One of my first booms I made a disappearing pinwheel block and miss cut (also miss sized the original large pinwheel) anyway didn't have enough of the main fabric. I forget exactly where I added the extra fabric (but think I remember to the outside of the big pin wheel) and added a coordinating fabric. Anyway when the dust settled I had a disappearing pin wheel that had a contrasting + plus sign built into the block turned out even better then originally planned.