[msimon785]

What do you mean by "Does FIRST require us"?
FIRST doesn't regulate what you do in Inventor. They don't care if you use Inventor. Many teams use SolidWorks or ProE. Furthermore, FIRST doesn't care if you choose not to CAD at all. If you are referring to Autodesk for the Excellence in Design challenge, of course they *prefer* that you use the tools that they implemented in their software.

The CAD team at 1515 strongly believes that it is crucial and most efficient to use whatever tools are available to their fullest potential. Use the Roller Chain generator. It's quick, dynamic, and allows for modification. If you don't like the blueish line (which I can't stand), open up the part and change the material to Metal Steel Oxidized.

I have tried, and it not only would take the better part of the build season to CAD a chain, but also it would be required to be designed around a specific sprocket DIA and distance. It is unforgiving.

EDIT: sorry, that came out a bit harsh. Didn't know you are a rookie. If you'd like, you can send me your CAD to take a look at. You are basically allowed to do whatever works best for you.