Has anyone out there ever etched a circuit onto a hard disk drive platter?  I was thinking this might be a way to achieve my goal (get a spinning circuit while minimizing vibration), but of course there are a number of potential issues.
I don’t have a platter handy as I’ve destroyed all my old disks with thermite, so I have no idea if the surface is even conductive.
Over the years platters have been made out of a multitude of materials, including fiberglass cores, glass cores and aluminum cores.  Fiberglass ones are probably pretty damn hard to find these days, glass cores would probably be super hard to drill any through holes/vias in without shattering and aluminum may not be electrically isolated from the magnetic surface.  Not really sure about that.
So if anyone happens to have tried this before, I’d be real interested in hearing about your experiences.