A Stackable variant of http://www.thingiverse.com/thing:28237 made through trial and error adjustment of the OpenSCAD file.

The aim is to make a 1m tall fountain bicycle powered fountain for the Night of Art and Science on June 6th 2015.
http://www.denachtvankunstenwetenschap.nl/acts/spinning-sculptures-helixfontein/

For anyone with a similar idea, you might want to check out this OpenSCAD library:
http://www.thingiverse.com/thing:777936