In the present absence of time to write a full article here, I will at least temporarily post some useful links where some information can be obtained.
Here's a good, overall article to get one started:
Automotive applications may provide some tips too: www.rqriley.com/frp-foam.htm
And here's a potential supplier to get an idea of prices: www.boatbuildercentral.com/
And I would be amiss to not include what Sir Ian has to say on the subject:
"New articles, comments and references will be added periodically as new questions are answered and other info comes in relative to this subject, so you're invited to revisit and participate." —webmaster
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