How To Polish Brass: The Full Guide

With its warm golden hue, brass has been a preferred metal for decorative items, musical instruments, and architectural details for centuries. Nevertheless, brass requires a little maintenance to keep it looking good. 

Maintaining and polishing brass isn’t merely about aesthetics, though. Regular maintenance ensures the longevity of the item, whether it’s a cherished family heirloom or a recent flea market find. Plus, there's something undeniably satisfying about the process of transforming a tarnished piece into a radiant showpiece. In this guide, the team at Red Label Abrasives provides tips for keeping your brass items in top condition. 

Is Your Item Actually Brass?

Be sure the object is genuine brass before starting the polishing process. This step is essential, as the care and polishing techniques vary based on the material. 

Solid brass items are made entirely of brass. They are durable, have a higher resale value, and can be polished without much concern of wearing down the surface. Brass-plated items, on the other hand, are made of different base metals, like zinc or steel, covered with a thin layer of brass. The brass coating can wear off over time, especially with frequent polishing or abrasive cleaners. Special care is needed to ensure the plating remains intact.

Here are some tests that can confirm the authenticity of the item.

The Magnet Test

Take a magnet and place it on your object. Genuine solid brass is not magnetic, so if the magnet sticks to your item, it might be brass-plated or made of a different metal altogether.

Check for Markings or Stamps

Many manufacturers leave a stamp or marking indicating the metal type. Examine your item closely for any inscriptions or symbols. Items marked with ‘EPNS’ indicate they are electroplated nickel silver, which means they are not solid brass.

Examine the Color

Genuine brass usually has a bright, gold-like appearance. Over time, tarnishing might give it a darker patina, but underlying hues remain gold-like. With brass-plated material, the base metal might show through in areas where the plating has worn off, revealing a different color, such as silver or copper.

Weight

Genuine brass is a relatively heavy metal. If your item has some heft to it, it could be a sign it's made of solid brass. Brass-plated items tend to be lighter, especially if they're made with aluminum or tin bases.

Preparing to Polish

Start by gathering the right tools. They include:

• Soft Cloths: Microfiber cloths or soft cotton rags are ideal. They won't scratch the surface and are excellent for applying polish and buffing.
• Brushes: For intricate brass items with detailed engravings or patterns, a soft-bristled brush, like a toothbrush, will help you reach crevices and nooks.
• Wet sanding abrasives: Either sheets or discs depending on the size of your workpiece and your preferences. 
• Polishing Compounds: Depending on your preference, gather commercial brass polishes or ingredients for homemade solutions. (We'll review specific polish choices in later sections.)
• Rubber Gloves: Especially if you're using commercial polishes, gloves protect your hands from chemicals and avoid leaving fingerprints on the freshly polished brass.
• Safety Goggles: If using sprays or when there's a risk of splashing, it's always a good idea to protect your eyes.
• Mild Dish Soap: For a gentle cleaning before polishing.
• Basin or Bowl:To hold soapy water if a preliminary clean is needed.

When working with chemicals, even those in commercial brass cleaners, always ensure you're in a space with good airflow. This helps in avoiding the inhalation of fumes that could be harmful. You should also lay down newspapers or plastic sheets to protect your working surface from any accidental spills or drips.

Cleaning Brass Before Polishing

Brass objects, especially those frequently touched or exposed to open air, tend to accumulate dirt, grime, and tarnish over time. Proper cleaning ensures that the polish can work on the brass surface without any interference.

Removing Dirt and Grime

Fill a basin or bowl with warm water and add a few drops of mild dish soap. Dip a soft cloth into the soapy solution and gently wipe your brass object. For items with crevices or intricate details, consider using a soft-bristled brush like a toothbrush. The mild detergent helps break down the oils and dirt accumulated on the brass, ensuring a smooth surface for polishing.

Removing Tarnish

Mix equal parts of white vinegar and salt in a bowl to create a paste. Vinegar acts as a mild acid, helping break down the tarnish, while salt serves as a gentle abrasive to lift the tarnish away without scratching the brass.

With a soft cloth, apply the mixture to the tarnished areas of your brass item, rubbing gently in a circular motion. If dealing with more stubborn tarnish, you can let the mixture sit on the brass for a few minutes. Rinse with warm water.

