Rigging Small Sailboats
Chapter 3
.....spar components
Page 5The GOOSENECK is the fitting used to connect the boom to the mast and allow it to move freely, like a universal joint. On the small lateen rig boats the gooseneck is two connected loops which rotate independently (see Fig. 3-14). On conventional rigs, a basic gooseneck is the fixed base type which fastens to the mast. For better sail adjustment, the type of gooseneck which slides on a track or in the mast groove is superior (see Fig. 3-15). Whichever of these types is used, they can be bought as non-swiveling or as a ROLLER REEFING type. The non-swiveling type as shown in Fig. 3-15, does not permit the boom to rotate. The roller reefing type shown in Fig. 3-16, is used so the boom can rotate and allow the sail to be rolled onto the boom in order to reduce sail area when sailing in heavy winds. Goosenecks come in many styles both for wood and aluminum booms with or without the roller reefing feature.
The CLEW OUTHAUL at the other end of the boom is similar in function to the masthead fitting. It is used to attach the clew of the sail to the boom. Where the mainsail is small, the clew outhaul is sometimes nothing more than a line tied to a cleat. Another method is to use a sheave in the end of the boom in order to gain some leverage so the sail can be pulled taut (see Fig. 3-17). With larger mainsails, the clew outhaul is best a slide fitting located on a length of track, or a type which fits into the boom groove if there is one (see Fig. 3-18). On aluminum booms, and especially when roller reefing is used, a boom outhaul fitting is used which performs the clew outhaul function as well as providing a tang for attaching the hardware used to control the sail .
Other incidental fittings may often be attached to the spars as well. CLEATS (a fitting used to belay or secure a line, Fig. 3-19) or BOOM BAILS ("U"-shaped straps used to attach blocks to the boom, Fig. 6-2) are commonly used. A BOOM CRUTCH is another item sometimes used, which is not really a part of the boom. The boom crutch holds up the boom when the sails are furled and when hoisting the sail, in order to keep the boom in its proper position.
FIG. 3-14 This is a gooseneck used on boats with lateen rigs such as shown in Fig. 2-5. The small loop is secured to the boom while the mast fits loosely into the big loop so that the gooseneck can move freely along the mast. |
FIG. 3-15-A typical gooseneck showing the tack shackle, downhaul eye, and tangs which lap each side of the boom. Note the relieved area for feeding the sail bolt rope and installing the gooseneck to the mast. |
|
|
|
FIG. 3-16-Exploded view of a roller reefing boom assembly. The boom can be pulled aft on the gooseneck and rotated by hand to roll the sail onto the boom. When released, the boom then returns to its position on the gooseneck because of the pressure set up by the spring. The mainsheet fittings are secured to the tang at the aft end of the boom which is secured with the bolt slightly loose so the boom will rotate, while the tang remains stationary. |
 FIG. 3-17-A clew outhaul on a loose-footed sail The boom is slotted at the aft end for a sheave which allows the line to be lead to the underside of the boom where it can be cleated. A simpler type used on very small boats consists of merely a slot or groove in the end of the boom in place of the sheave. |
FIG. 3-18-A more sophisticated clew outhaul arrangement uses a line dead-ending on the opposite side of the boom (not visible) and running through a block shackled to the clew of the sail. The line then passes through-a cheek block on the side of the boom and to a jam cleat where it can be belayed. The sail can be secured to the boom with either a bolt rope groove or slides on a track. This arrangement has a built-in power advantage thereby allowing greater tension to be placed along the foot of the sail. |
FIG. 3-19-A CLEAT is a fitting to which a rope may be belayed. This metal cleat is fastened to the side of a mast to belay a halyard, and is a typical example of a cleat.
To be continued in the next WebLetter