Using Patina for Character on Brass Often times, old, antique brass is overlooked for its beauty in favor of fresh, polished brass. However, in circles of antique collectors, it is common knowledge that polishing off 100 years of patina can destroy the value of antique metal. A beautiful patina can add tons of character to a metal object, and this article will explain how to get this effect at home by utilizing various methods that have been tried and tested to be effective.
Before You Start: Clean The Brass Before you try to patina brass, it must be spotless and free of surface impurities. There are many ways to do this, but the best and most surefire way is to soak the part overnight in lacquer thinner or acetone. This ensures that all dirt, fingerprints, oil, and other impurities are completely dissolved. Another method I have used with some really good results is OxiClean and water. Just make a bath of OxiClean and water, and dunk your parts in the solution, and leave them sitting overnight or for a few hours. The parts come out clean, and OxiClean may also help start the oxidation process, which is needed for tarnishing brass and adding patina. Remember, if there are any weird splotches or colors on your brass object, they will be enhanced by the patina and become even more noticeable (unless you use the second method I describe below). You want to make sure your brass is as clean as possible, and handled as little as possible to get the best results.
The Ammonia Method There are many methods of chemical patina for making your brass look old. The most common method that can be used to add a professional touch of tarnish to your brass items is by using household Ammonia and a few other ingredients. You will need: One cup of hot water (not boiling) 1/4 cup of non-iodized salt One teaspoon of white vinegar - One cup of Ammonia (available at hardware stores) One metal or ceramic container large enough to hang your brass in without touching the bottom - A heat source
- The Method: Make a solution of your water, salt, and vinegar, and while the solution is still warm, generously paint a coat over the item you wish to antique or patina. This is basically a brine solution, which is commonly known to begin the oxidation process in metal, causing a patina to form over time. While the item is still wet with this brine solution, attach your hook to the brass.
- Next, pour your Ammonia into the metal can. Finally, hang the item into the can, while taking care NOT to let it touch the ammonia. The only thing left to do is heat the bottom of the can. This can be accomplished with a hair-dryer, heat gun, or similar. The goal is to get the ammonia vapors to contact the brass parts that are covered in the salt-vinegar solution. The ammonia vapors react with the brine solution and begin to immediately patina the surface before your very eyes. It may take several applications to get the results you want
- The results: The Ammonia method of tarnishing brass will cause the brass to start turning greenish brown. It may take some time to achieve the level of patina and oxidation that you want, but it can easily be achieved through this process - though it can be time consuming. If you really want to know how to patina brass, and how to save time and avoid the ugly green color, the next method will be faster and deliver more beautiful results that are hard to come by without 100 years of natural time and elements.
The Copper Sulfate Method The copper sulfate method of antiquing brass is the best I have achieved in my years of finishing metals, and this recipe is my own altered recipe from various sources. This is an excellent chemical patina that is easy to use to patina brass.
You will need: Eight ounces of water Three tablespoons of Novacan Black Patina (available online or in stained glass stores) One tablespoon of Novacan Copper Patina (same as above) One tablespoon of Miracle Grow pre-mixed flower food Heat Gun
The Method The ingredients above may sound foreign, but they are cheap and easy to come by. Novacan is only $3-4 per pint. You can alternatively substitute pure copper sulfate with mineral oil if you prefer, but the Novacan is the best material for the job that I have personally used. Mix all of your ingredients together in a can (for paint brush application) or in a spray bottle (for quick spray application).
- Heat your brass object with the heat gun until it is hot enough that water simply boils directly off of it. This is about the same temperature as a household iron. You should not heat your brass until it is glowing hot.
- When the brass is warm enough (this is achieved after 5 seconds of high-heat from my heat gun), apply your solution with a paint brush or with a spray bottle. The smell is horrendous, but the results are immediately visible. Best of all, you can completely customize the application intensity, size, pattern, and grain by continuing to add solution to the hot brass in alternating patterns (i.e. blotting the paint brush, stroking the brush, dripping the solution, etc.). By being able to completely customize the patina, you can create one of a kind patterns that look beautifully aged
- The results: This method will add a reddish brown color to your brass, but continued application can result in a brownish black color. While applying, it may appear that some spots are turning blue. This can be left alone if that is your desire, but it does not look natural nor professional in this application. The best way to fix this is to wipe the area with water, and then continue applying solution to hot brass until the blue starts to fade. When the brass is as dark as you would like it, wipe it clean with a wet rag (or with a thinner such as acetone) and you will notice less intensity. Also, when the brass is wet, it may look slightly more beautiful than when dry. You can keep the wet look by simply wiping some car wax (carnuba wax you use on your automobiles) on the brass. This is the most beautiful look I have ever achieved with brass patina
A side note about this method: Using Novacan Black Patina alone will immediately oxidize your brass, and will give you a blueish black patina. However, this is very difficult to accomplish without the brass looking painted or destroyed. Furthermore, this method is hard to clean without simultaneous adding a permanent luster to the patina finish. I do not recommend doing this for these reasons.
Other Methods I didn't Mention: There are some other ways to chemical patina or oxidize your brass at home, such as using liver of sulphur, store bought brass agers, and many other chemicals that are specifically made to patina brass. While these can be utilized for great results, sometimes the chemicals can be very dangerous, unstable, or expensive. It is best to gain some experience, in my opinion, using other methods before you attempt to use chemical patina solutions from a store. They can ruin your brass if you are not careful, and sometimes the results are a lot more permanent than other methods.
One Method I do Not Recommend Anyone Try: You can severly oxidize brass by placing your brass objects in a container of bleach, or bleach mixed with vinegar. However, this is a true oxidation, and not an effect. If you attempt this method, be advised that bleach may eat through brass objects, or create blackened pits due to impurities in the brass. Not to mention, this method may produce gases during the oxidation that will burn your eyes and lungs. Use caution when handling and using any caustic materials that may cause damage to you or your brass.
Any Questions? Hopefully, this article has helped you learn how to patina brass, how to oxidize brass, and how to tarnish brass properly, safely, and correctly. The look you want can be achieved at home cheaply and will look as if you paid a professional to do it. Do you have any other methods that you like to use that I didn't mention?