Help with plywood grades

[stephen low]

Bit off topic chasps but am rebuilding a powerboat and I need some feedback on plywood species.

I have been getting prices on the plywood I need to do the job as I am reflooring and replacing the transom. So am looking at 12mm for the floor and 15-16mm for the transom.

However prices are all over the shop which I was hoping might provide me with some sort of quality guide - seems not! For example, in 12mm thick structural grade I can get ply sheets from about $50 up to $100 or if I go the Aust Standards stuff even more expensive again.

I am less worried by cost and most focussed on the functional need from the ply. Clearly the transom timber needs to be dense and tough to hold nearly 200kgs of motor but the flooring I can get away with something less.

Am trying to get timber species names for the plys and know hoop pine is one good variant and have also been quoted for Birch, Phillipine Mahogany, Maple and F14 rated plywoods.

These I believe are all structural grades and as waterproof glues are used in these plys and they will be sheathed both sides in fibreglass, there is no immersion issue again just strength.

So what should I be looking for in terms of ply timber species for strength and density, can anyone help???

Looking to some good feedback.

Cheers

Steve