A similar methodology is already in commercial use for precision mechanical polishing. Of course there are ferromagnetic seals for vacuum, but dynamic methods

A similar methodology is already in commercial use for precision mechanical polishing. Of course there are ferromagnetic seals for vacuum, but dynamic methods have been utilized for about 10 years. https://www.sciencedirect.com/science/article/abs/pii/S0141635914002001 https://www.sciencedirect.com/science/article/abs/pii/S01416... https://www.asphericon.com/en/blog/detail/high-end-finishing-2-magnetorheological-finishing https://www.asphericon.com/en/blog/detail/high-end-finishing...