I made one like that, but mine was a miniature quilt. I just used the snails trail block for the centres with the storm at sea sashing. My snails trail block was 3" finished and the sashing was 1". If you are planning on making a full sized quilt I would definately look at a fairly big block as there are lots of pieces in this pattern.
http://www.quiltingboard.com/picture...t-t208253.html