I love doing these! But i have an easier way of doing them....start with 2 fabrics facing each other and sew all around it then draw an x on one side and clip in the middle so u can get scissor thru to cut on diagonial line (x) press open and get another square which will be equal size of new block and do it same way as u started, squares will get larger til u want it to a certain size block. No triangles to deal with. But your idea is so pretty too!