I needed two beads printed and thought a simple solution was in order. With the power of the Customizer you can have any size bead you like. Oval as well as circular.

2/6/2016: Updated OpenSCAD file to work with Customizer again. At some point changes to Customizer caused the script to break.

In the customizer there is a slider bar to set the oval shape of the bead. 100 is circular. You can flatten or lengthen to your need.