I had some loose buttons that made too much noise so I took off the rotor, put it on top of a vise. I then found a car wheel stud that had a round head, kinda like a ball pean hammer, and used it and a hammer to tighten up the buttons. Worked like a charm. Now that I think about it I actually used a tapered lug nut, a bolt and a washer. As I tightened down the lug nut it spread the back of the button. Good Luck