Hatch recore
 

So the fuel tank hatch on my 73 20SF has become rather soft in front of the console. Has any one recored one these? If so what is it, 3/4 plywood? Any help would be great, thanks.

It doesn't really matter what it is, but more what you replace it with. What you are proposing is fairly common, and everything from plywood to foam core has been used. The good thing about the foams is that they wont rot again and are light weight. I bet you will be shocked how heavy that hatch is when you pull it out. Especially since it is most likely waterlogged. If you type this into google, I bet you'll find a ton of step by steps with pics to help you along. Easy job.

I installed a 6" inspection plate in the rear of my fuel tank hatch over the sending unit and pick up. when I removed the cutout, it was literally dripping water. I weighed it immediately upon removing it. I let it dry for a couple of months then weighed it again. That 6" cutout lost exactly 1 pound! by my loose calculations, the entire wet hatch had approximately 45 pounds of water weight!

I just built one from scratch and documented it. I used nidacore. For another fuel hatch I used divinycel H80 foam. I think you can get nidacore in 2 x4 foot pieces from LBI or other suppliers. It won't rot or wick water until it weighs 80 lbs. Like my old fuel hatch cover before I replaced it.

http://www.classicseacraft.com/commu...ad.php?t=28820

You don't need to vacuum bag but peel ply is nice.

Also a repair on the hatch for the 25 with foam and no vacuum.

http://www.classicseacraft.com/commu...1&postcount=63

Good luck!