How to make a balloon column (By the way, there was a site that talked about the Italian convention, with some insight of the behind the scenes construction of the temple, and they described slightly how Chris constructed the columns (For some reason the site doesn't come up any more). He used 4 inch PVC drainpipe (attached securely to bases I assume, they didn't specifically say), covered them in two-sided carpet tape, then affixed the inflated 260's to the tape.
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