Chemical stripper is a great starting point but every time I've stripped an old frame there was corrosion under the finish so it's not as if you are going to get away with stripper alone. If the paint is "the good stuff" some high power stripper like that Jasco Professional is great because it's much stronger than the weak sauce strippers like that citrus stuff. The good strippers used to require mineral spirits to remove whereas the weak stuff used water. Unfortunately, even the good stuff is weaker than it used to be. Anyway, mechanical rust removal, and removing paint down into cable stops and the like is typically part of the bigger job. Dropping the frame into a blast cabinet at that point speeds up the job greatly if you are fortunate enough to have one. Some phosphoric acid also works great to remove rust. Jasco Etch and Prep, available at Home Depot, is fantastic stuff and highly recommended.

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