  A soap film is actually a thin solid fluid bounded by two surfaces of
opposite orientation. It is natural to model the film using one polyhedron for
each side. Two problems are to get the polyhedra for both sides to be in the
same place without canceling each other out and to model triple junctions
without introducing extra boundary components. We use chainlet geometry to
create dipole cells and mass cells which accomplish these goals and model
faithfully all observable soap films and bubbles. We introduce a new norm on
chains of these cells and prove lower semicontinuity of area. A geometric
version of Cartan's magic formula provides the necessary boundary coherence.
