What is the best way to remove rust from outoor metal?

The metallurgist says: The easiest way to remove rust is to eat it with acid. <a href="http://www.cmstestdenver.com" rel="nofollow">http://www.cmstestdenver.com</a> Phosphoric acid (H3PO4), will do nicely, and is so non toxic, you drink it routinely. It is available in your convenience store as Pepsi, Dr. Pepper, or Coke (read the label if you would like to check it). Vivianite, a naturally occurring rock is the result of Iron oxide and Phosphoric Acid. It's chemical structure is Fe3(PO4)2. The byproduct of the rust reaction is water. The chemical reaction looks like this. FeO + H3PO4 -> Fe3(PO4)2 + H2O Industrial strength method: NAVAL JELLY, available at ace hardware is concentrated phosphoric acid (H3PO4) and will work much faster without the hassle of sugar cleanup. DO NOT leave it on the surface for more than 15 minutes or it may structurally do damage. Remember to neutralize the runoff: To ensure no damage to plants or surroundings, sprinkle a little base, like baking soda, in ...  more