New brass has a bright golden color, but over time it tends to develop a dark, brown, green or reddish patina. If you prefer the look of antique brass, there are many techniques that allow you to speed up this normal process or even imitate its effects. Continue reading this tutorial to discover the method that best suits your purposes and to learn how to prepare the metal so that the result is perfect.
Steps
Method 1 of 4: Preparation
Step 1. Make sure the object is made of brass
There are some metals that have a similar appearance to brass, but react differently to these aging methods. Incorrect treatment could corrode the object, so take it to an antique dealer or other expert, if you are unable to identify it yourself.
- Clean brass has a bright and golden appearance. The metal that resembles it the most from an aesthetic point of view is copper, which has brown and pink shades, and bronze, which instead has more brown and dark shades.
- Brass has a slight magnetic conductivity, but should only maintain contact with very strong magnets. If a small magnet sticks firmly to the surface, it is probably another metal plated with a thin layer of brass.
Step 2. Learn what to do if your item isn't brass
If you're dealing with a different brass-plated metal, then try a gentle technique, such as vinegar or salt water, as more aggressive solutions can corrode the thin plating layer. If it is copper, read the instructions in this article. If the material turns out to be bronze, you can buy a specific "burnisher" and follow the steps in the "With an antiquing solution" section.
Step 3. If the brass is lacquered, remove the finish with nail polish remover
The lacquer for brass is a layer of transparent and hard material that protects the metal from oxidation, the very process you want to imitate or facilitate. Apply nail polish remover containing acetone to the entire object to remove the lacquer.
- Wear rubber gloves and work in a well-ventilated area to avoid inhaling solvent vapors.
- If it is a small object, leave it to soak in acetone.
- For large objects, use a brush to spread the solvent over the entire surface. Be careful not to forget any corner.
- Alternatively, you can use methanol, a paint stripper or a lacquer thinner.
Step 4. Once the metal has been treated with acetone, pour very hot water over it
Wait a few minutes or until the hairspray begins to flake or melt like a sticky mush. At the end, wash the object with very hot water to remove any residue.
Check that all the lacquer has been removed. Modern objects made of brass are often treated with a thick layer of finishing that requires several attempts before being completely eliminated
Step 5. If there is no finish or the lacquer layer is very thin, then wash the material gently
If you feel it is greasy or has a thin protective film on it, you can probably just wipe it with a cloth soaked in denatured alcohol or a 50% solution of water and vinegar. If the object is not treated at all, wash it with soap and water anyway to prepare it for the aging process.
Wear gloves even when using non-aggressive products on the skin, since the sebum present on the hands could fix on the brass and interfere with the aging process, making the result uneven
Step 6. Dry the metal completely before continuing
Do not start treating the brass until it is completely dry. Use a hair dryer, propane torch, or even an oven to speed up this step.
- Be very careful when you apply heat to the brass you have just removed the lacquer layer. If you have forgotten any trim fragments, they can catch fire or release toxic vapors. Dry the brass in a well-ventilated area free from flammable materials.
- At this point you can do one of the methods described below. If you don't know which one to try, read the first step of each to understand the pros and cons.
Method 2 of 4: With Salt Water or Vinegar
Step 1. Use vinegar or salt water to age the brass in a simple and safe way
You can use any type of household vinegar or even table salt. This method takes longer than the others (several hours for vinegar, up to a few days for salt water), but saves you from handling dangerous chemicals, as well as allowing you to use materials that are probably already in the pantry. your kitchen.
- First prepare the brass as described in the previous section, to be sure that the procedure takes effect.
- Wear rubber gloves to prevent (as explained above) oil from settling on the metal.
Step 2. Use salt water to slightly darken the metal
Prepare a solution in equal parts of water and table salt to oxidize the brass, so you accelerate the natural process to which the metal would still be exposed. Spread the solution with a small brush over the entire surface of the object and repeat the procedure every day until you are satisfied with the result.
Step 3. If you prefer an even older look, replace the salt water with vinegar
You can apply the solution with the brush or dip the metal directly into the liquid (any type of vinegar is fine). Wait for the object to dry and then apply another "coat" of vinegar, if you prefer a darker color.
