I use the Rust Free. It is a mild solution of phosphoric acid and with a RED Scotch Bright will take most of the rust off. However, as you noticed there may be a dull gray color where the heaviest rust was. It really doesn't hurt anything and as long as it is not pitted, just leave it be. The Boeshield or a good coat of paste wax (non silicon containing) will help keep the rust away.
If you really get anal about having it shiny, you will have to buff the surface with a cotton/muslin wheel, or ball and polishing compound. If that doesn't do it, theeeeen!
The only other solution is to start sanding. Start with 100-150 and progress to 400-600 wet or dry and a lubricant. I use water ( then make sure it's dry), some use Mineral Spirits. The process is messy, but the end result should leave you with a bright shiny surface. ( I use an old 1/2 sheet sander).
Hi, sorry I missed you. I have gone to find myself, but if I return before I get back, please ask me to wait.
Nothing ever gets built on schedule or within budget.
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