I had never thought about welding a cage!! I have a welder. As far as the abilities, just read on it, practice, get good enough to make good welds (note, good welds does not necessarily mean nice-looking welds!) Steel is pretty pricey, but you can make it out of scrap steel, and some patience. That, and add gussets where joints meet/welds are made. Anybody interested in buying a custom-made squat rack or bench
??