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Narasimham · Guest

Am mechanical engineer with a composites background presently residing
in south India. After recent Tsunami disaster, toying with the idea to
help make hand /sail/outboard moter powered fiberglass fishing boats of
standard 30 feet length. Raw materials .. chopped strand mat,
fiberglass cloth, polyester resin and rigid PU foam are commercially
available locally, as is semi-skilled labour who could make boats to
pre designed drawings.

Can someone help to guide in the following ?
Shapes: Are drawings available on net? or on payment? What hull shape
is better? U? Flatbottom?

Do Lloyds or other certifying agencies based in Europe/US have a
branch or mechanism to test and certify marine craft after fabrication
and testing when involved right from beginning stages in India?

If existing wooden hull shapes are duplicated but replaced by solid
fiberglass laminate or polyurethene foam (closed cell to keep out
water) sandwich, would it serve the purpose with stability resisting
wave forces with adequate margin before capsizing?

For a physics picture of stability:

1) Is metacentric height a parameter to assess stability?
2) Draft. On what factors is load-depth of immersion relations
established?
Hope not a tall order. TIA for all helpful tips.

G.L.Narasimham

Guest

Hi

I will point to a Yahoo group where you can find free/download design
of various sizes and different types of construction. What is
interesting about the site is that it progress a new building method
develobed just to overcome some of the real troubles with ships
building and develobed to offer a hull at a third the cost, in modern
seaworty design , tree times the strength of tradisional construction
methods and acturly using the computer for the lofting and cutting of
the only material needed for these designs, sheet material.
The plans are free and cover tradisional small dinghies up to ocean
going combined sail/speed boats , please notis that as the plans are
CAD drawings, you can alter the designs by up or down scaling the
intire drawing and from a 12 meter heavy speed boat ,end up with a very
attractive and practic hull for a reliable and safe work boat.
A tradisional boat of some size simply need ribs or frames even in the
building process, so you can fit the unfolded panels onto somthing that
show the shape of the craft and act as substructure ---- with these
crafts the framework go one step further, as they are aranged in a 3D
pattern that make each frame be supported by all others, providing a
much stronger hull ,leading to a building technike that make the hull
as a thick shell of frames forming a honeycomb structure that covered
with the paneling end up as a most rugid construction where sheet
materials are the main building material, where nothing in the
framework need bending but is cut from sheet materials steel or plywood
..
These are most exiting designs in terms of ease of building while the
plans in full-scale show each detail, the hull consisting of a thick
shell with the perfect framework underneath offer a ready hull where
most time comsuming details are removed by design, --------- The
full-scale plans can acturly be spray-glued onto the sheet material
chosen for panels or framework and cut from the lines on the drawings
directly for perfect fit and a garentie of the hull shown in the plans,
the stability are better than what Lloyd ask and an option to foam
fill the honeycomb cubes promise a hull unable to sink one where you
can cut a hole in the back and place a big in-outboard thru an engine
well --- after the hull is build and before you chosen the engines.

Check the slideshow that show just a fraction of both old and the new
3D-Honeycomb based designs, anyway Cyber-Boat offer free download of
true 3D modern designs _and_ the unfolded panels plus building jig and
framework assembly, and any material you need, is sheet material of
your choice ; that be steel, premade glasfiber sheets with one side
nice turning outside making the finish as the first thing and the
framework as somthing you can cover with mat and resin and just leave
there using it first as building jig and later as permanent honeycomb
framework.

Now please check the site, there are several orther groups with
designs, you will find the links at the main group's homepage --- Btw.
check a search about 3D-Honeycomb as the method also build a house at a
third the cost four times as strong and only halve the trouble building
;

http://groups.yahoo.com/group/Cyber-Boat/

Best regards
Per Corell
Boatbuilder CAD expert

http://home20.inet.tele.dk/h-3d/

Rodney Myrvaagnes · Guest

On 15 Jan 2005 08:49:10 -0800, "Narasimham" <mathma18@hotmail.com>
wrote:

