ORIGINAL: Ron Olson
You got lucky! A lot of times the 2-part or spray-in foams will blow the deck off the hull. If you use it in a nitro or gas powered boat it will also soak up fuel and oil over time.
Depending on the size of the boat, you can use pool noodles or foam pipe insulation.
It wasn't luck Ron, I tested it on a plastic bottle. As I stated earlier, it expands like the bubbles on top of your cola, very soft, conforms to the cavity, it DOES NOT push. Once expansion is complete, it then hardens.
Is your statement on the 2 part foam based on experience, or common knowledge? I, on the other hand, know from experience with it. Unless there is another brand of 2 part that does react the way you describe, because this brand didn't. That is why I posted an image and a link to the brand I used.
EDIT:
As you can see, I didn't have an option for noodles, or pipe insulation. [
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