We wanted to avoid using toxic chemicals so we used baking soda mixed with lemon juice. We applied it to the rust with a chip brush and then let it dry overnight.
Then we took a wet abrasive sponge and began using some elbow juice to remove the rust. We were quite impressed at how the rust came off.
Here's the video we made showing the steps we used. We will post in another blog, the video and steps to add the faux wood finish to the shed.