Spandex needs to be stretched across a fixed frame to get it flat. I guess if you could get a heavy enough solid bar and stretch the fabric across the bottom and stretched tight on the roller it might work. You would have to design your own tab tensioned cords on the sides to stretch it horizontally. The solid bar on the bottom would have to be very heavy and strong enough to hold the tension without bending. Interesting experiment. Just some suggestions maybe two 10' x 2" steel electrical conduit and fill the bottom one with sand or even lead shot for weight and use the top one for a roller. Sew some very strong nylon fishing line or thin steel wire into the side of the fabric for tab tension.
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