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.