how much fiberglass should i use

so im wondering...

...im building a yacht which is 32 foot long........just under 10 meters..

..which is 3.2 meters wide...

..and have calculated.....the hull surface area to be 38....square meters...

..

...so how much fiber glass should i use if i want for just the hull.....if it is 100 per cent fiberglass....no core or anything...


I though about 4 cm thick ness.....would be good...

but that would set me back about 8000 dollars...


....and the plans told me to buy 450 kilograms of fiberglass...

....but the plans are for a 12 meter boat........so then i should buy like 370 kilograms of fuber glass....for a 10 meter boat....i thought


which would only cost 1800 $$$$$



...but that calculates to like 6 layers.....of 450 gms chopped stand mat.....

which will only be 6 mm ....thick.....then im thinking ......like a small power boat is 6mm thick......

so im complety confused......


so ive brought 1 roll of 450 gsm chopped stand mat..........which probly has 80 meters .....of fiberglass.......and weigh s 36 kilogram....


so can anyone help me on the thickness of my boat.......

 

As a fellow amateur, I recommend you get a copy of Dave Gerr's "Boat Strength". Since you have a particular boat in mind and know how you wish to use it, you can work your way through the book cookbook fashion and figure scantlings for everything from bulkheads to bellropes.

 

How is it that you calculated for the loads on this boat? How did you determine where the bulkheads and other athwartship stiffeners needed to be? Do I have to even ask about longitudinal stiffeners? In other words, you're really out of your realm if asking these types of questions, particularly on a craft that can take you well past the point of being able to swim back to safety.

I'm not intending to insult you, but how much confidence would you have, being in an airplane where the designer went on line and asked "how long do I need to make the wings . . ."?

 

Following on from PhilSweet, have a follow up on "Fiberglass Boat Building for Amateurs" By Ken Hankinson it answers a lot of questions and how tos