pic: 4 inch Wheel Render

[JamesCH95]

If you've got SW2010 with all the options, try running an FEA on it and what sort of loading it might see and what benefits/sacrifices are required to make it out of different materials. Solidworks Sim is butt-simple to use, very robust, and gives reasonably accurate answers.

For example, if you make it out of 7075 it could weigh significantly less than if it's made out of 6061T6 because of the strength advantage of 7075. What about 2024?

Could you make it out of steel and weld it to an output shaft? Drilling a round hole is easier than broaching, and a welded shaft can be incredibly strong. You could use an alloy steel like 4340 or 4130 that has a strength/weight ratio that's better than most aluminums. I know it's harder to machine, but you might need fewer spokes for the same strength, so there would be less machining required.

I'd do these just as a exercise in SW (think about setting up different configurations for the same model too) but if you like where it's going don't be afraid to break out of the typical FIRST rut of "pretty machined aluminum everything".

Edit: also, the rendering looks really nice :-)