Foaming a hull

When you compare the flotation of the cc foam with other brands, you would see that the CC is over-flotationed, like a Ranger or Whale boat. Cut a big chunk of the hull away with a chain saw and look, it still floats, wow, makes for great ads but its still a dead boat.

Other brands have two strips of foam under the gunnels, some in the bow, and a few strips under the floor about the size of two 2x4x8's each side. This passes USCG positive flotation requirements.

Our clubs '68 nautique was in an opposing, glancing collision with another boat (wood) with was a splinterd pile of kindling flotsom. The nautique didn't even spider crack, just a 4' scratch in the gell.

I believe cc hulls have 50-100 % thicker glass layups than most similar boats. I maintain they do not need the foam for rigidity or anything else like that. in order to provide viable regidity, the foam would need to be bonded to the bottom of the floor to make a laminate structure, which it is certainly not. If you need mushy foam to make a boat rigid, caveat emptor.

Whether the foam obsorbs water or not, it still traps water and blocks vetilation. If it's a boat, water finds its way to every spot whether it's under the deck or in the floor. It will be interesting to see how these new houses with the spray foam hold up after some years. Good source for foam though.

Waterdog wrote: Or flip the hull, fill the bow about a foot thick and fill the gunnels under the "lip".?

This is a alternate to foam in the bilge that I've mentioned several times. Flipping is not needed. It's sprayed on. Spraying and injecting foam is actually more common to pouring. Pouring is more of a specialty product that many here use. Lot's of waste with over pouring.

storm34 wrote: Why not seal all the foam and the place it under the floor? Something similar to putting plastic over the foam in your seats then putting the skins on. You could place the plastic (other other similar material) in the floor, pour in the foam and then seal the top. Put your wood floor panels down over top, making them removable so you can check/remove the foam if need be.

dochockey wrote: The foam is just there for flotation? dosent it also act like glue and reinforcement ? all we need to do is come up with a foam that dosent hold water

Use the search set for member UK1979. Roger has done all the water absorbsion tests as well as the plastic wrap idea. The new closed cell foams do not absorb water!!!!

How much structural strength foam adds to a hull is up it the air. Early hulls were thick. Later not so and CC may have counted on the added rigidity. Some feel it also adds to sound control.

Chris,
I'm not in favor of refoaming but if it is done have always pushed injection over pouring. Injected in a cavity, the foam self skins at the outside surface. This makes it very resistant to water. Roger did some testing with the skining factor too.

The foam is just there for flotation? dosent it also act like glue and reinforcement ?

all we need to do is come up with a foam that dosent hold water

I would have to agree, nothing good can come from foam in the bottom of a boat. However, if floatation is a must, than spray it all you want under the gunnels, under the bow, whatever, just not in the bottom of a boat.

Just my 2 cents

Jeff

There's nothing good that can come from foaming!!!!
Extra weight, trapped water, ants, rot, mildew...all bad things.

I have thought of this before. I see the Icynene truck on the freeway all the time. Another option, I think, would be foam in place packaging like we use at our office for packing big computer systems. Sealed Air makes a pretty wide variety of products and probably an adequate one for those who elect to refoam.

C-Bass wrote: But how does this figure into the debate of foam vs. no foam. Pete, would you re-foam even if it were free?

No!! I just wanted to throw the option out there to those that do refoam.

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