We used this exact same formula / recipe in boy scouts when we were kids and used HULA HOOPS for gigantic bubbles. We also stuck the tops of round garbage cans in it and played with the bubble skin. #science #crosslink #polymer #fibers #boundry #skin Note: It doesn't have to be Joy – joy just happens to be a very basic dish soap. Any soap will work. Also you can cut the recipe down smaller if you need to.