18' Skiff Laying New Deck Questions.

[stranchy]

I have a 1976 18' Local built Skiff (San Diego) Plywood and fiberglass. 1 1/2 years ago I pulled the old deck and found rotten stringers. I am finally done replacing all the stringers and now it is time to get prepared for the deck.

I would like to put down Plywood and then laminate it in with Fiberglass and Epoxy Resin. It will be a paint finish at the end.

My questions:
What thickness of Plywood, I thought 3/4"?
What Grade?
Should I coat the underside of the plywood with resin only or glass also?

Do I leave a gap from the edge of the deck to the side walls and fair that in later? If so how wide?

Can I butt the plywood edged to edge without a gap on all seams?

I am planning to make some thickend Epoxy resin as a bed on the stringers before laying the deck and then screwing it down (stainless steel) then counter sinking the fasteners and glassing over the whole deck.

Thank you for the help. A weekend project to 2 years, sound like a boat.

[stranchy]

Anyone have an idea of what thikness plywood and grade to use. Any help would be appreciated.
Answers to the other ? would also help greatly.

Thank you,

[mojounwin]

ply thickness will depend on how far apart the stringers are.

I would think 3/4" is miles to thick. I have decks using 9mm ply with 300gm cloth on the external side. This spans 500mm and is plenty stiff to walk and jump around on.

You want to make sure the play has A bond glue (waterproof) Marine ply generally is better quality and has more plys so will be stiffer. Construction ply is a cheaper alternative.

I have just coated the internal sides of ply with epoxy, no glass.

I wouldn't leave any gaps between edges.

Cheers
Mojo