- Mix a spoonful of table salt with the vinegar to give it a greenish patina.
- If you heat the brass with a hairdryer set at 230 ° C, you will get more evident results. Remember, though, to wear oven mitts or garden gloves to handle metal at these temperatures.
Step 4. For a warm color with shades of brown, use the vinegar vapors
This technique does not allow you to obtain realistic results like those given by ammonia or an antiquing solution, but some people love the "gingerbread" color that vinegar produces. In any case, it is a safer and less expensive procedure than the others.
- Pour some vinegar into a plastic bucket with an airtight lid.
- Insert a block of wood or other similar object into the bucket so that you have a stable, dry surface above the liquid level.
- Place the brass on the dry surface.
- Seal the bucket with its lid to trap the vinegar vapors, so that they can alter the appearance of the metal. Wait several hours or all night.
Step 5. Regardless of the technique you used, at the end wash the brass with warm water and then dry it
When you have achieved the desired result (several applications may be required), wash the metal and dry it with a cloth or heat.
Once dry, you can decide to protect the color obtained with a lacquer or brass wax
Method 3 of 4: With an Anti-aging Solution
Step 1. To quickly antique brass, buy a specific solution
This is the fastest of all methods, but requires the purchase of an ad hoc product. It is usually labeled with the name of antiquing or burnishing agent for brass. The specific brand determines the final appearance of the object, however the process to be followed does not vary.
- Before you begin, always proceed to metal preparation as described in the first section of this guide.
- If you are not sure if the object is made of pure brass, this method is not the most suitable. Instead, rely on vinegar and salt water, as explained above.
Step 2. Put on rubber gloves, safety glasses and work in a well-ventilated room
Antiquing solutions are made up of different chemicals, most of which can damage the skin, eyes or release toxic fumes. Protect yourself with basic safety devices and open the windows before proceeding.
Be especially careful if the burnisher contains these dangerous ingredients: ammonium hydroxide, glacial acetic acid, nitric acid, or sulfuric acid
Step 3. Dilute the product by following the instructions on the label
Read them with great care. Some browners do not need to be diluted, while others are so strong that the mixture needs to be prepared with water in a 10: 1 ratio. Use water at room temperature and a ceramic or plastic container large enough to contain, submerged, all the brass object.
- Do not use containers made of other materials, otherwise the acid solution will corrode them.
- Do not overfill the container. Leave enough space to add the brass object without the liquid overflowing.
Step 4. Move the metal object under the surface of the solution (wear gloves
). Keep it immersed in the liquid and keep moving it to get rid of air bubbles. Make sure that the solution covers the entire surface of the metal, but be careful that it does not enter the opening of your gloves.
- The air bubbles that remain attached to the surface of the brass prevent the burnisher from acting, consequently, if you do not continue to move it carefully, you will get an object with non-antiqued dots.
- Turn the object to make sure it is evenly exposed to the antiquing solution.
Step 5. Monitor the color change and remove the metal from the liquid when you get the hue you want
It may take only a few seconds or a couple of minutes before the reaction is triggered and the object goes from pink to red, to brown or black. When you notice that the brass has taken on the look you like, remove it from the burnisher.
- If you want to illuminate the object with golden reflections (see the next steps), wait for it to become a little darker than planned.
- Don't be afraid of ruining the brass. If you have removed it from the burnisher too soon, you can safely put it back to soak and shake it again. If you've waited too long, scrub it with a scouring pad or steel wool to remove the color, so you can try again.
Step 6. Rinse the object, if you want to give it luminous reflections (optional)
Use hot water and eliminate the white powder that is generated by the reaction with the help of a sponge or a scourer for dishes. In this way you will have a brighter metal and with a brighter hue, compared to the dark patina you obtained after bathing with the burnisher.
If you are looking to achieve a black (or almost) patina, you will get better and longer lasting results if you dip the brass in the burnisher 2-3 times, rinsing between one bath and the next
Step 7. Dry the metal evenly
When you are satisfied with the color, immediately dry the whole object. Areas that remain wet will be darker than the rest of the surface when dry. Use a rag or kitchen paper for this operation, as some of the color will transfer to the cloth.
