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Lawrence James
 
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Default Composite stringer grids

I suggest you take a look at some standard floor joist simple span tables
and see just what it takes to span 10 feet. Conventional wood is not very
resistant to flexing. A lot of other things are stronger.

An all composite, no wood boat is a lot better than one with wood in it.

Just because a lot of boats have been made with wood does not make it good.
It just means it is cheap and easy.

"Harry Krause" wrote in message
news:c3dhc2g=.82627d12784c03afb2097e72f24ffd36@106 9256316.cotse.net...
K Smith wrote:


Wood is not a very strong material at all.


Bull****. Wood is a very strong material when used appropriately.



Tougher hardwoods have very
moderate strength in compression, but other than that wood is a very
weak material with low resistance to flexing & even worse performance in
tension. i.e. bend a piece of wood to simulate a load in the middle; one
side is in compression & the other is in tension.



Yeah? Tell you what. Envision a wood stringer, say 2"x10"x16'. Tip it on
its edge. Now, try to bend it in the up or down plane with any load
similar to what you might find in a working hull. Now, build that 2x10
into an eggcrate sort of structure, with cross members of the same or
similar material. Now subject that structure to lateral loads. Doesn't
bend that way either.

This is real world construction here, Karen, not some crap you lifted
off a web site.



The wood will bend
easily & a great deal, it will usually then break as the tension side
fails. So I'd like to submit the problem with wood is that it's wood.



The problem isn't wood in boats. It is the wood between your ears.





Most anything designed in wood is strength for strength much much
heavier than almost any other material, steel, glass, even ferro. This
is because the material is inherently weak & this weakness is aggravated
by the difficulties of attaching it to anything, even itself (mechanical
fastenings, nuts & bolts are about the only real fix)



Really? Gosh. There probably are 100 million wood frame houses in the
united states, some more than 100 years old. I suppose that because of
the weakness of wood and the difficulties of attaching it to anyting,
even itself, are really problematical, eh?



It might be a "normal" process when you glass over wood because resins
will not ever properly bond to wood


You ought to send your resume to Grady-White. I'm sure they'd be
interested in hiring you because in your opinion, the boats they build
are likely to fall apart any moment; their stringers are constructed of
XL plywood covered in fiberglass.

But what could Grady-White know about boat=building, compared to the
Australian bull**** artist, Karen Elizabeth Smith?




I'd like to also disagree with this if I may. Hollow sections are never
as strong as three dimensional webbed or bulkheaded sections. i.e. say
in steel a rolled hollow section (RHS) of a given weight is never as
strong as as a universal column (RSJ) of the same weight.


An important principle to keep in mind when building small boats, eh?


More Karen lifts from engineering webpages, but no understanding of
materials or applications.








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