sorry mate i thought you were saying poly as in polyester would deteriorate doh!!.larry i think balsa would be a good choice 1/8 thick will make it sturdy then just use 120 g cloth and either polyester resin or epoxy and she will be nice and strong.glad you liked my sons boat i built her for his xmas present she goes pretty well running a 540 car motor and a mechanical speed control and powered by a 7.2 volt pack.still need longer duration so im getting him a higher mah pack or two.if you fancy the plans to that higgins boat i have them in pdf format.check out my build thread here for building pics.good luck with your build.
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