If you polish sheetmetal parts on a buffing wheel you better be extremely careful because the wheel can snag on something and pull the part out of your hand. Wear heavy leather gloves, pay CLOSE attention to what you are doing and go slow.
Back in the 70s we sent a thin stainless steel moulding that fits around the edge of a glass sunroof out for polishing. It was mounted onto a wooden fixture of sorts so it wouldn't get warped from the polishing. The guy doing the polishing put his head through the open center of the fixture, the moulding got caught in the buffing wheel and it cut his head off.
True, that's a bit extreme but just be aware that those things are not to be taken lightly.
