Making the Olympic Rings out of a segmented assembly. 30" rings and 3 layers (2 1/4" thick). Took me weeks and dozens of hours. It was just a party decoration (a huge one!). I could have just cut the outline from a sheet of 1/4" plywood and no would would have noticed. As I told my friends "A complete waste of time". Now it's stored in the rafters of my garden shed.