OpenSCAD Helical Gears

This is the second half of my http://openscad.org gear sets.

I couldn't get the top and bottom parts of the double helical to union properly, so I ended up offsetting the bottom piece by 0.1mm :( It skeins and prints fine though.

This thing is part of a set:
- spur gears: http://www.thingiverse.com/thing:1336

UPDATE: I'm printing some gears and noticed a couple mistakes on the openSCAD script: the variable 'orientation' wasn't doing anything and the value 'extrudeInDiam' was in fact being used as radius. They're both fixed now and I uploaded a new version of the script.