Hi

"but they would be too light and it would go against the program of the
boat: eays to build and maintain with locally available materials and
skills."

This is proberly the core issue but please remember how skilled
craftmanship you se from these contries, --- My attitude is ofcaurse
that to further gain and make a relevant promise of a future that work
, these skills shuld be put into digital rather than staying with
methods and tools that was relevant 70 years ago. Now please exchouse
I repeat but 3D-Honeycomb form any shape, it even prove easyer presing
a button to get the intire framework assembly, than adding rib after
rib polyline or spline , translate this into somthing that in it's
aproach is the same Oak rib as you seen in ships from the 17' century
---- it even is easy for the designer, the one who shuld draw eash
frame stringer and rib, to have the computer calculate everything down
millimeter accurancy and in only one material sheet material , as this
also make the same easy foundations for a house --- now do you read me
?

Per Corell

After recent Tsunami disaster, toying with the idea to
help make hand /sail/outboard moter powered fiberglass fishing boats of
standard 30 feet length.

Some FAO documents on the subject:
http://www.fao.org/documents/show_cd.../W7260E/W7260E
00.HTM
http://www.fao.org/DOCREP/003/T0530E/T0530E00.HTM
http://www.fao.org/DOCREP/003/V9468E/V9468E00.HTM

Paolo

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.

As I understood what you were saying is,

When the CNC machine cut templates by CAD drawings mesh together, a
rigid shape boat becomes available already!... and there is no need to
have a separate mould,much of drudgery is taken out of forming the hull
shape, both the inside and outside shapes are formed and are ready to
be filled in and spruced up. It is a logical but advanced continuation
of plywood laminating method. Right?

This 3D honeycomb technique appears highly productive and cost
effective, irrespective of how many boats have so far been made or not
made.

Regards

wrote:
Hi

I must agree that I do not believe 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.

Hi

The CNC is the sideeffect the gain but youdo not need a CNC mashin to
cut the framework , it can be cut with quite tradisional tools or
mashins.
The plans can be plottet on paper in full size and in the simplest way
to make the boat, you simply spray glue the full scale plans ontop the
sheet material and cut from the lines on the drawings, ---- the pieces
will fit together perfect.
But the technology I point to is the simplest and cheapest way to
establish a real digital production, the N.C. cutter is the cheapest
N.C. controlled equipment on the marked, but there are much more to it
--- the concept is a compleat change of aproach it make 4 boats at the
same time as 1 with the old methods.

Ontop there are the thing about materials this method ask only one type
of material sheet material. Where other methods ask 20 different
profiles knees , hangers, stringers nuts and bolts ----- again with the
3D-Honeycomb you do not bend any piece of the ribs or frames , when cut
flat they slide together to form a reliable and in terms of design and
projecting very rugid and simple structure ; again you do not bend one
single piece and pieces when cut fit perfect together, this is very
different from the time comsuming aproach you se in other methods where
fiddeling and bending acturly is a big and time comsuming part of it.
With this method you get the boat in the drawings. and pieces can be
made everywhere are easy to transport before assembling .

Now did I point to the fact that in easy terms and in a way everyone
can understand, computer design and cheap digital projecting make sense
and point to other progress such as how to build a house at a third the
cost so strong it will resist an earthquake , but if this issue
interest you please check the hundreds of structures to explain the
3D-Honeycomb concept, --- how also in architecture the 3D-H structure
offer a new aproach a new way to build and project a building by
offering the basic structure in a way that promise the new jobs and the
cheap strong new houses.

This concept do not deal with rebuilding with dirtbags, barbed wire and
mud --- it promise the new technology at a state everyone can
understand just by looking at it, it acturly make the computer work
where today's design and architect applications mainly is about making
a digital account , it is so different from the old methods and still
it only build ontop and offer just what you can emagine , but in a way
you can call digital.

P.C.

Narasimham wrote:

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.

I think you first have to define the boat and it's mission a bit better
- hand (paddle/oar) powered will have to be smaller than sail or
outboard power. How much cargo (fish) will it carry? How fast does it
need to go?

Rigid PU foam is o.k. for insulation and flotation but not structural
purposes; it is too brittle and weak.

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

Hull shape will depend on whether it will be a planing boat (fast with
outboard power) or slow (sail or human powered)

If you hire a naval architect they will define the shape of the hull and
the construction method. If you are building more than a few boats, a
female mould (concave shape) is the only way to build efficiently.

You may also be able to purchase stock (premade) plans from a plan company.

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?

Yes, Lloyds, DNV (Det Norske Veritas) and ABS (American Bureau of
Shipping) are the big ones.
But for a third world project they will be costly and probably not
worthwhile or needed.


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?

It depends on what the existing shapes are and how heavy they are built
and where the weights are located - too complex to give a simple answer
here.

For a physics picture of stability:

1) Is metacentric height a parameter to assess stability?

Yes - higher GM means higher static stability

2) Draft. On what factors is load-depth of immersion relations
established?

The shape of the waterplane area (cross section of the hull) determines
how much it will sink at a given draft.


One thought - in Mexico fisherman changed their style of fishing boat
over the past 20 years or so. Initally they used dugout canoes with
paddles or simple oars and stayed close to shore.

Later dugouts had small outboards added, and were sometimes replicated
in fiberglass.

Then the "panga" appeared, a very shallow deadrise (shallow V shape
hull) about 24-26' long. It is built in fiberglass and typically uses a
48,55, or 70 HP outboard motor. These boats are very seaworthy and
often venture offshore about 50 miles, catching up to about 1 tonne of
fish before returning home at slower speeds. Gill nets are the most
used fishing gear. These boats are beached at the end of the day or
anchored just off the beach. They are built in solid fiberglass with
some wood for rubrails and seats etc. They look like this:

http://www.panga.com/pangagallery/pangamex.html

I think they are a good solution to Mexican fisherman's needs but the
government had to offer low interest loans to allow the fisherman to buy
the motor and boat.

Good luck.

Evan Gatehouse

Narasimham wrote:
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

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.

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.