SHIPBUILDING 
You are standing now in the area that will show you the evolution in boats and shipbuilding through the use of different materials and techniques.
Sailing on rivers and estuary zones started in Northern Europe five thousand years before Christ .The first boats called “monoxyles” were first carved in pine trees , and later in oak trees in neolitic times. These oak pirogues were carved with what is known as the “fire technique”, then they were shaped with flint adzes.
In
the Bronze age, the boats became flatter and were sewn, which allowed
huger
loads to be transported. Two main tree species are commonly
used :
-
the oak tree ( or sometimes the beech tree) for the hull
-
and the pine tree for the
masts.
The
elm, the chestnut tree and acacia
are used for bent- shaped elements while the rudders are carved in
walnut tree.
In
Normandy , there are two traditional techniques for building wooden
boats
: clincher work and free board;
- Clincher works was inherited from the Vikings and their drakkars and has been
First the hull is made with the same technique as a roof , with boards nailed the ones over the others ; once the hull is finished and turned upside down, it is reinforced with thin ribs.
This
type of shipbuilding reached its peak at the end of the Middle Ages.
However,
this technique will be used in Normandy and in Sussex until the first
half of
the twentieth century for small boats such as
the doris ,the caique and
the English punt .
-
free board
:
This
modern shipbuilding technique is still used nowadays for traditional
wooden
boats . Less wood is needed, which is a good way of preventing the
deforestation
of the French forests .
After
adjusting the keel, the stem and the sternpost which are master pieces,
the
skeleton of the hull is built up , boards
are nailed on it the ones after the others .
This
technique allowed bigger transport boats to be built and it developed
the
sternpost rudder.
Then
the waterproof quality of the hull and the deck is achieved thanks to
the
caulking of the planks : the empty spaces between the boards are
stuffed with
stings of oakum and pitch (tar and mastic). Once the boat is at sea,
the wood
saturates and the water proof quality is now totally assured.
Building steel boats started in Dieppe in 1890 with the creation of a shipbuilding site called “Amblard” , which took the name of “Ateliers et Chantiers de la Manche” in 1912, and eventually became “ Channel maritime Industry” in 1988.
Until
soldering is developed in Dieppe in 1935, steel boats are made with
iron plates
Put
together with rivets on skeleton of
ribs and steel girders.
More
than our hundred workers are needed to build a thirty-two-meter -long
trawler.
Nowadays,
with computer-aided design and numerical controlled machines, shipbuilding
has
been modernized and consists in four
stages:
-
drawing and conception: models and plans are made in the mould
loft;
-
machining : the iron plates are cut out with numerical
controlled
blowtorches , then shaped and put into place;
-
pre-building : nowadays, a twenty-five meter steel trawler is
made of
five or six part assembled on the landing- place. Some parts may come
from other
shipbuilding sites( Nantes , St Malo)
-
The last stage is the fitting out and the motorization of the
boat. More
than twenty different corporate bodies work on the trawler six or eight
months
before it can be launched (
painters, woodworkers, plumbers, mechanics, computer scientists …)
Today,
more than one hundred years after the steel shipbuilding started, more
than
three hundred boats have been made in Dieppe and eighty people work on
the site.
Aluminium
is an alloy invented in 1886 from bauxite.
It
offers five advantages for shipbuilding/
-
it is much lighter than steel;
-
it is non-toxic for the fish stored in the hold;
-
it is non-magnetic for the controls;
-
it has a high mechanical resistance.
However,
as aluminium is very expensive, it is mainly used for small fishing
boats (doris
and trawlers)
The
“ Allais” shipbuilding site in Dieppe employs more than 20 workers
specialized in aluminium shipbuilding.
Composite
materials or polyester allows boat making in series.
The
economic crises which touched the fishing industry at the beginning of
the
80’s obliged to lower the production cost. Composite materials ,which
had been
used up to then for pleasure boats only, began to be used for 12 to 22
meter
fishing boats.
This
type of in series construction is made from a mould in which layers of
gel coat
, textile glass, carbon and resin are superimposed
.
Composite
materials offer 4 advantages:
-
The cost and time for making the boat are reduced;
-
It is free from corrosion;
-
It is extremely light; it can be easily maintained and repaired.
Oars and
sails have been used since Ancient Times, as can be seen on many
bas-reliefs.
Indeed,
an oar is the extension of the arm and the hand.
There
are four different types of sails:
-
The square
sail dates back to
Ancient times in Northern Europe and was in use on Viking ships as well
as on
caravels, and more recently on schooners . This sail is not easy to
manoeuvre in
strong wind and during tacking. It is mostly for distant sea sailing.
-
The lateen
sail is
Mediterranean , it is the type of sail to be seen on galleys, xebecks,
feluccas.
The jib mostly used as bowsprit sail or stay sail s another form of
lateen sail.
-
The
fore-and-aft sail and
the sail of a lugger are two types of sails used on
fishing boats and coastal shipping. They can easily be
lowered or pulled up , thy allow easy tacking in coastal shipping.
The
propeller appears
at the end of the 19th century, with the development of the steam
industry and later of the petrol engine. After the
invention of the diesel
engine in 1910, coal and petrol were abandoned in the 1920’s . They
were
dangerous and not well –adapted to fishing. They were replaced by
gas-oil
still used nowadays for engines from three hundred to twelve hundred
horse
power.
Towers
are no longer moved by propellers but by two engine of the “voit
Schneider”
type made of rotors and blades much easier to manoeuvre.
Embarked technology.
You are now
standing at the captain’s place on the bridge for a little
journey through the first half of the 20th century.
Hold the
helm to go on the port side and starboard while you keep
an eye on the compass. The shatburn allows you to
communicate with
the engineer who is in the engine room; For astronomic sailing the
sextants
and the octants which are behind you in the window will be precious
instruments to keep the reckoning .
If you have
any problem with the longitude, observe the marine
chronometer will help you
to return safely to the harbour.
As for the
depth under the boat, you only need to trust the sounding lead
You will now
move to your right on the bridge and you are going to sail
into the 21st century with embarked technology.
The
on- board computer
will give you most of the necessary information : the marine map,
the
cape to hold, your speed, your fishing book, or the tide times for each
port.
The sounder will tell you how deep the sea is beneath the hull
as well as
the presence of fish shoals