What of electro polishing? I rigged a small unit in my garage to clean up some 316 SS parts I had made. I used some metal prep (main ingredient phosphoric acid) for the solution. This particular stuff also had detergent in it and it foamed like the washing machine in an old sitcom.
just call me Lucy. There are some write ups of the base procedure on the web.
What I describe won't make it really shiny but it does remove crud where you won't need as much elbow grease to get real shiny.