Rampone Hatch Recore

Shine,

As stated in my first post, I have some work to do on my 1978 Rampone 25.

The first project is to re-core the aft hatch cover. The wood (probably original) is shot. The deck is soft, the hatch weighs a ton and it drains water when on its edge.

The hatch measures 61" wide x 67" long. The two inboard stringers (which support the center of the hatch) are 24" apart. Outboard stringers are 17" from inboard stringers.

My questions are: What thickness marine plywood should I use? 1/2"? 5/8? 3/4?
And what resin to use? Epoxy or Polyester?

My intention is to keep the boat for many years. I will be making it safe first, functional second and then turn it into the multi-purpose vessel I plan on it being.

The plan is to remove the hatch from the vessel, cut out the old 'glass on the bottom of it, remove wood, cut new pieces to complete jigsaw puzzle and resin them in place, cover with fiberglass and reinstall aboard.

Any expert advice you can provide will be much appreciated.

I've followed your postings regarding your 23 footer on Classic SeaCraft and had hoped to rebuild an older 23 until this hull popped up on my radar. The work on that 23 was off the charts. While I will not be able to match that level of expertise, I aim to make this hull my own private dreamboat.

Many thanks,

Buzzcutt

Hi Buzz,

That is a very large hatch, you will nee more than just a core to make it stiff enough. You will need stiffeners (stringers) on the hatch cover. A span of 61" needs to be broken up by stiffeners . How much room do you have on the underside of the hatch? I would be looking at a 1/2" core, and three 3"- 4" stiffeners. Stiffeners could be plywood on edge or PVC glassed in. I would absolutely use epoxy, for the bonding, but also to keep it light. With epoxy you dont need any mat for bonding, so you laminate on the underside and the glassing in of stiffeners can be with plain biax glass (no matt)

Joel

Joel,
Currently there is no stiffeners under the hatch. The hatch rests on a lip that runs around the edge of the hatch and on top of the two center stringers. I had planned on leaving it that way until I do a complete hull up rebuild.
In addition to recording the hatch, I plan on filling in the forward access opening and enlarging the aft to allow access to the fairly large bilge compartment underneath.

The center stringers are 24" apart and run the length of the hatch. The hatch will have a maximum unsupported span of 24". With the stringers supporting the hatch, would it be safe/practical/wise to rebuild it with the 1/2 core and no additional stiffeners?

Thank you,

BuzzCutt

Ok, that make much better sense. If it was stiff enough before then, yeah just replace the original core thickness.

Joel

Joel,

Here are a couple of pictures of the hatch.

looks like it was in contact with the tops of the stringers, so that splits the loads. If you "pin" or fix the hatch to the tops/sides its more stiff than just being supported