from a plank of light wood such as balsa. The vane is operated in two principal positions, one for upwind sailing, the other for downwind. While some modelers object that the model craft will not be a plausible representation of its full-sized prototype, real long-distance cruising boats are frequently steered with dedicated windvanes of varying complexity (mechanical or electronic), occasionally with a line attached to a sheet, and never using weighted rudders.
Radio control in
Central Park in New York City Radio control may be used in many locations. Typically two controls are provided for sailing yacht models, a general–purpose small servo for rudder control and a specialized
sail winch to draw in the mainsheet and jib. Motorized craft control rudder and throttle, and perhaps other functions such as reversing, lighting, and mechanical novelties. Other radio controlled watercraft hobbies include the operation and battle engagement of scale model warships (with gas-operated guns intended to sink opponents), and various high speed racing craft driven by powerful engines. ==Regattas==