So, I picked up an old bike recently. Well, 10-15 years old -- not an antique -- and while it's in pretty good shape, some of the frame has rust, such as around the dropouts, the supports for the seat (it's a recumbent), etc.

Most of the frame is still covered by the paint and is therefore in great shape, but in some places I assume the paint had a chip or hole or something and that let water in, which caused rust, which flaked off, exposing a larger area, etc. The rust seems pretty thin -- I don't expect the structural integrity of the frame to be affected.

So, my plan is to try and get all this rust off in these spots, then find some touch-up to re-paint those areas (I'm going for "not rusting again" rather than "pretty", though I'd rather have it look good rather than bad, though "less work" is a factor too) and then work on fixing up the rest of the bike.

Any advice on getting the rust off? Drill with wire brush, some sort of chemical, SOS pads, something else? Is it critical that I get all the rust off before covering with paint?