SA: How do you make a balloon?
JP: An artist makes a pencil sketch and then turns it into a 2-D scale computer drawing. Artists use the scale drawing to build an armature, which is like a metal skeleton. They add clay, sculpting it to look exactly like we want the character to look in its flying pose. Then we make two rigid molds from the clay. We paint one mold to look just like the balloon. The designers draw all the technical information on the surface of the other mold. This becomes the blueprint for the balloon. We translate this information to create patterns for the fabric that will become the balloon.
SA: What science is involved in making sure the balloons float?
JP: You have to work out the physics of the weight of the fabric and the paint versus the lift of the helium inside the balloon. The smallest balloon we can make is a 10-foot-diameter sphere. Anything smaller won’t float because the helium won’t have enough lift to counter the weight of the fabric and paint.