Time is a crucial factor not only for factory built
boats. Building a boat in your spare time, besides small ones, is a time
consuming pastime. Take as example the DUO 800. The boat can be build in 800
hours. Say, after work you can spend 2 hours per evening + 10 hours on every
Saturday. The total will be 30 hours per week. The construction time will be
then 27 weeks. This is without collecting material etc. but overall this is not
bad. Now consider to build a similar boat in a sandwich
construction.
Ultima Ratio rebuilt in
Spain
Here is a
photograph from the �Ultima Ratio� a Piver Lodestar. Between 1969/70 Mrs.
Ingeborg von Heister crossed in this tri the Atlantic in both directions. The
second owner sailed the boat in the Mediterranean sea. The boat was a bit
abused, standing the last 4 years in sand. So the keel was bend and as a
consequence the hull sides cracked on two places. After the boat was palled
correctly the hull straightened it self almost out. Otherwise the boat is sound.
For better protection the boat will be now covered with glass fiber and epoxy.
This shows that even plywood boats lasts long if properly built. There are of
course many more examples but this is outside the scope of this
article.
Almost all production multi hulls are build from glass fiber
and polyester. Polyester as an matrix is any way not a good choice for a multi
hull because of the high cyclic loads on this boats ( bridge deck hull
connection etc ), because polyester becomes bridle over the years. One of the
reasons is, it never stops curing. One-off and racing multihulls are often
build in one or the other foam/sandwich system depending on budget in a
combination of carbon, aramide, E and S-glass fiber and epoxy. To obtain optimum
strength and lightness with such a system, vacuum curing or a infusion technique
has to be used. Techniques you have to learn first. Boats build with any of
these systems require molds or complicated template constructions. Nothing of
this is necessary to build a plywood/glass/epoxy boat.
GENERAL
Wood is the
oldest boat building material. Some wooden ships exists which are more as
400 years old. In the Netherlands some of the Botter and Aaken ( old
fisher mans boats ) are more as 100 years old and still sailing. There are more
examples the world over. So, after all wood can be not so a bad boat
building material. Today we can enhance the already good properties of wood by
using epoxy to protect and strengthen the wood. By impregnating the wood on the
inside with epoxy and covering the outside of the boat with fiber glass the
result will be a strong, low maintenance and long lasting boat. Wood has no
fatigue symptoms in contrast to all other boat building materials. This is very
important for multi hulls with there high cyclic loads. When you compare the
costs for materials in any other construction system, wood is the most cost
efficient material. Most interested persons will have some experience working
with wood. So, when you start, you know what you are doing. It is easy to check
a say, deckbeam to deck connection by eye. To build a foam, glass boat,
where you have to use a vacuum technique, will be a different story. How to you
expect to check a deck to hull connection for instance ? Building a boat out
of plywood/glass fiber and epoxy is a good choice for amateur boat builders or
for one off multi hulls. Is it the best boat building system ? for amateur multi
hull boats it is a clear yes.
