Definitely aluminum foil! This was past down to me by my grandfather who was a blacksmith and machinist by trade. The small aluminum chards will fill in the rust pits as you are removing the rust. I uses a little chrome polish to lubricate the foil and then finish with a good wax. Not permanent, but it will help to delay further rusting.
Tim
Last edited by fixit1958; 11/07/2017 1:55 PM.