building a casting deck

Good morning everyone.

I'm in the process of putting a new floor in my 18 foot '76 crestliner. I have decided to do a little modification near the stern and build a casting deck behind the drivers seat. The deck will span the width of the boat (i'm thinking the size will be about 36 x 42). Mainly it is going to be used to cover up the fuel tanks, batteries, and provide some lockable storage for my tackle boxes.

I have no problem cutting the plywood and carpeting it for the deck, but i'm trying to figure out the best way to support the deck. I could use regular 2x4 and build a mini stud wall that will support everything just fine, but I am trying to avoid using wood mainly because of the weight. I was thinking that maybe steel framing might be the ticket. Its lighter and I can just screw and / or bolt the pieces together.

Has anyone tried this, or has anyone worked with steel framing enough to suggest going for it or just using wood?

Any thoughts would be appreciated

thanks

Re: building a casting deck

I've done something similar, used 1/2" plywood and added stiffeners on the underside. The stiffeners were made from a 2x2 ripped lenghwise into 2 triangle shape pieces, then one edge is sanded round so fiberglass cloth will curve around it. Once the stiffeners are fastened to the underside (PL Premium adhesive w/ stainless screws) I glassed them with 1708, carrying the glass a couple inches onto the plywood. Then a layer of 7 or 8 oz. glass cloth on both top and bottom, nice and strong, not too heavy, and waterproof.

Re: building a casting deck

Steel would be a pretty horrible idea for rust reasons of course. 1/2 plywood is pretty strong and not too heavy really. Any steel that would be light enough would not really be something to walk around on. Typical stud walls using them are not load bearing.

Re: building a casting deck

I don't know if i'll be putting glass on the deck or not, but i'll be sealing everything with epoxy. I was wondering about the load bearing capability of the steel. I don't really need the incredibe strength of 2x4 or the weight if I can avoid it. I'll be using 5/8 ply for the deck itself. I may just use steel angle iron. If it comes down to it, I'll use lumber

Re: building a casting deck

My boat has a bench seat across the rear just in front of the engine, they used plywood across the boat, then either side of the engine, 4.3L V6 Merc, they used a composite material from the plywood to the stern, there are metal brackets, Aluminum or Stainless, not sure, that attach all pieces to the boat and each other and then a sunpad on top, it is a sheet of plywood covered in padded vinyl. In your case you could do something similar, the sunpad is hinged across the stern with two gas cylinders to help hold it up when you raise it to get to the engine or the storage area.

Re: building a casting deck

I've seen decks folks build using aluminum angle or square tubing.