Customizable Delta Vase

Customizable Delta vase inspired by
http://www.thingiverse.com/thing:150482
from the original design by Mart van Schijndel
Generalised to N Sided Vase although rendering is slow for large N - NSides=20 took 30 minutes. Repetier Host called the STL non-manifold but Slic3r appeared to work. I'd be interested to know if it prints.
The current OpenSCAD code trims the bottom to assist printing.

More in my blog http://kitwallace.tumblr.com/post/93760445604/delta-vase