Step 8. Treat the metal with lacquer or wax to preserve the hue you got (optional)
Apply a specific lacquer or other finishing product for brass to prevent the aging process from continuing. This step is highly recommended, especially if you have to handle the object often or if you want to keep the color you created.
Method 4 of 4: With ammonia vapors
Step 1. Apply ammonia periodically to achieve natural-looking aging
Ammonia is a caustic substance and should be handled with great caution, but it is the most effective of all to generate the greenish patina typical of antique brass.
- Over time, the ammonia evaporates from the brass, so you will have to repeat the process, from time to time, to restore the metal to its ancient appearance. The time required to complete the processing depends on the quality of the object.
- You will not get any results if, first, you do not properly prepare the brass as described in the first section of this article.
Step 2. Purchase ammonia and a sealable bucket from a paint shop or hardware store
You need "pure" ammonia and not a diluted household cleaning product you can find in supermarkets. In a paint shop you can also get the plastic bucket with airtight lid.
If the brass object is small, use a glass jar with an airtight lid instead of the bucket. Use a string to suspend the object over a small amount of ammonia and close the cap well, both to fit the string and to trap the vapors of the liquid
Step 3. Wear rubber gloves, safety glasses, and work in a well-ventilated room
Ammonia vapors are toxic and should never be inhaled. If possible, work outdoors or in a room with a lot of air circulation.
Step 4. Insert a block of wood into the bottom of the bucket
In this way you have a stable, flat and large enough "surface" on which to place the metal object. If it is a large piece of brass, create a plywood base on top of a stack of several wooden blocks to make it stable.
Step 5. Pour the ammonia into the bucket
Make sure that the liquid level is below the top edge of the wooden base. You don't need as much ammonia, although the more liquid, the faster the process.
Step 6. Place the brass on the "platform"
Make sure it is stable and does not run the risk of falling into ammonia. If this happens, retrieve the object with your hands protected by gloves and wash it with hot water. Dry it before putting it back in the bucket.
Step 7. Seal the bucket with the airtight lid, but check it periodically
Depending on the temperature and humidity of the environment, the freshness of the ammonia and the exact characteristics of the brass object, the aging process may take a few hours. Check every hour or so to check your progress, being careful not to inhale the vapors from the bucket.
Open the lid only enough to peek at the contents, then close it quickly so as not to disperse the ammonia fumes
Step 8. Wait for the metal object to dry in a well-ventilated area
When it reaches the color you want, let it dry naturally in the open air. If you love a shiny look, treat the surface with specific wax.
- The effect of ammonia is only temporary, so it is not necessary to add a layer of lacquer, since you would find yourself forced to remove it to subject the brass to a new treatment.
- You can use the same ammonia bath to treat other items, but not for an indefinite period of time. Ammonia, in fact, loses its strength and must be replaced with fresh product.
Advice
- Regardless of which method you have decided to follow, at the end (when the object is dry) you can apply a layer of brass wax or lacquer to prevent the metal from aging further.
- If you have laboratory equipment and some experience in the chemical field, you can also prepare an antiquing solution. Try it on a hidden corner before applying it to the whole object, as you could get negative results.
- Another technique for applying ammonia is to put the object in a garbage bag with a rag soaked in this liquid and then seal the container. This method is the simplest, but not the most recommended, as you may get an uneven effect if the weather is hot or humid.
Warnings
- Do not use a bleach-based or sodium hypochlorite product to age brass. This is a more difficult product to handle and more dangerous than those used in the methods described above.
- If you are not sure if the object is made of brass, take it to an antique shop or to an expert to have it identified. Bronze, copper, or brass-plated items deteriorate when subjected to an aging process for bronze.
- If a magnet sticks to your "brass" object, most likely there is another metal under the layer of this material. In this case, you can still antique the object, but you must be very delicate when you rub it and use small amounts of chemicals. Too aggressive techniques or solutions can corrode the plating and reveal the underlying metal core.
