Acid and Copper Solution. 1  1. Ensure that the metal you are working with will rust. 2  2. Measure some hydrochloric acid into a plastic bottle. 3  3. Dissolve a bit of copper in the hydrochloric acid.  4. Dilute the copper and acid solution with 1  water. 5. Clean your steel or iron thoroughly.  6. Apply the acid 1  solution. 7. Allow the metal to  rust.
Quick Answer. Depending on size, potatoes should bake in the oven for around 50 minutes to 1 hour. Flipping the potatoes every 20 minutes during the baking process helps to ensure consistent baking throughout the entire potato. Continue Reading.
1 This allows steam to escape from the baking potato. 2  Bake the potatoes: You can bake the potatoes directly on the oven rack, or you can place them a few inches apart on a foil-lined baking sheet. 3  Bake the potatoes for 50 to 60 minutes. This allows steam to escape from the baking potato. 2  Bake the potatoes: You can bake the potatoes directly on the oven rack, or you can place them a few inches apart on a foil-lined baking sheet. 3  Bake the potatoes for 50 to 60 minutes.