Bad Install of Tubbie Sponsons

click on the thumbnail for a larger picture

I removed this sponson using a flat blade to first chip the bondo off from either end, and then to force it between the sponson and the hull to break the clear "silicone" seal. Note how the blade cut into the foam as the edge of the sponson had pulled away from the hull.
The hull had not been sanded and silicone was not only used to seal the edges (which didn't work) but silicone was used to glue the foam onto the hull. Foam isn't the way to hold these on. Some of the screws were not contacting the hull either.
Note the easily cracked off Bondo and the white bathtub chaulk used on top.

There was surprisingly little water absorbed into the foam. I'm sure most of it leaked out the bottom, but I doubt all of it would have. Probably less than as much water you could get squeezing out a washcloth soaked in water came out with the sponson.

A view of the sponson itself. Notice the deformities as water pressure pulled it away from the hull, and Bondo was later used to attempt to reseal it to the hull. The bondo easily cracked off with my fingers.
On the other side we can see the sponson pulled away from the hull and Bondo used to attempt to reseal it. Without proper sanding nothing is going to stick for long.
Note the washer added to the screw that pulled through the sponson due to overtightening.
Another view of the deformed sponson.

A two part Marine Epoxy, 3M 5200 or similar products are the only ones that should be used to bond the sponson to the hull. Silicone of any type should not be used.

Closer view.

SMC panel adhesive, Marine Tex or similar structural compound should be used to fill large gaps and fair the sponson to the hull. It's got to be sanded first though, no shortcuts allowed.

Another view of the deformity caused by water pressure and improper materials used to seal the sponson to the hull.