Hi there! I have a pinwheel math question for you. I used two Moda charm packs to make "fast and easy pinwheels" from the Missouri Star Quilt company. If you have not seen it, it is ingenious. You lay two charms together, light and dark, and sew 1/4 inch around the entire charm. Then you just cut them diagionally from one corner to other, both ways. Sew the four pieces back together and what I am left with is about a 5 3/4 inch pinwheel. They turned out pretty well, only a few points that didn't match up as planned.

What I would like to do is sew one same fabric triangle, to every side of each of my blocks so that I will have a bigger block, and the pinwheel would be on point. If my blocks are all about 5 3/4 inches, how big do I need to make the triangles, so that 4 triangles sewn together will be the size of my pinwheel block? Is hard to keep it from getting all wonky?

Thank you in advance!

~Karen