Drying the Brass Thoroughly

Any residual moisture can lead to spots or hastened tarnishing. It's crucial to ensure the brass is completely dry before proceeding to polish. You can either lay the item on a soft towel in an area with good airflow, allowing it to dry naturally, or using a soft, lint-free cloth, pat down the brass item to remove excess water, then gently buff until it's completely dry.

Sanding Brass

You’ll need to strip and sand the brass before you can start to polish it. Carefully examine the condition of the brass. The extent of damage or wear will determine the grit level of sandpaper you should use. For brass that's seen better days or has significant imperfections, start at a  lower grit (around 320 grit). On the other hand, if your brass is in relatively good shape with only minor blemishes, you can start with higher grit (around 800 grit).

The Sanding Process

Wet sanding is a technique highly recommended when working with brass. It serves two purposes: minimizing the spread of sanding residue and creating a remarkably smooth surface. If your goal is to achieve a mirror-like finish, wet sanding is essential. As you proceed, apply gentle but consistent pressure on the wet sandpaper, preventing accidental scratching or indentations in the metal.

You’ll want to use a grit progression starting at around 320 or 800 (depending on the condition of the brass) and work your way up to around 1500. Hand sanding can be ideal for small brass items, but it would be quicker to sand larger pieces with power tools like a disc sander. Red Label sells waterproof film sanding discs that you can use for wet sanding. 

Choosing the Right Polish

The right polish not only intensifies the metal's innate luster but also leaves a protective layer, ensuring that the shine endures. Here's an overview of your choices.

Commercial Brass Polishes

• Green Rouge Buffing Compound: Green rouge is a top choice for those aiming for a high luster on metals, notably aluminum and stainless steel. It illuminates both hard and soft metals while providing ample cut to eliminate minor blemishes and scratches. The finish achieved with green rouge tends to be more luminous than that with white rouge.
• White Rouge Buffing Compound: White rouge is valued for its exceptional final finish on hard metals and gentle cutting action on softer ones. To attain the desired finish on a variety of metals like steel, iron, nickel, brass, copper, chrome, aluminum, and more, pair it with yellow buffing/polishing belts.

Besides Green and White Rouge Buffing Compounds, other renowned names in the market include Brasso, Wright's Brass Polish, and Weiman Brass Polish. Always heed the manufacturer's directions and safety guidelines.

Homemade Polish Solutions

• Lemon and Baking Soda: Mix equal parts of lemon juice and baking soda to create a paste. Apply with a soft cloth, rubbing gently, then rinse and dry. The acidity of the lemon juice combined with the mild abrasive quality of baking soda effectively tackles tarnish.
• White Vinegar, Flour, and Salt:Create a paste using equal parts of white vinegar, flour, and salt. Apply to the brass, let it sit for about an hour, then rinse with warm water and dry. Vinegar's mild acidity, combined with the gentle abrasiveness of salt and the binding properties of flour, helps lift tarnish and clean the brass.
• Tomato and Ketchup: Apply a thin layer of ketchup evenly over tarnished areas of the brass using a soft cloth. Allow it to sit for 10 to 30 minutes. Gently scrub with a soft cloth or soft-bristled brush, then rinse thoroughly and dry. The natural acidity of the ketchup dissolves tarnish, restoring the brass's shine.

Considerations for Antique or Delicate Items

If you're unsure about the age or delicacy of an item, always start with the mildest cleaning and polishing methods, such as soapy water or lemon juice without baking soda. In some cases, you may want to avoid abrasive cleaners: antique items can have a thin layer of brass or a delicate patina developed over the years, and using abrasive materials or strong chemicals can damage these.

The Polishing Process (with Commercial Polishes)

Using polishing compounds, especially specialized ones like the green or white rouge buffing compounds, can lead to outstanding results on brass. Follow the steps below to use these compounds to achieve that sought-after shine.

Step #1: Get Prepared

Put on safety goggles and gloves. Polishing can lead to small particles being dispersed, and it's always safe to protect your eyes. The gloves will also prevent oils from your skin from transferring to the brass.

