Above ideas sound great for your purpose. If you want to continue with your original idea, but with the 'floating' center square as I described above, here's how: Given your 8" squares for the center, cut 7 5/8" squares (2 for each center), divide on the diagonal, and apply to your original squares. For me the easiest way to center the triangles on the squares was to iron all pieces in half and use the fold line. My test square ended up just 12.5 ". Hope this helps; in any case thanks for the challenge to my aging brain! --nanibi