Originally Posted by doocruiser
i recently purchased a 34 ft plywood catamaran
that was constructed using stitch and staple/epoxy glue method.the whole exterior has been finished with fibreglass mesh and epoxy resin.the guy that built the boat has not sealed any of the plywood,stringers or any of the internal woodwork.he is adiment that one side of all the wood should be left unsealed so it can breath and if it does get wet so it can dry out. other people i have talked to with experience have said exactly the opposite and reccomend i seal the entire inside with a brushed/rolled layer of epoxy resin. there is a lot of water in the air on boats and leaving wood exposed does seem concerning.
any advice about this would be greatly appreciated.
IMHO, after having managed a lumber
and building materials division of a home center for 20 years, and having built a number of boats utilizing various types of plywood, is,--there are as many answers to this question as there are types and grades of plywood. Marine
ply can be had in Fir, Pine, Luan, Meranti, Sapele, okoume, (sp) and probably more I havent listed.
Having sold thousands of sq. ft of "mahogany" type material, I can tell you to not trust the Indonesia
products, which IMO have substandard cores, with numeruos voids.
The BS 1088 stamp does not always guarantee a good product either.
Brunzeel and Thames were generally the better "mahogany types.
My experience has been that the higher the ambient humidity when sealing, the higher the likelyhood of rot