Parametric Archimedes screw pump

This is the core of an Archimedes screw pump.

If you run the OpenSCAD file, you can adjust it in all sorts of ways.

It has a keyed lip at each end so that you can connect several in series for serious lift.

It also has a raised area in the middle to hold a bearing, such as https://www.thingiverse.com/thing:3311118 with an inner diameter of 64 mm.

You should print the short version first to make sure that the overhangs work well.

Inspiration and terminology from
THE TURN OF THE SCREW: OPTIMAL DESIGN OF AN ARCHIMEDES SCREW
by Chris Rorres of Drexel University
http://cicada.cs.drexel.edu/~crorres/screw/screw.pdf