Maybe he should price out some 1/4" A-36 plate, having it cut, jig made for it, welding... see if he can build just one and come out ahead.
I love the question where someone asked if you really had to use Carbon steel... steel by definition contains Carbon... not everyone is an engineer or has a metallurgy background I guess. Anyway, there are different varieties and standards. A-36 is construction grade low carbon steel. Good "general" stuff. Easy to work with and weld.
