I have been thinking about how to use 1/4 inch cedar strips left over from a boat project for kiteboard cores...
Normally people claim success for cedar or poplar cores 11-15mm thick with 4-6oz glass laminate top and bottom.
More laminate is needed for a thinner core, but how much more?
The typical ~12mm wood strip board is ok with 6oz glass skins.
The typical ~12mm foam core board seems to have 18 to 20+ oz glass skins.
So as a rule of thumb (and oversimplification), it seems for glass skins, you need 1/3 the laminate for wood strip core compared to foam core.
Also know a few years back folks made boards with ~12-15mm foam core and 12oz carbon skins.
I don't know too much about more sophisticated layups for thin cores, but know from the website that the company, "Brokite" makes 1/4 inch thick foam core boards supposed to be durable and reasonably flexy with 6oz S glass skins over essentially 22 oz carbon -this might be sort of equivalent to approximately 45-50 oz glass skins in terms of overall strength, but it is more complicated because the brokite boards are heavily stringered....
Does all this suggest that a 15-18 oz skin for a 1/4inch cedar strip core might be right (following the pattern of ~1/3 the laminate required for wood compared to foam)?
Or am I off base and extrapolating way too much?
I have Larsson & Eliasson to fall back on for basic composite sandwich design equations, but how well that translates to kiteboards in the first place I am not sure, so I thought I would ask here, if anyone has the experience....
I know gbleck just made a 1/4" poplar core board with 10oz glass skins, as posted here, but I think I would want something stiffer.
Was kinda thinking of making my board like this:
(top)
6oz foot patches
9oz S glass
6oz Eglass
1/4 cedar core
6oz E glass
9oz S glass
(bottom)
FWIW the other cloth I have around besides 9 oz S and 6 oz E is 6.6 oz carbon uni....
Anyway, suggestions appreciated, especially from experienced wood strip builders (zfennell,. gbleck, etc.)!!!
And thanks to you guys and others for the info you have shared before!