Anatomy of a Top Hat

[Killick69]

Does anyone know the anatomy of a mark 3. I am referring to the area under the floor of the cockpit locker (port side).It would seem to be triangular (horizontal floor of cockpit locker, vertical side towards cockpit and diagonal keel). On my boat this seems to be a sealed off cavity. If this is correct, what if water gets in? Is it possibly a flotation cavity?

I have a water rotted ply board that runs vertically from the hull (so it seems to me) to the underside of the cockpit floor. This board is visible when looking aft into the bilge area and is also visible when one looks into the cockpit locker. The ply board seems to sit alongside a GRP 'wall'. This is the vertical wall of the triangular cavity referred to above. I can understand why the cockpit locker floor is sealed (if not water would enter the triangular void and have nowhere to go).

I need to replace all or most of the board. Initially I thought I would have to cut out a piece in the locker. But unfortuntlely most of the ply board is wet and rotten and I don't look forward to working in the area furthest aft (not much room to work). I am also perplexed as to how the board rotted, as I can't see where the water is coming from (maybe the pushpit?).

Ideas and suggestions welcomed
Cheers, John

[Miker]

Photos John, it's hard to imagine really what you're talking about.

All Top Hats are different inside. It's a product of them mostly being fitted out by their original owners to their own style and requirements.

The 5 boats on Lake Macquarie last weekend were testament to that, every other Top Hat I've ever seen is completely different inside.

Also, if it's just a piece of ply, it most likely isn't structural, or necessary, but a good set of photos might help us determine the severity of the problem.

Michael