if your in a bind, you can get two 1" thick sheets and stick them together, using methylene chloride of coarse. it would stick two sheets seamlessly together, person int. airport in toronto has a floating box type display on terminal 3, right past the gate., its 20' tall and 5' thick, it uses 8 sheets of 1'thick sheets of acrilic. since 2" thick is almost imposable to find and more then twice the price of 1" this might be the better rout. JMO...
also with a bit of top bracing i have seen a 6'tall acrylic tank made from onely 1"thick stuff, and there wasnt a bow or anything.
