Providing the frame is not cracked, you can either leave it alone and hope for the best or remove all the bubbled paint and underlying oxide with emery paper or similar, then repaint the bare areas with a metal primer and a suitable colour.
Short of a full sandblast and repaint, of course.
@yoav started
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Providing the frame is not cracked, you can either leave it alone and hope for the best or remove all the bubbled paint and underlying oxide with emery paper or similar, then repaint the bare areas with a metal primer and a suitable colour.
Short of a full sandblast and repaint, of course.