But, if the arbor is loose it may require a thin shim around the shaft. And, be sure that the screws holding the arbor are "TIGHT". I place a thin bit of popcan folded into the screw holes before inserting and tightening the arbor screws. The screws should be showing almost no threads. That sorta protects the threads on the shaft.

If you hear a buzz....shut off the switch and duck. The buzz may mean that the arbor is coming loose.

And, an apron and face mask is a given!! if you have never buffed before, You cannot believe the stripe which immediately forms from the floor to the ceiling and includes you! the first time you load a buff with compound!!!

Do a "buffer wiki" search here on SRP for interesting ways of using one.