Since I am currently doing some renovation work in our house I was looking for a simple color mixer. 

Most of the stuff I found online was either looking like modern art or something which could power a helicopter in a SciFi movie I decided to design my own.
I did not use any propeller module for OpenSCAD but simply used some geometric elements in OpenSCAD. If you are curious have a look at the OpenSCAD file.

Use a piece of M5 threaded rod plus two M5 nuts to drive the mixer. 

It is suited towards small color buckets but I guess you can easily scale it up based on the threaded rod you use (e.g. use an M10 rod and thus scale it up by 200%) to make it usable for bigger buckets.