Is rust an active thing? What I mean is, once rust developes does it take on a chemical life of it's own and keep eating your metal forever? Or if you, for example, put a coat of wax over some surface rust, does that stop it in its tracks?

I've got a Schwinn Le Tour III that's got spots of surface rust and a 98 Rockhopper with some internal rust (bb mostly). The Schwinn I went over the frame completely with wd-40 and scotchbrite, so it's looking as nice as it can without touch-up paint, and all I've done is wax it real good. On the rust spots I didn't sand them down to bare metal or anything, just cleaned them up as well as I could. Are they going to be static? Assuming I keep them coated in wax, the rust isn't still eating away under there, right?

And the rockhopper, there was enough rust to have some actual flaking in the bb shell. I've cleaned it out real good too- without going down to new, bare metal. If I frame-saver it will that stop the rust from growing (assuming it stays dry and clean)?