Saddle surface with level sets

thingiverse

This is a saddle surface with the vertical level sets. It can be printed without raft or support. It was created in Mathematica. Unfortunately the meshing was not ideal, so the level set at the middle produces some extraneous filament which has to be physically cut off at the end. Once done, however, it is quite a nice mathematical demonstration piece. For more information, see http://gmumathmaker.blogspot.com/2015/01/saddle-in-two-colors-level-sets-version.html