I went to Advance Auto to get a serpentine belt. I am currently working on a hood for my Camaro and wanted to get rid of the rust and do it right. I saw a product by Purple Power called De-Ruster. My hood had some surface rust from the rain we had the past 2 days and gave this stuff a shot. The picture is of the hood and all that is black used to be rust. I called the company to get info from a MSDS on the volume of phosphoric acid because it wasn't on their website and the lady told me is was around 70-80%!. I BELIEVE IT!! The call took literally 5 minutes and the hood was already rust free from the time I sprayed it until the time I finished the phonecall. If ya got rust try this. It was less than $7 a quart.

Ken

bear concreate etch n rust remover, paito section of lowes or......

$7-9 gallon, same powerful stuff. I mixed it 50/50 on most things.
Use straight on fresh hot weld, just don't breath. Makes em look nice.