It seems to me that a mixture of Mario's idea to get the most basic shape down would be ideal; then using vskid's idea at varying heights to 'step' into the secondary curves would get things darned close, if taking a long time to do (and making sure the mold/case and stick-thingie are both stationary, and the stick-thingie dead center on whatever the halfway point is at that point in time). After that, it'd be down to sanding and strong eye work with some measurement work here and there.
Outside of that, all I can think of is 3d modeling to make the mold for the mold for the case. Or the mold itself. Or the case. However you'd need that done.
Tips for making SYMMETRICAL Vacuuform mould?
Moderator: Moderators