Fiberglass strength

I plan to glass 3 layers of #6 cloth to my 13 foot long "foam" boat prototype.
Are there any specifications/formulae on the strength this glass and solid foam this boat will deliver? From tests on the model it seems to have lots of strength to handle a summer of testing while carrying 1 or 2 adults.

 

Are you using epoxy resin ?

 

Yes and it works good on foam.

 

I'd guess it all depends on what rigours you intend to put this boat through, but it sounds like the kind of laminate used where light weight, even ultra light weight, is required. Your project needs to be assessed in its entirety, with consideration to what kind of vessel and what its intended use is, before any meaningful assessment can be made of the adequacy of the lay-up. What suffices on the local duck-pond may be a hazard elsewhere.

 

An equal weight single skin of biax or triax will be stiffer and stronger than the woven glass. The issue would be fitting to
compound surfaces.

 

Triax/biax

Thank you Tom...Do you think one layer of trimax would be sufficient? Would this be equal to 3 layers of #6 cloth - are there any fiberglass strength guidelines/formulae's that you are aware of?

 

Ah - Ron, here you are on the big version of your weight issues.

You are a bit short of details though. I am betting you are planning a solid foam hull.

If you do, you are going to find it very heavy once glassed, compared to a hollow hull.

However, as soon as you go hollow, the thickness of the hull will have a considerable affect on the fibre thickness required.