Using VTL (vertical lathe) to machine a 52' diameter ring

Been cutting on this massive chunk of steel for two days now. It's actually a huge demo that me and a couple other guys are using to learn how to run the VTL at work. I have the mini funny car on top as a marker to keep track of each revolution while hand feeding groove cuts. The car is about an inch long, so use that to gage how big this part is.