We bought a johnboat and thought the it was oddly heavy. This weekend we
discovered that the foam under the deck was saturated with water. The
oddest thing I have ever seen. After removal, the boat is easily handled by
two men. It took four before. So now it has no foam for buoyancy. I
obviously want to replace it. The old foam was covered with some sort of
plywood, which has disintegrated, and aluminum sheeting. I would like light
weight substitute to perform the stiffening function of the plywood.
Without it, the sheeting will be destroyed. Any suggestions?

On Mon, 27 Apr 2009 10:24:51 -0400, "Dan Listermann"
wrote:

We bought a johnboat and thought the it was oddly heavy. This weekend we
discovered that the foam under the deck was saturated with water. The
oddest thing I have ever seen. After removal, the boat is easily handled by
two men. It took four before. So now it has no foam for buoyancy. I
obviously want to replace it. The old foam was covered with some sort of
plywood, which has disintegrated, and aluminum sheeting. I would like light
weight substitute to perform the stiffening function of the plywood.
Without it, the sheeting will be destroyed. Any suggestions?


If the foam is non structural then you could use Styrofoam and cover
it with a layer of glass cloth - use epoxy for this as polyester resin
will dissolve the foam.

I built an air conditioner housing using sheet Styrofoam and epoxy
some years ago and it is surprisingly sturdy.

Cheers,

Bruce in Bangkok
(bruceinbangkokatgmaildotcom)

"Bruce in Bangkok" wrote in message
...
On Mon, 27 Apr 2009 10:24:51 -0400, "Dan Listermann"
wrote:

We bought a johnboat and thought the it was oddly heavy. This weekend we
discovered that the foam under the deck was saturated with water. The
oddest thing I have ever seen. After removal, the boat is easily handled
by
two men. It took four before. So now it has no foam for buoyancy. I
obviously want to replace it. The old foam was covered with some sort of
plywood, which has disintegrated, and aluminum sheeting. I would like
light
weight substitute to perform the stiffening function of the plywood.
Without it, the sheeting will be destroyed. Any suggestions?


If the foam is non structural then you could use Styrofoam and cover
it with a layer of glass cloth - use epoxy for this as polyester resin
will dissolve the foam.

I built an air conditioner housing using sheet Styrofoam and epoxy
some years ago and it is surprisingly sturdy.

Interesting idea. Thanks!