Repairing fuel tank deck hatch coring

[blindmullet]

Tanks looked like crap from the plywood glue leaking on them but they cleaned up well. No salt water corrosion on tank top. Obviously I can't see the sides well but paint was still adhered to the tank.

Deck hatch project finished. Coosa board, West System epoxy, glass fabric covered and vacuum bagged. Holes re-drilled and epoxy coated.

Pumped water out from underneath tanks - no fuel. Hooked up smoke machine - no leaks. Pressure tested tanks and sprayed hoses - no leaks.

Changed access ports out. Caulked everything with 3M 4000 including the deck.

It's overkill but done right done once!

Photo after vacuum bagging before glassing in.
View attachment 16738

Run some thick filets on that support. Those sharp angles will be hard to glass.

 

[Fishtales]

I agree with the 1/2" marine ply. Will prob outlast the boat at this point.

 

[Hookup1]

Run some thick filets on that support. Those sharp angles will be hard to glass.

I vacuum bagged the assembly. The plastic shrink wraps around all the edges, draws all the air out, presses glass in place, fills voids with epoxy and brings the excess to the surface. Not that difficult to do. www.FiberGlast.com

I forgot to take a picture of the finished deck - already re-installed.

 

[DennisG01]

I vacuum bagged the assembly. The plastic shrink wraps around all the edges, draws all the air out, presses glass in place, fills voids with epoxy and brings the excess to the surface. Not that difficult to do. FiberGlass.com

I forgot to take a picture of the finished deck - already re-installed.

But, where is the bottom layer of glass? In the picture, it doesn't look like there is a layer of glass on the foam.

 

[Hookup1]

But, where is the bottom layer of glass? In the picture, it doesn't look like there is a layer of glass on the foam.

Vacuum bagged twice. Photo is with Coosa board installed. I glassed the whole thing over as the original and vacuum bagged it again. I forgot to take a picture before re-installing. Sorry - I'm not taking it up!

 

[DennisG01]

Vacuum bagged twice. Photo is with Coosa board installed. I glassed the whole thing over as the original and vacuum bagged it again. I forgot to take a picture before re-installing. Sorry - I'm not taking it up!

That's OK, I don't need to see a picture of the glass - I'm pretty familiar with what that would look like! It just seemed like you omitted that step.

I've never vacuum bagged anything... so that was able to pull the glass down tight over those 90* edges? No bubbles?

 

[Hookup1]

That's OK, I don't need to see a picture of the glass - I'm pretty familiar with what that would look like! It just seemed like you omitted that step.

I've never vacuum bagged anything... so that was able to pull the glass down tight over those 90* edges? No bubbles?

Here is my hatch for the anchor locker. I'm installing a new windlass. Lewmar Pro Fish replacing my Horizon 700. All the holes line up wrong so I repair all the holes and drilled new ones. Grady cored the hatch with two pieces of plywood joined in the middle. I installed a piece of Coosa board and put a layer of glass on both the top and bottom. I'm waiting for gel coat to come in to finish it up.

The edges of the Coosa board were beveled. I used heavy clear plastic from Home Depot for the bagging. Had I used a stretch wrap on the Coosa board side I would have tighter edges but its good enough.

 

[blindmullet]

Vacuum bagged twice. Photo is with Coosa board installed. I glassed the whole thing over as the original and vacuum bagged it again. I forgot to take a picture before re-installing. Sorry - I'm not taking it up!

The radius is also for strength. You won't see many sharp 90s on a boat. Obviously, you over built and should be fine.