With wood, get dry wood and coat it with resin on all sides. let that dry, lightly sand it and then apply the Fiberglas layer. that will keep the wood from soaking up moisture and expanding.
If you want some strong plastic composite wood that bends nicely I have a few pieces that were free at work
PM me and I might be able to get some to you. I made the round part of my nose cone from it.
it bends, is strong, will not rot, will not break, will not decay. its great stuff!