Mechanical Surface Preparation Methods
An abrasive may also be used to remove the protective film. If there are impurities embedded in the metal, a deeper cleaner can be used. Just be gentle enough not to erode the brass surface and just remove the protective film and any impurities.
Large pieces or those that need a deep cleaning can be sand blasted or bead blasted.
Surface impurities can be rubbed off using a kitchen abrasive scrubbers such as Scotch-Brite® pads, copper mesh or steel wool that are typically used to scrub pots and pans. There is a delicate balance in scrubbing too hard and removing too much brass. These methods are more applicable for larger pieces or those that need a deeper cleaning.
For smaller pieces or those pieces that need minimal surface preparation, a gentle polishing may be all that is needed. A mixture of water, vinegar and flour makes a mild abrasive from material available in the home. Toothpaste is a mild abrasive that may also be used. Polish the piece with a soft cloth or use a toothbrush to reach engravings or crevices.
After surface preparation, once again, handle with care to avoid getting dirt and oils on the clean piece. Now that the piece is thoroughly clean and ready, you are ready to learn how to antique brass.
Here is a YouTube video on removing lacquer from brass: