Chassis weight

[pmangels17]

Originally Posted by Chris is me

I think this is a really bad idea. Those hex shafts are designed to be used as spacers, not as drive axles. That part could easily fail when you need it the most.

Spend your weight where it matters. The drivetrain matters.

I think I misspoke, or you misunderstood me. http://www.andymark.com/product-p/am-superoptions.htm
The black plates seen in the image on this page serve as a spacer. We replaced those with this:
http://www.andymark.com/product-p/am-2241.htm
We didn't skimp on anything like a shaft. I misspoke when I called it shaft material. We did use it as a spacer. By using it, we saved a lot of weight.
When I referred to side plates, I didn't mean the main plates, I mean the other four sides, which I replaced with spacers. I apologize for saying it wrong.