Does anyone know where to find a pattern for this? I'd like to make one of those metal yard art spinners. I have not seen one except in pictures so can't figure out a pattern. I know it's made by taking a circle of thin copper and cutting some kind of compound spiral into it, then pulling it apart to "expand" the metal. I don't mean the kind that ends up looking like a corkscrew, nor the one that is concentric circles. The one I want looks like a sphere in outline, except you see "S" shaped metal strips connected to the top and bottom.

Thanks!