Originally Posted by
Metaluna
But you don't really have the same diameter. The diameter will be a function of the number of teeth, which must be an integer. By making the teeth smaller, adding or subtracting a tooth changes the diameter by a smaller increment, thus you can get closer spacing between gears.. At least, I think that's the idea.
Smaller teeth on same diameter = more teeth. More teeth (like a 60/30 setup or something) allows for smaller changes than can be made currently. It's like 1 degree Fahrenheit is smaller, more precise than 1 degree Celsius. They boil at the same temp (same diameter or range), but Fahrenheit has more "teeth" on it's ring..