RodBot 3/8" SAE (Imperial) Frame

I've slightly modified two of [sandberg's original RodBot STLs](http://www.thingiverse.com/thing:145089) to allow for use with 3/8" threaded rods, as 10mm ones were not sold at Home Depot.

I'll be trying 5/16" threaded rods in place of all of the other 8mm ones.