It depends on the type of wood and the layup schedule of the glass. It
really needs to be vary carefully analyzed and balanced.

On my 45' hull the designer called for 1.125" thick by 1.75" wide white
cedar with 4 layers of unidirectional diagonally laid below the waterline
and 2 layers above with 2 layers on the inside plus some Kevlar in the
forward slamming areas.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Max Hazelhurst" wrote in message
...
Hello all,

Can anyone assist me with the calculation for strip planking hull
thickness...? We are embarking on a build of a 40ft ketch.

I know there is Dave Gerr's formulae for determining this but have not got
his book (not available in SA). I intend exoxy glass in/out.

Also, what influence will a different wood species make on the thickness
required? ie: mahogany vss cedar vss ... vss ...

Thanks for the info - cheers,
Max