No core floor

[DMAL]

Ayuh,.... You need to build in some sorta structure for strength,...

Properly placed cardboard or plastic tubes, cut in half, 'n glassed over creates stiffness,....
Maybe strips of stiff foam, 'n well glassed over,...

Kinda like workin' tin,.... flat sheets are flimsy,... a few bends in it, 'n it'll support thousands of pounds,....

I have worked with a lot of aluminum coil stock...I understand your point. I have some aluminum tubing. Is there any reason why Aluminum would be a bad idea?

 

[DMAL]

Ayuh,.... You need to build in some sorta structure for strength,...

Properly placed cardboard or plastic tubes, cut in half, 'n glassed over creates stiffness,....
Maybe strips of stiff foam, 'n well glassed over,...

Kinda like workin' tin,.... flat sheets are flimsy,... a few bends in it, 'n it'll support thousands of pounds,....

Thanks for your suggestion, it worked great. I only had a half of an inch between the floor and the gas tank so I just folded some unidirectional fiberglass to create the structure and covered it with my tabbing material.

My floor turned out to be almost strong enough on its own, but it did need some structure above the gas tank. I used 7 layers of unidirectional glass on the floor in total. The bottom and top layers ran the length of the boat front to back and 5 layers went across the width of the boat sandwiched in between. It ended up about 7/16 thick and a little heavier than I would have liked . I think I would have been fine if I would have stopped at 6 layers. I am just going to have to be a little more weight conscience in the rest of the boat. I was able to pick up the floor by myself so I am guessing it to be a little under 200 pounds.