Quiltforme (on this site) has done one she called "pinwheel disappearing 4 patch" and she gave the coloured photos of how to do it. I did a square to try it and it is easy. I did big squares about 16" (they get cut a few times) and it looks like a lot of work but it isn't. I would copy it to here but don't know how; but if you type it in on the search area up on the top of the page it will come up.