Step #2: Choose Your Tool

If polishing manually, you will need soft, lint-free cloths or microfiber rags. For larger items or for a more professional finish, a rotary tool or bench grinder fitted with a buffing wheel is ideal. Ensure the wheel is clean and free from residues of other compounds.

Step #3: Apply Compound

For manual polishing, rub the compound onto the cloth to get a generous amount, then apply it to the brass in circular motions. If using a motorized tool, apply the compound to the buffing wheel, ensuring even coverage. Turn on the tool and gently press the brass against the moving wheel.

Step #4: Polish the Brass Surface

Apply steady and even pressure while polishing. This ensures an even shine. Using circular motions helps reduce streaking and ensures more thorough coverage.

After the first pass, inspect the brass item. If there are still areas that lack luster or have imperfections, consider a second application of the compound.

Step #5: Finishing Touches

Once you’ve achieved the desired shine, use a clean cloth to wipe off any residual compound. Consider applying a light coat of mineral oil or a commercial protective spray: this can help delay tarnishing and protect your brass item.

Protecting and Preserving the Shine

After investing time and effort into polishing your brass, the next crucial step is preserving its lustrous shine. Here's how you can keep your brass items looking their best.

Lacquers

A clear coat of lacquer can effectively seal brass, providing a protective layer against moisture, fingerprints, and air. Available in spray or brush-on forms, lacquers are suitable for larger items or those that won't be handled frequently. 

Before applying, ensure the brass is spotlessly clean and free from any polishing residues. Apply in a well-ventilated area, and follow the manufacturer's instructions for the best results.

Waxes

Waxes, especially those specifically designed for metals, can act as a barrier against tarnishing agents. They’re an excellent choice for frequently handled items, as the wax can be reapplied easily when needed.

Apply a thin coat of wax using a soft cloth, let it dry (as per product instructions), and then buff it to a shine. This not only seals the brass but also adds an additional layer of shine.

Storing and Maintaining Brass Items to Prevent Tarnishing

Brass tarnishes more quickly in humid conditions. Store your brass items in a cool, dry place. For items that aren't used daily, consider wrapping them in acid-free tissue paper or soft cloths. This protects them from dust, moisture, and scratches. For items stored together, like cutlery, ensure they don't touch each other directly. This reduces the chances of scratches and tarnishing.

Other recommendations:

• Use a soft cloth to regularly dust your brass items. This prevents grime build-up which can accelerate tarnishing.
• If you've sealed your brass with lacquer or wax, avoid using abrasive cleaners. Instead, gently wipe with a damp cloth and dry immediately.
• Over time, wax coatings might wear off, especially on frequently handled items. Reapply when you notice the shine diminishing or the brass starting to tarnish.
• When handling brass, especially polished and unsealed items, try to wear gloves or wash your hands prior to handling to reduce the transfer of oils and acids from your skin.

Common Mistakes to Avoid

Like many restoration and maintenance tasks, polishing brass can be risky when not done correctly. Here are some common mistakes and how to avoid them.

• Over-Polishing: Excessive polishing can wear down the metal over time, especially if the item is an antique or has intricate engravings. Only polish brass when it's visibly tarnished. Instead of frequent polishing, focus on regular cleaning and protection methods to maintain the shine. 
• Using Harsh Materials: Using abrasive pads or harsh chemicals can scratch the brass, leaving it looking dull and, in some cases, irreversibly damaged. Always opt for soft cloths, like microfiber or lint-free rags, when polishing and use a product designed for use on brass. If in doubt, always perform a patch test on an inconspicuous area before applying any product or method to the entire piece.

Polishing brass is as much about avoiding mistakes as it is about the right techniques and products. Understanding these common pitfalls and adopting preventive measures can ensure that your brass items remain in good condition for years to come.

Red Label Abrasives - a Cut Above the Rest

With appropriate care, your brass items and fixtures can maintain a flawless gleam for years to come. Abrasives and polishing and buffing compounds play an important role in keeping brass in top condition.

For those seeking a quality product, Red Label Abrasives offers top-of-the-line wet sanding sheets, wet sanding discs, and polishing and buffing compounds. Our abrasive technicians also have the expertise that can help you get the most out of your purchase. If you have questions or would like to place an order, call 844-824-1956 or fill out our contact form today!