I really like using @Rhinoceros3d CAD software for 2D bike frame design and for simple 3D parts (like head tube badges). Rhino's command line and GUI interface is nearly identical to the @autocad industry standard and is very easy to learn. Plus the price is right at just under $1,000 for a full license that does not expire. Read more at www.denverbikeco.com/blog/why-i-like-rhino-for-cad-software.