: I am going to buy the PVC to cover my sea tour (winter project) and
: to build an inflatable kayak (sonnet probably). I could choose
: between 16 Oz. PVC (made of _polyester_ core coated both sides
: with vinyl) or 13 Oz. PVC made of _fiberglass_ coated both sides
: with vinyl.
: The 13Oz seams tough enought but less flexible. The 16 Oz looks
: more "gummy".
: Which one is the right one?

check out these guys:

http://www.mytarp.com/vinyl-fabrics.aspx

very good prices, and they sent me free samples quickly. all their quality seems pretty good to me. havent built with it yet, tho. probably gonna do a sonnet next spring (2 seatours gotta get done first).

kOz