I am looking for multi-purpose multihull with some special
characteristics:

-Low cost (less than $5000) to build (or buy second hand if such a
design exists)

-For lagoon use only

-As large as possible, it must have a 'yacht' feeling in terms of
stability, so fairly deep hulls, up to maybe 40 feet long

-No cabin or sleeping space required, just a trampoline or plywood deck
structure on top of two glassfibre hulls

-No rigging required (this is where the expense normally is), i imagine
using an outboard motor to get upwind, and a kite to get downwind
(see here for my experiments with this
http://www.beachbreaks.co.za/hobie-kite1.aspx )

Do you know of any suitable designs which may exist?

Thanks
Matthew

wrote:
I am looking for multi-purpose multihull with some special
characteristics:

-Low cost (less than $5000) to build (or buy second hand if such a
design exists)

-For lagoon use only

-As large as possible, it must have a 'yacht' feeling in terms of
stability, so fairly deep hulls, up to maybe 40 feet long

-No cabin or sleeping space required, just a trampoline or plywood deck
structure on top of two glassfibre hulls

-No rigging required (this is where the expense normally is), i imagine
using an outboard motor to get upwind, and a kite to get downwind
(see here for my experiments with this
http://www.beachbreaks.co.za/hobie-kite1.aspx )

Do you know of any suitable designs which may exist?

Thanks
Matthew


Many ideas exist, one will be your favorite. Here's mine.

I had fun this weekend at the cottage with a design for dock floats
using old barrels and a clipless banding machine made by TITAN, lent
for a "demo" by a local packaging company.

Got a bunch of cedar planks, chamfered the edges 12 degrees, wrapped
the barrels in planks and steel band strapping. Made two pontoons
10' long from 3 barrels each, and a foot long flooded space between
the barrels, -bait bins? Might be able to make it all watertight
without too much fuss. Realise I could turn out pontoons as long as
required, by just adding barrels, staggered planks and banding. So
could you.

Materials cost, per 10' float: 3 barrels, at 15 bucks each, 28 each
5 foot by 6" by 1" rough cedar #2 ROM boards, bought surplus by the
pallet at a mill, cost uncalculated, say 20 bucks, 64 feet of
banding, hardly worth mentioning, stainless steel would cost more.
The banding machine costs 1200 bucks. Available for rent, or demo,
or employee training, even buckshea.

Made 'em in the yard in a day. Rolled them down the mountain to the
beach, almost singlehanded. Stove in one plank on a rock after the
float flipped end over end. Replaced it in 10 minutes by cutting the
banding and rebanding the float in the water. Assembly is fun, using
spanish windlasses, which are also required for partial dissassembly
and repair.

They are afloat now, waiting for wakes and rust to determine MTBF.

They are modular floating dock parts, able to be dissassembled and
beached easily, to avoid winter ice.

I am considering mass production using fence wire and staples to
speed assembly.

Just another method, eh?

There is a secret for the deck attachment and suspension details, as
yet undeveloped. Ask pretty and I'll let you in on it. It includes
keels and hydrofoils. It may yet sail.

I am a little afraid it all might wriggle itself apart in the water
with heating and cooling, etc. I may edge lock the boards with
finish nails or something.

Terry K