Floor hatch cover

[Flukinicehole]

I just got a 89 Mark Twain walk around and the gas tank floor hatch is soft.The hatch is fiberglass with wood then one layer of fiberglass mat.The wood rotted and I dont know what to use to replace it.The hatch measures 33by43.If I use plywood I think there will be a lot of flex.Is there any kind of waffle board available?Or will 3/4ply be O.K? Thanks for any help.I also want to keep it as light as possible as the boat already weighs 4200.

[dmarkvid2]

If you build the hatch from plywood, 3/4" is good. I would try to install a 2x4 Or whatever the size you're using for the frame down the center of the hatch cover for extra support. Once you glass it, it should be really strong, and shouldn't have any movement. If you plan "just" to use a piece of ply, and no frame, you will have flex.

[Flukinicehole]

Thanks this is what I was thinking.I was hopeing for a lighter suggestion but will probably go this route.

[tashasdaddy]

they make a composite hatches, whether you can find the size you want is the question. google boat hatch.

[Flukinicehole]

I talked to a guy today that makes body panels for race cars.He gave me a great idea.I will use wood so the seats have a good anchor.To make it ridgid Im going to cut a piece of 2in.pvc in half length wise.Put a release agent in and make a fiberglass mold.I will then glass the u shaped supports to bottom of hatch.He says this will make it plenty ridgid.Hope it works.

[epresutti]

Flukin......I build this one out of 3/8" with 1 x 2 frame, layer of glass on bottom and layer of glass on top. It is very strong, 72" long by 24" wide. Peace.Ed.