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

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/

On 15 Jan 2005 08:49:10 -0800, "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?

If the density of the new hull materials duplicates the wood, the
capsize behavior won't change. If the new hull is thicker or thinner
but weighs the same overall the behavior still won't change enough to
notice.

For a physics picture of stability:

1) Is metacentric height a parameter to assess stability?

Yes, it is one factor.

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

The volume of the immersed part of the hull displaces the weight of
the vessel in water. That is what displacement means.

HTH



Rodney Myrvaagnes NYC J36 Gjo/a


Capsizing under chute, and having the chute rise and fill without tangling, all while Mark and Sally are still behind you

wrote:
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 proposes a new building method
developed just to overcome some of the real troubles with ships
building and developed to offer a hull at a third the cost, in modern
seaworthy design , three times the strength of traditional
construction
methods and actually using the computer for the lofting and cutting
of
the only material needed for these designs.. sheet material.
The plans are free and cover traditional small dinghies up to ocean
going combined sail/speed boats. Please notice that as the plans are
CAD drawings, you can alter the designs by up or down scaling the
entire drawing and from a 12 meter heavy speed boat ,end up with a
very
attractive and practical hull for a reliable and safe working boat.
A traditional boat of same size simply needs ribs or frames even in
the
building process, so you can fit the unfolded panels onto something
that
show the shape of the craft and act as substructure ---- with these
crafts. The frameworks go one step further, as they are arranged in a
3D
pattern that make each frame to be supported by all others, providing
a
much stronger hull ,leading to a building technique that makes the
hull
as a thick shell of frames forming a honeycomb structure that is
covered
with the paneling end up as a most rigid construction where sheet
materials are the main building material, where nothing in the
framework needs bending but is cut from sheet materials steel or
plywood.

These are most exciting 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 actually 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 guarantee of the hull given in the
plans,
the stability is better than what Lloyd ask. An option to foam
fill the honeycomb cubes promises an unsinkble hull. You
can cut a hole in the back and place a big in- or out- board thru an
engine
well__after the hull is built and even before you have chosen the
engines.

Check the slideshow that shows 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, pre-made glassfiber 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 other 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 half the trouble
building;

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

Best regards
Per Corell
Boatbuilder CAD expert

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

Thanks a lot for the elaborate reply. I have now before going through
groups a few questions,(no prior knowledge of naval architecture).

It appears that you have planar intersections of a hull surface in 3D
supplied as template drawings. When made, laminates can be fitted
together in a rigid curved framework serving dual purpose.. as a mould
and also as the core of sandwich boat after inner skins + resin are
laid and cured. Right? You supply the drawings, not the product and it
suits fine.

1) If you scale up the hull size of the CAD drawings, then you are
producing a geometrically similar boat hull, but how about the
stiffener sizes, thickness of skin laminates? Would scaled up
dimensions of stiffeners (bulkhead and hull fiberglass cloth or chopped
strand mat thickness dimensions) be indicated in mechanical design
charts?

2) Are displacement/stability parameters easily calculable by a formula
or design chart for each scale ratio?

3) How are boats made this way be certified for sea-worthiness?
Regards.

Here are some links to local fiberglass ocean going commercial fishing boat
builders. You might try emailing them.
http://www.peiboats.com/
http://www.huttboat.ca/
http://www.fourportsmarine.com/
http://www.magnamarine.com



"Narasimham" wrote in message
oups.com...
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

If you go to the boatdesign.net forums, there are active threads concerning how
we can help in that area.
Try he
http://www.boatdesign.net/forums/forumdisplay.php?f=26

Steve
Stephen C. Baker - Yacht Designer
http://members.aol.com/SailDesign/pr...cbweb/home.htm

Hi

I am a danish boatbuilder I build and design from experience and realy
none of my boats ever proven wrong, ---- the rules about materials is
easy you can find these easy a boat this size ask this thickness of
paneling and this amount of frames my buisness is true new building
methods and design.

The 3D-Honeycomb method offer a boat at a third the cost, much stronger
in construction and if you care look into detail in the design, also a
boat build much faster and one more very important issue ; the
materials do not need to be bended everything also the assembly
framework are cut from sheet materials.

A boat is structure and panels, this structure are among the most
efficient as it involve develobment in digital tools in understanding
digital tools in using the technology of the future to replace what I
learned being a boatbuilder and what I scrapped measuring it up against
the new tools .

Materials like sheet material ask only one production line where
tradisionaly you need several productions to different types of beams
profiles, fittings nuts and bolts, here there are only sheet material
that form any round or square form, ready to be covered with the
surface digitaly unfolded from the same 3D model that shape the
framework in exact measures.

The full-scale plans must not be scaled unequaly but to cirtain degrees
, a 7 meter can be scaled to 10 meter but ofcaurse not to 20 meter.

Now this is my ansver to you, for the Bolger fanatics I will say, that
unless you want the fishermen to make their bread from boats made from
scratch shut your mouth,.

Best regards, ---- the best it can be in honor of a proud old craft.
Per Corell
Boatbuilder
Copenhagen Denmark

Just as a caveat I don't believe that Per has any actual boats constructed
with his method.

--
Andrew Butchart


"Narasimham" wrote in message
oups.com...
wrote:


3) How are boats made this way be certified for sea-worthiness?
Regards.

You might try talking with the fishermen in the area since they have long
experience of what shapes work and which ones don't work well for their
waters. Then work from there.

Brian

Hi

Andrew maby you shuld join the Bolger crowd and suggest an elegant
Elefant, guess you and the other crowd acturly never reached the
hangover supporting oldfasion design pieces of offcut plywood and now
as the best skills you know, lead the bullying . Now you done well in
this group, being the outmost skilled craftmen in bullying and
harrassing displaying hate as the top social skill .

---------- Why do you spill your poison, wasn't it enough to take the
bread from some guy better skilled than the average Bolger fanatic ; am
I not all-american enough having a strange frensh name or are your ass
simply about to burn from anger that now real skills must show it
value.

Go suggest a Bolger design and laugh the ass out your pans, destroy the
reputation of anyone who dare say have visions and master the new
tools, but Andrew I build the old way, I even have a good reputation as
boatbuilder and you dryass crowd only have a reputation as dryass
usenet junkey's allway's on the lookout for somone to harras somone to
bully .
---------- Somone who think boats shuld not be build from scratch
plywood leftover.
You crowd allway's hated the skilled ones didn't you.