For rust removal, try 3M Roloc bristle pads, as shown below. Awesome to use, very fast, very forgiving, and give an excellent finish.
If you go on to do more you will probably want to remove metal.
Start with some carbide burrs. They remove metal at an incredible rate, but tend to chuck splinters everywhere so wear decent gloves and eye protection.
Slightly less severe are stones. They still remove anything, including hardened areas, but give a better finish. For finer finishing the rubber backed abrasives such as Cratex points are great.
Whatever you get, get decent quality. Die grinders are high speed tools and cheap accessories just won’t work. I turned up to do a job once, and one of the guys asked “why do you bother with those stones, they don’t work”? He’d only ever tried the cheap ones, which disintegrate almost instantly.
I advise obtaining a copy of the MSC catalogue. They sell all, the accessories, and most seem to be of acceptable quality!