Guest

Hi

I must agrea that I do not belive that glasfiber and resin is the only
solution.
I love to use Epoxies and know that a glasfiber boat offer the top of
what boatbuilding achived but I do belive more in other methods and I
think that sheet materials is a better alternative even as ready made
sheet materials cut after Digital projecting, --- . Still I do belive
that a combine of methods, like how you already se bigger glasfiber
paneled boats build with wooden frames , but why not take it a step
further so the boat only cost a third and is four times as strong, and
the builders start using actural digital tools not rewritten old
methods. Personaly I find epoxies and polyester to valuable a source
and the need for digital manufactoring more important , even in space
industrie the best would be metal not epoxy, but anyway if this is
about efficiency what\s wrong with pre hardened glasfiber sheets pre.
cut to form the framework assembly ready cut panels , and then build up
inside that, ---- premade glasfiber sheets already offer one smooth
side, why spend the time making an expensive plug to make a form if a
new technology offer a much more promising aproach. Why not focus on
sheet materials as that cover plastic aswell as metal and steel or
plywood.
Digital options as we se them today, is rather about making an
expensive plug with an expensive 3D router just to support a maby worn
out technike ,rather than using and expanding the real digital options.

With 3D-Honeycomb my attitude is, that now you have the full freedom
forming and a garentie for the strength , but it also is a compleat
other world, than just doing what else could be made by hand anyway,
realy you don\t use a 3D router for that and it seem that a simple 2D
N.C. cutter prove much more efficient forming the pieces for an
assembly.
Today\s design and architect programs are not about shaping the form
and generating the assembly but make a neat account, an account just as
70 years ago , now if we aks new solutions and new jobs it is my belive
that this ask a change in perception . We still translate the old
methods into computer code and ask a 3D router to router out the plug
to make the form so we stay with boatbuilding as how that is today,
maby a change in the way to build a boat or a house is what will bring
the jobs and the nice boats and houses at a third the cost four times
as strong as that ask digital tools.

P.C.

Evan Gatehouse · Guest

Narasimham wrote:

mason · Guest

I failed to enter my message yesterday. I'll try again. Thirty or so
years ago the Constant Camber method of cold-molding boats was invented
by some multihull designers who were working for the UN Food and
Agriculture Organization and the World Bank to help Third-World
fishermen repatriate their boatbuilding, and do it with indigenous
materials mostly, and return to easily-propelled forms that might
relieve these fishermen from the need for imported motors and fuels. In
general, though the method is great for building certains families of
forms with any wood you can slash into veneers, and only the glues
needed to be imported, the projects in various parts of the world
generally faltered: fishermen didn't want to go back to oar and sail,
and corruption carried off the money. I don't know who builds in
Constant Camber now except a for an occasional big multihull. And
myself. I have built about 66 small CC rowing and sailing craft, canoe
bodied, and the method is marvelously efficient for such boats, cheaper
than making equivalent boats out of purchased flat plywood, and
resultes in light, strong, durable, low-maintenance boats, easily
driven. But to get to the important part of this note, it's just a
warning against trying to deflect the fishermen from their customary
boat types. It does seem to be one of the best places to put aid: into
restoring the fishing fleet; but I don't know why it can't be done real
fast with brute money and available boats that are much like the ones
we've all seen trashed by the wave. There must be many with this
impulse to help, and I have assumed that people much more knowledgeable
than I are on the scene already, bless them.

Guest

Hi

You write it yourself "thirty years ago or so".
But this is not what will spark a fast rebuild it will not make the new
jobs it is old technikes what do you expect.

Now about my role in this please read the following text, please ask
yourself what ansver is relevant, protecting the dead profets hounting
the real visionary ;

"Then one who studied the law come to him and ask --- not to get an
ansver but to justify himself, Guess we all know this kind of questions
they ask only in the hope that the one who ansver, will ansver in a way
that will make him "impossible" in the minds of those who listen, or by
twisting the words make the ansver silli ---- and if he do not ansver
or ansver somthing they don't expect they will display a head shaking
attitude
saying "there you se" ."

In this group you se the ansver in this tread, this is not about
helping those who suffered to make the new hope or create the new jobs,
to do that you must invest in the new options realise the digital tools
that is so different from old fasion building a boat or building a
house , --- now just wait , there will be yet another hatefull usenet
fanatic with just another filth ansver somone who will display the
social skills that is praised in this group.

P.C.

Narasimham · Guest

alex wrote:

Guest

Hi

I only promise that in 3,5 years the issue of rebuilding the structures
like boats and houses is already solved, then ontop come the gains of a
new technike at it's original form.
What can be acomblished in terms of beautifull buildings can't be
explained you don't need a naval architect for that, this requier a
designer, One that maneage to spell hell in small caps.

Auerbach · Guest

<per.corell@privat.dk> wrote in message
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