Foam/glass

[Doogie S]

I had a buddy who used this method to build a whale tail for his 260Z. It looked OK, but he must have had some small pin holes in the fiberglass and used the wrong foam, as it absorbed a lot of water weighed a ton. The hatch supports wouldn't hold it open.

As for roofers Styrofoam, there are a couple of different types. The blue Styrofoam is Type 2, which works pretty good. If you have the yellow/beige type, it is most like Polyisosynurate. A really high insulating foam, but extremely caustic if it ever catches fire.

There is also a blue Styrofoam that is Type 4, which is rated for contact with the ground, which should be better against moisture absorption.


Doug