hi

i started off with the paper/cardboard mockup, works great if your doing things on the cheap/simple,

however, having recently upgraded to cad systems i can tell that they are really useful, i started off with sketchup (good for rough ideas) then i got solidworks (good mix of all cad systems) and now have autodesk (awsome) also having recently gained access to a cnc macine its good to have detailed diagrams.

arc welders are great, and tend to be a bit cheaper than migs

jack