How about touching it in with phosphoric acid? (One trade name for this is 'Kurust').
Don't forget to degrease it first - that is, remove the wax you put on it.
Many steel frames were said to be 'Bonderized' which was a form of phosphating, and it's quite possible that's why your frame hasn't rusted already.
I would touch it in with paint afterwards. If you can find a matt or eggshell touch up colour it will be less noticeable than using gloss.
Edited
@DeletedUser started
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How about touching it in with phosphoric acid? (One trade name for this is 'Kurust').
Don't forget to degrease it first - that is, remove the wax you put on it.
Many steel frames were said to be 'Bonderized' which was a form of phosphating, and it's quite possible that's why your frame hasn't rusted already.
I would touch it in with paint afterwards. If you can find a matt or eggshell touch up colour it will be less noticeable than using gloss.