Brass will automatically start to tarnish if exposed to oxygen. The only way to prevent polished brass from tarnishing is to coat it with a layer of clear sealer that will prevent air from reaching the brass itself. Many brass surfaces come with this finish originally, but it can wear down over time.Click to see full answer. In this manner, can you lacquer over brass?Brass, like most other metals, tends to tarnish over time. Tarnish doesn’t actually damage the metal, but it is somewhat unattractive, especially on decorative items such as jewelry, light fixtures and nautical detailing. One way to protect your brass and keep it looking new is to apply a coat of protective lacquer.Also, how do you stop brass from corroding? Combine salt with just enough lemon juice to make a paste. Dip a soft cloth into the paste and polish the brass. Alternatively, for stubborn tarnish, dip a rotary-head tool with a polishing head into the paste and apply it to the brass harware at medium speed. Accordingly, how do you finish brass? First, remove old finish from the brass with a standard paint stripper. Once you remove the old clear coat, wash the brass with hot soapy water. Then polish the brass using a lemon or vinegar solution. Finally, apply a protective coating of oil or clear lacquer to the brass.How do you keep brass shiny? Instructions: Check to see if it’s really brass. Squeeze half a lemon into your bowl. Add your baking soda. Stir the baking soda and lemon mix until it forms a delicious smelling paste. Use a soft cloth and apply the paste. Rinse off the paste and dry. When you’re done, give the brass a really thorough rinse.