Kythera: Switching from Metric to US Customary Units

By default, despite the fact that most gear calculations in Kythera are unitless, the defaults assume millimeters.

Switching from millimeters to inches can be a little bit of a pain, since the defaults wind up being 25 times larger than reasonable. So here are some simple defaults you can use to set up Kythera to use inches instead of millimeters. Of course in your final design you will need to set these parameters according to the actual size of the components (such as axles and the thickness of the gear material) you intend to create.