I'm sorry. I don't mean to beat a dead horse.
I don't know how to read the chart, however, I did cut two 6 1/2" squares, sew them around all sides, cut in quarters diagonally, press open, sew them together and got an 8" pinwheel. ok, I get that.
What I don't understand is the math. IF I want to end up with a 6" pinwheel (all 4 pieces sewn together, but not sewn to other blocks, how do I figure out what size squares to start with before any sewing around the perimeter. (let's say my quilt top is going to have a 6" solid square, then a 6" pinwheel block, then another 6" solid square, and another 6" pinwheel block.. you get the idea)
Thank you. (this is going to be a post and run. it's midnight here!) I'll check back tomorrow.