Customizable Shredder Blade

This is a customizable blade for a shredder, like the one in http://www.thingiverse.com/thing:356580. You can set:
* the number of teeth
* the angular width of teeth
* the radial depth of teeth
* the pitch of the teeth
* the nut trap shape and diameter
To use with a CNC, download the file, and run the program with thickness=0. This should create a 2D file that can be exported to DXF.
Currently there is a bug using number_of_teeth=3 and 5, at least in OpenSCAD.
EDIT: Teeth now have more material behind them, due to a 4 point tooth.
EDIT(2014-07-16): fixed (read "hacked") bug for 3 and 5 tooth blades.