Not all wood stringers are the same?

[saaristo]

Just recently I have found an article in the web (apparently written by some boat surveyor, can't find it anymore) who in a way implied that wood in a stringer can be used for two different reasons - short take of it would be something like if your glassed wood stringers are thin looking (some half an inch or so) then the wood itself serves the function of stringer. If however, your glassed stringers are fat looking (around two inches) bars then it means the wood inside serves there only the function for initial forming of the stringer and the rigidity function is on glassfibre applied on top of the wood. Another words, the wood is still quite thin inside, just that it's the huge amount of glassfibre that makes it fat. Therefore on the latter case it doesn't really matter what kind of rotting process takes place in the wood itself.
Is it really that simplistic...I kind of doubt.

 

[rallyart]

First off, not all wood is the same that is used in stringers. Some wood will not rot if it sits on the bottom of the water for 100 years. It depends on how it is treated and assembled. Next, if they are using wood it is for structural purposes. They could use a block of foam rather than wood if the fibreglass was the sole structural member. Thin or thick does not matter. The choice of fewer thicker stringers or more thinner stringers is just a manufacturing and design decision. Don't use it to determine if there is wood in the centre or if it is structurally important.

 

[tpenfield]

Most of the ?fat? (wide) stringers are foam filled and have no wood (or an insignificant amount of wood). The strength in those types of stringer does come from the fiberglass being 4-5 times thicker than a glassed over wood stringer. However the shape and width of the foam core is more the determining factor than thickness of the fiberglass.