This is how we do charity quilts, using about a 12" gap. We do twins and fulls, however, we tie them, but they lay pretty flat and could be quilted. If you want a small-ish gap, a helper is needed! We roll the sides first, then roll from the bottom as tightly as we can. Once the quilt is turned, we use yard sticks to poke the corners out and make sure the batting lays flat.