The Hina

The Bora-Bora is a catamaran of the type Hina, a so-called Classic design of James Wharram. Wharram designed a few catamarans according to the Polynesian model between 1957 and 1976. Nowadays James Wharram is still active designing and delivering building plans for catamarans. The whole wooden Hina – the predecessor of the current Tiki 21 – is about 6,40 metre long, 2,30 metre in width and 0,70 metre high. Neither of the two hulls has a keel or lee board because of the drift- and verlijer delicate. Both hulls possess a twist rafter model and are structured with multiplex board glued together as a frame “wagers” lengthways and “leggers” and “spanten” in the breadth. The hulls are held together with three robust beams. On top of this rest the deck planks. In each hull there is a heightened watertight hatch, which offers considerable storage for our gear. The weight of the Hina is substantial making somewhat difficult to move for the four owners.

Mainsail
The mainsail is a gaff-sail of 16 square meters made from mylar. Our mast is somewhat lower than most of the tower-rigged boats. At the gaff-rig the sail is attached to the gaff. A forked-joint is attached at about 2/3 of the height of the mast. The peak is hoisted with a rope that runs through a pully that is fixed to the head of the mast. Usually the gaff-rigg has four corners but because our gaff-peak is hoisted extremely high, the sail is almost triangular in shape.

Genua
The genua has a surface area of 5.5 square meters, is larger than a regular jib and therefore less wind- and leewardly. But because the bottom line runs further than the mast the foresheet has to be removed from the mast during navigation making it rather intractable.

Spinnaker
The oval nylon spinnaker sail is used when there is substantial wind. The asymmetrical spinnaker of de Bora-Bora is attached to a kluiverboom that extends out about 75 cm. from the bow. There is a further attachment at the top of the mast and at the romp. This sail is approx. 20 m² in size and provides the boat with extra speed.

Mast 
The two-piece lowerable mast is made of softwood and is approximately 7 meters high. The mast stands between 2 short cleats which have no supporting function. It remains in place due to the support of the standing and running rigging. The forestay and backstay run to the base of the mast ( about 2/3 of the total length) where the second part of the mast begins and the crossbeam is situated. The function of the crossbeam is to ensure that the angle of the headstay and the hulls does not become too small. 

Rudders
The hanged rudders, together with the sails, ensure navigation of the Bora-Bora. The rudders are attached at the stern and are operated with tillers. The advantage of hanged rudders is the large stearing effect due to being attached at the back of the boat. They’re also very easy to (dis)assemble.

Trailer
The Bora-Bora is transported on a made to measure metal trailer. This is unfortunately not constructed of rustproof steel. The action is simple. The trailer is placed between the hulls. Because the hulls are oval on both sides, two tubes can be pushed in the trailer. These tubes are placed in a hinged region which are attached to the chassis by pulleys and can be winched.

Tractor
We use a small caterpillar-tracked tractor to transport the trailer with attached boat to and from the water. It is a 30 HP, two cylinder diesel-driven tractor from the 1980’s. The Toselli has five forward and one reverse gear. It is steared by alternatively using the break on one or the other track. A hydrolic lift capacity is available.