The mosaic was 50"x40", and the routine was fairly standard. I pre-built some of the mosaic before the show, shipped it to the show, and then showed up on-site to finish it.
The only real hiccup came on the first day, right when I arrived to make sure all of the materials had shown up. Over the period of a couple of months when the project was first discussed, someone on the project team forgot the ensure that the back wall upon which I would hang the mosaic would be plywood or some other sturdy material.
Instead, that back wall of the booth, upon which a 30 pound mosaic was to hang, was only 1/8" foam-core-ish material. Fortunately, the set-up guys were able to double up its thickness and supply me with nuts, bolts, and washers (to replace the wood screws I'd brought). With a little ingenuity, all worked out fine.
In fact, the build went quite quickly. Since the design of the image comprised large areas of same-color pieces, I was able to complete the mosaic with absolutely no worries about the Tuesday afternoon deadline.
While I was building it, tradeshow attendees were invited to guess the number of pieces I was using in its construction (the person who guessed closest would win a $50 gift card or something).
As always, the demonstration drew a lot of attention to the booth.
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