building a cat for the tropics

[AdventureWorld]

I want to build a 45'-55' sailing catamaran for commercial use in SE Asia.

Unlike most catamarans I want one with an open deck plan (saloon/galley located in hulls) to create much more usable deck space and air flow.
also under the impression removing the complex saloon/galley mold would greatly reduce costs

-sailing rig
-twin diesels
-grp or plywood

set it up for day sailing and mellow coastal cruising

I would look for a used vessel but you don't see many of these layouts in SE Asia.

so what would be the most economical way to go about this?

find some damaged or unfinished hulls? complete new build?

The reason I write 45'-55' LOA is because I have the understanding the hulls wouldn't be the expensive part, but all the other kit would be.

As well as the best way to go about it, what do you guess a project like this would cost?

as well as any suggestions on lowering costs would be greatly appreciated.

Cheers

[AdventureWorld]

[belizesailor]

What kind of commercial use? Day sails? Extended charters? ...


Take a look at the larger boats in the Wharram Pahi line:

https://www.wharram.com/site/profess...designs/pahi52

[AdventureWorld]

Originally Posted by belizesailor

What kind of commercial use? Day sails? Extended charters? ...


Take a look at the larger boats in the Wharram Pahi line:

https://www.wharram.com/site/profess...designs/pahi52

I like the Wharrams! the ones i've been seeing on the market are way overpriced tho.

mostly interested in day trips, but would like be able to offer overnight to five day charters as well.

thanks for the suggestion

[belizesailor]

Lots of open bridgedeck cats in the day trip trade. Like those built by Gold Coast:

http://www.goldcoastyachts.com/Comme...g/CS-index.htm

Maybe you could find a used day tripper, but nothing in that size range will come cheap...unless its in really bad shape.

[DerekKelsall]

Originally Posted by AdventureWorld

I want to build a 45'-55' sailing catamaran for commercial use in SE Asia.

Unlike most catamarans I want one with an open deck plan (saloon/galley located in hulls) to create much more usable deck space and air flow.
also under the impression removing the complex saloon/galley mold would greatly reduce costs

-sailing rig
-twin diesels
-grp or plywood

set it up for day sailing and mellow coastal cruising

I would look for a used vessel but you don't see many of these layouts in SE Asia.

so what would be the most economical way to go about this?

find some damaged or unfinished hulls? complete new build?

The reason I write 45'-55' LOA is because I have the understanding the hulls wouldn't be the expensive part, but all the other kit would be.

As well as the best way to go about it, what do you guess a project like this would cost?

as well as any suggestions on lowering costs would be greatly appreciated.

Cheers

Hi,

Over the years we have designed many open b'deck cats. We can supply a design and THE most efficient build method - KSS. Contact <derek@kelsall.com>for discussion/quote. Basic materials are pvc foam and glass/polyester skins, which are similar cost to ply when the large wastage of ply is taken into consideration. Happy boating, Derek.

[boatman61]

I'd forget the Pahi.. they're crap compared to the Tiki.. this is a 46ftr and you do not have to build the deckpod if you don't want one.. sail and look much better than the ugly Pahi.
You can get the Study Plans and contact local boat builders to see if they can build one.. or do it yourself.. one bit of advice.
Import your epoxies, don't buy local products.. SP or West Systems are preferred.

[billgewater]

