When I was in college in Pensacola I worked some as a draftsman at the Westinghouse Nuclear Reactor plant. We had a vertical metal lathe used to turn the reactor cores that were made from stainless steel. As I remember (32+ years ago) it would turn maybe 24' in diameter and 32' tall. At that size it would turn only a few rpm's but the cutter speed on the outside was huge. Pretty impressive to watch in action, forgot the specs but it turned to very tight dimensions. Unfortunately the tree-huggers about put them out of business, but I still personally believe that nuclear power is what we will see in the future to partially solve the energy crunch that we will face. Not looking for a debate on that, it's just my opinion.