[quote="rodotYes Bob. I'ld like to make it light so it will be easier for an old fart like me to lift it on the roof racks.
Roger[/quote]
I can relate to that

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Lightness is one of the many good things about my Laker but I would like it even lighter still and when/if I build again I have a recipe worked out.
Glass will be 84g (about 2 1/2 oz) as used on the Laker. The stuff I bought is a bit pricey but is very good - wets out easily and conforms well. Lighter glass also cuts down on resin and considering it goes on both sides a lighter grade can make a noticeable difference.
Timber will be Paulownia strips glued into panels about 5mm thick. This stuff is less dense than WRC or Gaboon and reasonably priced. Last time I checked I could get quality Paulownia delivered to SA from northern NSW at about the same price as quality Gaboon ply (without transport cost). Obviously the Lauan will be cheaper but unless it has as many voids as mine (:roll: ) it will be noticeably heavier.
I believe this combination will be strong enough for most people. The thickness would give enough stiffness which is what we really want unless poking around in a lot of rocks in which case a second layer of glass on the bottom may be in order. Personally I would go with the lightest combination and add another layer if I struck wear problems.
In the end it depends on your intended use /budget etc but it is another option to consider.