@rob i have to admit that I was wrong about some materials used in the 380 build
The deck is? balsa cored as mentioned before.
The hull is solid glass below the waterline and foam core above, and not balsa cored as I said previously. I just had a look behind the head's wall and it looks like there is foam in the main areas and some balsa trim on the edges. Please find attached a photo of that section.
I never had to drill a hole in the hull above the water line so I relied on second hand knowledge and that was wrong. Sorry for any confusion caused
The Bimini top itself seems to be foam cored as well, at least I just poked out some foam when doing a small repair.
