How to Refinish Unlacquered Brass or Bronze Like A Pro
Clay and Steel Signature Bronze Gate Pull
Most hardware and metalwork you see with a brass or bronze finish is an ultra thin coating (1/10th to 1/20th of a millimeter in thickness) that is easily worn down over time. If you invest in solid brass or bronze finishing and refinishing the metal can be fairly easy and it will last for a lifetime. Think of it as similar to the difference between solid wood floors and laminate.
Before you get started I highly recommend doing test pieces on parts that are not likely to be seen before refinishing your whole item. There’s always a learning curve to these things, but the overall process is not too complicated.
This not intended to be a complete guide, as there’s books full of metal finishing and patina advice. This is just the simple methods that I use in my business.
How to spot unlacquered brass or bronze.
It is non-magnetic.
It changes color easily. If you have brass hardware, lighting or furniture it will turn a deeper yellow. Bronze tends to change a deeper brown and may even look a little pink. This is the best indication to me that you have real brass or bronze.
It’s not coated in plastic!
The extra shiny glossy topcoat makes care for that item easier, but plastics like polyeurathane offgas overtime, they break down into microplastics eventually and don’t allow for easy refinishing. I personally do use polyurethane on occasion when I know I need something that’s very easy to clean, like a table top. But, just like all plastics, I avoid using them whenever possible.
If you do have a brass or bronze item that is lacquered it is possible to remove that top coat, but first you will have to figure out the particular solvent for that top plastic layer.
The metal looks the same, no matter how deep you scrub
In an inconspicuous spot I would use a scrub pad or brass wire brush to scrub the surface until you see bare metal. If you scrub deeply the color should be the same throughout with no silver or grey colors showing through. If there are silvers or greys, you don’t have pure brass/bronze.
3M Scotch-Brite Pads Assortment
How to Clean Unlaquered Brass or Bronze
Cleaning is usually very easy!
You can use a green or white 3M pad. Depending on the texture of the finish you can start by simply scrubbing the surface with a scotch brite pad. Often that’s all you need to do!
A mirror finish on metal is more difficult. If you have a mirror finish the extra fine grey pads are 800 grit, but a mirror finish may be up to 3000 grit! So for extra shiny metal I would use a fine microfiber cloth and a chemical cleaning instead.
Use White Vinegar
For a chemical cleaning I begin with white vinegar. You can soak your parts in vinegar for an hour or two, checking the metal frequently. You can also spray your parts if you can not soak them.
For Extra Deep Cleaning Use Jeweler’s Pickle
For an extra deep cleaning I use copper pickle. This is a cleaning solution used often by jewelers. You can find it at most hardware stores in the pool chemicals section marked as PH Down. The chemical name is sodium bisulfate. When using copper pickle I use dish washing gloves and safety glasses in a well ventilated area. I use about 1-2T per cup of warm water. Soak your parts in PH Down, checking every 5-10 minutes. I find that my parts turn salmon pink if I soak them for too long. Or you can use a water bottle to spray it directly on your fixtures.
Rinse and Neutralize
After cleaning you can wash excess scotch brite grit off with water. I use water mixed with baking soda to neutralize any acid, including vinegar.
How to Finish Unlacquered Brass or Bronze
Clay and Steel Custom Bronze Seahorse Lamp
Wax It!
If you like a bare finish you can use Johnson’s Paste Wax, Beeswax for wood furniture or Renaissance wax to seal it. Unlacqured brass or bronze will continue to patina over the next few weeks. If any undesired colors develop you can scrub the surface with a 3M and wax again.
Oil It!
If you want to add a little shine to your bronze, I wipe a final coating of mineral oil onto the surface. You can do the same finish with brass but I find it isn’t as effective.
Try a New Patina
For cold patinas that can be done at home, the company Sculpt Nouveau has some great options. Patinas are advanced techniques requiring good ventilation and the proper PPE. Sculpt Nouveau has great online resource for using their patinas. You can see a brown to black patina using Liver of Sulfur here. Liver of sulfur has the sulfur smell or rotten eggs but is great for dark patinas.
The patina I use most often is Antique Brown. It works the best if you can soak the whole part in the patina, but you can spray it on in layers until you have the desired patina.
Seal it
After you rinse your patina I always finish with beeswax or paste wax. If you are using bronze you can finish with a coat of mineral oil.