Some tropical issues.
The sun is a killer. Ventilation is a killer. Rain can be a real serious issue.
Many cats designed for the charter market have some serious non tropical features. The classic one is sloping large glass/acrylic “windows” across the front of the vessel. It makes the vessel into a classic greenhouse. Light pours in, coverts to IR inside and cooks everyone. Sloping glass frontages may look good but they can be a disaster in the tropics. (Some approaches can be seen in the stepped slot covers in the Leopard line up and the rather eye catching but not cool looking vertical shaded windows seen in some other designs.)
Ventilation needs to be really very carefully thought out. Reliance on deck hatches is not smart thinking as they can’t be readily used when it is raining. Just when you have hot humid air inside. Plus your customers fall through them and then sue the bejesus out of you. And these deck hatches cost a motsa … and invariably leak, or are left open in the rain.
So in MHO you should be seeking very large shade areas. Careful avoidance of the greenhouse effect and extremely good ventilation that works in the pouring rain.
These can be achieved if you spend the time designing. E.g. by placing downward facing covered vent slots at the highest place available you can allow accumulating moist warm air to safely self-ventilate out even in the rain. (As it rises to the highest level being less dense than cooler air which comes in to replace that rising air.) These vents are dirt cheap to make or buy and require no attention at all. But not a good idea in very cold environments unless you put a closable cover inside the vessel.
These passive vents also help prevent mold.
Avoid vertical or sloped windows where possible. Try to get good visibility by having the aft deck at a higher level than the bridge deck floor. This means that with the crowd on the aft deck they can all see over the “roof” of the bridge deck and remain in the shade and be ventilated as well via the slot formed. Maybe a smaller bridge deck section with a much longer covered raised (say 40 to 60 cm) aft deck. Another variant is to simply have a full length covered deck with a wide cover. i.e no separate enclosed bridge deck at all. Breezy, shaded but not great in driving rain.

The Seawind cats may be a bit small but the larger ones have totally open spacing from the deck into the bridge area. The aft area totally covered. Seawind also produce a charter cat with no bridge deck cover at all. Great for night charter! Seawind cats have been used for charter around Darwin which is seriously tropical. They also have very simple effective outboard propulsion systems. And they sail well. Simple and largely manageable by guests leaving you to regale them with tall stories etc.

[captlloyd]

Originally Posted by AdventureWorld

I like the Wharrams! the ones i've been seeing on the market are way overpriced tho.

mostly interested in day trips, but would like be able to offer overnight to five day charters as well.

thanks for the suggestion

Hmmmm, way over priced for you or everyone. What kind of budget are we looking at here ? Are you going to build yourself ?

[ZULU40]

Originally Posted by AdventureWorld

so what would be the most economical way to go about this?

Modify an existing design in need of refit

[belizesailor]

Originally Posted by captlloyd

Hmmmm, way over priced for you or everyone. What kind of budget are we looking at here ? Are you going to build yourself ?

My Q also, what is your budget for this venture?

Large cat and inexpensive are mutally exclusive terms unless you plan to build with pool noodles.

[Bean Counter]

1992 Fountaine Pajot Marquises 56 Sail Boat For Sale - www.yachtworld.com
there is a project

[boatman61]

Not necessarily that expensive if you build in SE Asia using skilled local labour.. there's still great traditional carpenters out there at very cheap rates compared to the West.. back in the 80's I had the idea of starting a Wharram building project in Karachi.. then if it went well take it to market..
Found the skilled labour no problem, good hardwood timber was plenty and cheap for the frames and keels so started on a Hitia as a test run.. where it came unstuck was the quality of the ply and the epoxies.. the one had to many voids and the epoxies available locally back then were undated and unpredictable.. some would cure too fast, some would never cure, no matter how careful you were in measuring the mix.. ended up packing it in.
However.. if you have reasonable enough funds to import the sheets of Byunzeel marine ply and fresh epoxies fillers etc from Europe you could build a unique and beautiful 46ft Tiki pretty cheaply.. mast are wood or alloy tubes so nothing complicated.. sails are simple boomless gaff wing with sleeve to go round the mast.. simple to make locally, rigging use's cord instead of bottle screws so simple to make.. beams are lashed to the hulls so no complex building techniques..
Its worth a look.. the study plans provide a full list of materials needed for the build so pricing is easy.. just need a bit of beach front land and a lean to for keeping the sun/rain off as you build.. and the 'Stitch and Glue' method is so much easier and faster than the old traditional Wharram build.