[MHml] foam core vs cedar strip

[John Shuttleworth]

I have just done the calculation on the Shuttle 40 "Zazen"

If you make everything in foam sandwich except the hull and decks over the
hulls the added weight is 500 Kgs even with the glass reduction.

Just doing the hulls below the sheer line in Cedar strip planking adds 340 Kgs.

regards

John

On Wednesday 14 February 2007 16:01, Jeff Lebesch wrote:
> That a foam core assembly is lighter is probably widely known. ?I
> have heard cedar strip is about 28 lb/cu-ft, typical foam core about
> 5 lb/cu-ft, but in a cedar core composite the glass weight can be
> reduced, so the finished weight difference between the two materials
> is not as great as might be expected. ?Any data on this?

I recall John Shuttleworth told me that when one client asked him to look into
the weight of cedar strip for one of his smaller designs the final difference
was around 5%.

Of course I do not know if it was ever built so it might just be theory. I do
know John prefers foam core and knows fairly accurately what _that_ will end
up weighing if built correctly.

Gary