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The Launching

The Paraw was named Sinalimba during the launching ceremony dated January 28, 2017. Sinalimba is a Subanon word for a mythical watercraft of the gods for journeying. Subanon are “people of the river” that inhabits western Mindanao, Philippines. In tribal performing arts, Sinalimba is represented as a swing where male dancers leaps onto the platform and moves with its momentum while dancing with the rhythm of gongs and drums ensemble.

Sailing this Paraw is like dancing on a swing. Dictated by the rhythm of the waves and wind, the crew has to move from side to side on the aka. The experience is very lively and a bit intimidating. It sails fast and rides comfortably in choppy seas.

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Bamboo

In my part of the world, bamboo is the most practical resource to be used as amas, spars, and mast. Fast growing, widely abundant, and ecologically sustainable. Every specie has its own favorable attributes, either for structural or plain aesthetic application.

This is the favorite material for outriggers because it floats and dissipates too much load by bending. Its longitudinal fiber is the perfect orientation for flexural members of a  watercraft.

Bamboo parts is inexpensive to maintain or replace. It last a long time, especially when used in saltwater environment.

During gusts, the bamboo spars and mast will absorb the sudden rush of energy by bending. It creates harmonic resonance to the entire boat. It can be annoying to some people but on the other hand, the vibration gives the helmsman a feedback on what’s coming up. The outrigger will either spring up to speed or spill the wind by submerging the leeward ama.

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Abaca Rigging and Lashing

A natural fiber indigenous to the Philippines has been the preferred construction material for lashing traditional houses and sailing outriggers. Highly regarded for its tensile strength and resistance to saltwater damage, it offers a sensible use in highly stressed components. Austronesian (Filipinos) sailors has been using it for centuries. Abaca is a perfect match for lashing and reinforcing bamboo.

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Building the Hull (Bangka/Vaka)

The conventional method of building a Bangka is to shape a log keel by carving out the bilge. Followed by the fore and aft stems, then the frames, gunwale, and thwarts . The hull side panels are the final pieces. The only part of the Bangka that wastes too much valuable wood is the log keel. The volume of wood chips that was taken out, could have been put to good use as other parts of the outrigger.

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In my opinion, strip planking method is an efficient way to use recycled wood or commercial sized lumber. It is a satisfying approach to highlight the wood grain other than plywood.

Weight & Balance

Some technically inclined people hate low volume amas because it dives into the water when the sail takes too much wind power, and loses the opportunity to maximize speed. So they tend to attach higher volume amas, considering the additional weight it requires for all related parts (crossbeams, spars, and mast). Austronesian sailors simply add additional crew during windy days, to walk or crawl between the ama and vaka. No need to complicate the watercraft.

A 125mm diameter x 6m long bamboo ama has a buoyancy force at around 70kgs, located at 2.70m away from the mainhull centerline. A 75kgs person standing directly on top of the ama will submerge it instantly. If the same person will sit on the aka at about 2 meters away from the mainhull centerline, you have a balanced “moment” loading. That is for a boat at rest.

In reality, when the outrigger is underway, the amas submerge into the water very often no matter how good the crew is. When it dives, it always springs back up because of increasing pressure head underwater and hydrodynamic flow on the turned up front end. The key for this kind of outrigger is speed, because it is directly proportional to stability.

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Don’t get me wrong, these outriggers are not built for racing, these are ordinary workboats for everyday fishing and inter-island commute. It is a “grassroots” watercraft that anybody can build at their own backyard.

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