Because you're never going to seal it 100%. Over the months and years, water will get in.
*There are rare cases of exceptional hull builders where the back does stay sealed for years. As a novice, you have zero chance of achieving the same. Water intrusion is a fact, plan around it.
Pouring foam does provide some support. It's the sheet foam that does not. The hull should be able to support itself, ideally.
The 2-part urethane pourable foam has a tendency to soak up water and make the ski very heavy over time. The sheet foam doesn't do that.
For a good mix, just fill...
This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
By continuing to use this site, you are consenting to our use of cookies.