With some good results, I have used on chips (especially on the rims) something which I think is called something like Scotch Brite. It is for kitchen cleaning, a green tight fabric/material that looks like steel wool. It comes about the size of a thin sponge. Sold in all large supermarkets in the kitchen sponge section.

Anyway, I vigorously rub this on the chip (wet or dry; try either way). Then I rinse off the chip, dry, apply some oil, dry with paper towel. Presto!