catamaran from two outrigger hulls

[brooks]

In Bali i see many out rigger style boats used for fishing and the like. the boats have a hull and an outrigger. Would two hulls be better than one? IE get rid of the flimsy out rigger and replace it with a hull so that it is a catamaran. If any one has ANY ideas on this and why is is good or bad i would love to hear it. I am thinking about a boat for Bali's nearshore water and this is just an idea.
Thanks

Brooks

[HJS]

What do you mean by "better"?

hjs

[brooks]

1- better(more) load carrying capacity
2- Better stability with two hulls vs Hull and outrigger
3- better rigidity between out rigger and hull
4-ability to handle weather that would make an outrigger struggle.

3 times i have had an outrigger snap off. some was weather and some was poor maintenance. I would like to avoid this and have more flexibility with the hull or hulls

thanks

Brooks

[gonzo]

Those outriggers handle rough weather and surf nicely. They have done so for thousands of years. You would increase the displacement which would mean you need more power to move it. Also, instead of one person with a paddle steering in the surf, you need two in sync or a rudder system. They developed into a very efficient design and construction through the ages. I believe that some modifications can be good, but you are talking of a complete different design.

[TeddyDiver]

3 times i have had an outrigger snap off.
That would be even more demanding task with a cat to keep everything together.. instead how about smaller outrigger:rolleyes:

[peterAustralia]

you can do it if you want to, but think it would be a downward step, not an upward step.

If you want better load carrying ability, suggest find a bigger outrigger canoe.
Safety, the outriggers are small so that they impart only modest loads. The loads that they can exert are limited to their displacement, which is small.
With small outriggers, relatively light crossbeams are required.

If you go for a cat, you will need a set of very strong crossbeams and connectives to cope with the very large stresses and loads on the structure. You can imagine that as one hull bow enters a trough and the other goes into a wave, the very high twisting forces exerted on the hull and connectives. So yes it can be done, but you will be required to build strong crossbeams and attachments.

Outrigger canoes, well with these the Polynesians colonized the pacific from New Zealand to Easter Island to Hawaii, and every island in-between. Generally they had boats with a single outrigger, though the large catamarans (with very narrow beam) were used on some voyages, they werer in the minority.

To improve on safety on your traditional bali outrigger, you could add some modern contraptions, like a GPS, marine radio, echo sounder, satellite phone, small auxiliary outboard (eg 2hp for when no wind), modern foam flotation, high quality water containers, modern charts, life jackets, tinned food for emergency, flares, epirb. My guess is that most of the bali outriggers go to sea without all this.

These modern contraptions should assist in safety. The traditional layout is not all bad. The chances of surviving a journey with all this safety equipment added should be excellent.

peter

[peterAustralia]

i just read the bit about the outrigger snapping off,

Maybe you can make a set of improved outriggers, with modern materials but of a shape that is very similar to the traditional type. The modern resins and fiberglass chance of rot should be reduced.

[Chris Ostlind]

Go ahead and do it, Brooks. You'll have a blast.

At the Newport Aqauatic Center in California, we regularly lash together two, full-size, six-man boats in a cat configuration. The setup works really well for anybody who is unsure of getting into a regular outrigger boat, be they older, or very young.

The boats, when setup like this, paddle just fine, still show a decent turn of speed and are absolute bomber safe.

Doing this will give you a wider latitude of possible uses and the boats can always be returned to the basic configuration in just a few minutes.

[AnalogKid]

Outrigger canoes, well with these the Polynesians colonized the pacific from New Zealand to Easter Island to Hawaii, and every island in-between. Generally they had boats with a single outrigger, though the large catamarans (with very narrow beam) were used on some voyages, they werer in the minority...

peter

Peter, my reading on the subject are the exact opposite. Double hulled canoes, often arranged with very little gap between the hulls (which were not necessarily of equal size) were the norm for long voyages. Single-hulled outrigger canoes were for coastal trading and fishing, being easier to build and lighter to launch and beach. The prevalence of single-hulled outriggers and sailing proas today is largely attributed to settled populations 'forgetting' the skills and designs to build larger, migratory craft. Larger vessels are most absent from the larger land masses (Hawaii and New Zealand) where the population were more confident of not wanting to leave again. It's a theory backed up also by the secretive nature of the proa builders of Kiribati today.

Andy.

[peterAustralia]

hi

interesting argument, possibly a degree of truth in that, about losing knowledge base when colonization is no longer an issue.

My understanding was that single hulled outriggers were (are) considered safer than double outriggers and safer than catamarans. It is also my understanding that the traditional catamaran of Tahiti was in the process of being replaced by the Ndura at time of first European contact. The Ndura being a large craft with an outrigger about 60% the length of the main hull.

My understanding was that the Tahitians were being influenced by the Proa designs from Melanesia.

However whichever idea is true, they were all very impressive. Must have taken some real guts to travel half an ocean in a small boat kept together with coconut husk fibers.

I make no claim to what is categorically the best craft, merely to relate what I have have read. Life is too short for silly arguments.

In big news for me I have 10 days off between Christmas and new year,,, think I will go sailing in my tacking outrigger canoe...

peter