[eweinhoffer]

Molding parts with uniform thickness is tricky enough - without great tooling design and the perfect temperature/pressure settings, you'll get hot spots, flow lines and all sorts of visual defects in your part. Varying thicknesses make achieving these "Apple-like" levels of perfection in the plastics even more difficult, thanks to the fact that the material will cool and change shape at different rates.

[lwander]

Oh that's fascinating - thanks!