Quick Care Guide for Bronze Sculptures
Thank you for your recent purchase of a Gibby bronze. Even if you are not new to collecting bronze sculptures you may appreciate recommendations for the care of your bronze sculpture. I hope you find this “Quick Care Guide for Bronzes” useful.
I use Everdur silicone bronze 873 for casting all of my work. It is and an alloy made up of 95% copper. This is the most workable and most common of the highest quality bronze used in the fine art casting industry. Because there is such a high copper content, this means that it has the potential to oxidize and turn green. To deter this from happening within a short period of time, I seal all of my bronzes with Nicholas Lacquer to complete the patina coloring process while the bronze is still warm and mostly, if not completely, void of moisture. Then I follow it up with an application of a thin coat of carnauba based paste wax.
These two sealing processes are meant to lock in the chemical reactions and pigments created while creating the patina. This should get you off to a good start to maintaining your patina color.
I would like to mention here that like all fine collectibles, there would be an aging process that occurs to the look of your bronze. No patina stays the same exact color forever. Things will happen to the color of your bronze no matter how you care for it.
The question is how it will age and how quickly. The reasons for this, UV rays may break down the exterior seal on your bronze exposing it to the elements, which then break down the patina colors. Secondly, internal moisture from the environment can affect the patina from within. In addition, certain chemicals utilized in patinas have a tendency to continue to react over time. The most common of these elements is sulfur. Over time, and very gradually, you may notice that your bronze may appear a bit darker and often richer in color. This may be due to the amount of sulfur left on the piece in creating certain effects required for the patina. Other chemicals (which I try to avoid) might be considered less stable by nature and change color at a faster rate.
There are various preferences when it comes to how a patina ages. My goal with my work is to use the most stable methods and materials so that the patina ages gradually to reflect it’s true age and not prematurely. But there is only so much I can do after the bronze leaves my studio. So, for this reason, I have written this guide.
First of all, it is good to note that the bronze itself should last thousands of years provided that it is not blatantly abused or vandalized with heavy tools. The nice thing about bronze is that it has its own security system. If someone tries to hit it with something, it has a built-in alarm system and it sounds like BONG!!! So, there is no need to worry about the bronze disintegrating even in outdoor or underwater applications.
Second, UV rays kill patinas and it doesn’t take long in full sunlight. So the amount of maintenance depends on where you display your bronze. For instance, I have bronzes that I have never had to do anything with except dust. Even that was optional. And I have seen bronzes outside in full sunlight completely lose their original patina within a few short years because no maintenance was done to them. So consider where you will display your bronze to determine a maintenance plan. In general, indoor bronzes need very little maintenance unless they are right next to a window in full sunlight or near a close water source, like a sink or a fountain. All bronzes displayed outside need a regular maintenance plan involving cleaning and resealing. The nice thing is that it is not hard to do and depending on where you live in the world you may not have to do it all that often.
Quick and guide to the frequency of maintenance:
- Indoor and out of direct sunlight - almost no care involved
- Indoor but in direct sunlight - maintain every 6 months or so
- Indoors but near the ocean - maintain every six months or so
- Outdoors but not in direct sunlight - maintain every 6 months
- Outdoors and in direct sunlight - maintain every 3-6 months
- Outdoors and in or near water feature including sprinklers - maintain every 1-3 months
- Outdoors near the ocean and near a water feature - Enjoy having an antiqued green looking bronze.
Basic maintenance instructions:
- For indoor bronzes, lightly dust with a soft cloth, or spray with canned air.
- Use a fresh clean chip brush to brush a very thin coat of carnauba wax out of a can over the surface of the bronze. To avoid laying the wax down too thick, run the brush over the wax in the can then run the brush over the inside lid of the can to remove excess wax. If there is excess wax on the lid you can just use that wax for the next dip rather than going straight to the can.
Acceptable wax brands that I have used include Johnson’s Paste Wax, Trewax, Kiwi Neutral, Kiwi Tan, and Renaissance Wax. Johnson’s Paste wax is better for dark colored patinas and Trewax is better for light colored patinas. As far as I am aware, the other waxes are fairly universal with their uses but each has its strengths and weaknesses. But none of these will ever damage your bronzes and offer good protection from UV rays. You may contact me directly if you have any questions about specific wax characteristics.
- After applying the wax you may lightly rub the bronze with a soft non-abrasive rag to the level of shiny polish that you prefer. It is not necessary to rub the patina at all if you want more of a satin look to the bronze.
- Let the bronze sit overnight to see if any white-colored flakiness has appeared on the bronze. This means that the wax application is too thick. The easiest way to resolve this is to use a hair dryer turned up to high heat to melt the wax flakes to settle into the surface of the patina. Then lightly rub with a soft cloth again.
The process for maintaining an outdoor bronze is basically the same as an indoor bronze except for a few minor things as follows:
- You may need to do a more aggressive cleaning on the bronze since there is more likelihood for more extensive dust and dirt residue with special gifts left behind by birds. To clean the bronze fill a bucket of water with very diluted AJAX soap flakes. Some dish soaps will get the job done, however since they are degreasers they may leave a light residue on the surface of the bronze. With a gentle touch wipe over the soiled areas to remove debris. Rinse the entire bronze with fresh water.
- Let the bronze fully dry in the sun until it is warm. The warmth of the sun will help the wax flow into the pores of the bronze to help lock the patina into place.
- When the bronze has cooled down in the evening or the next morning, you may choose to lightly rub over the bronze with a dry soft cloth to bring out its luster.
If you have let too much time pass between maintenance sessions you may have developed issues with the patina. The best thing to do is to carefully clean what you can and then just continue on with a regular maintenance schedule.
Here is a short list of common problems and the most effective solutions to resolve them:
Loss of lacquer seal:
Reseal with clear paste wax. With brown patinas, you may also use Kiwi brown wax/shoe polish to revive (not repair) the patina so that it looks nice again. If it is a light patina and you have lost the original patina color, you may decide to use a Scotch-Brite medium maroon pad to bring out the bronze luster then reseal with paste wax. Again, this will revive the piece with a new patina but it will not get it back to the original.
Calcium buildup from exposure to water:
The first thing to try is just firmly wiping the calcium off with a damp rag. This is effective if there is not much buildup. If the calcium has been on too long then it will actually penetrate the lacquer and adhere straight to the bronze. You may try to remove the calcium with a medium Scotch-Brite then reseal with clear wax for light patinas and Kiwi brown shoe polish for dark patinas. Again, this method does not get the bronze back to the original color but may aid in reviving your patina.
Chemicals going a weird color:
In this case, you may live with the new color or have the patina redone. That is why I avoid these notoriously unstable chemicals.
The patina has gone dark:
Some of that is the natural aging of the bronze and can be embraced with its age. Just like people go gray, bronzes go darker over time. If you don’t want this to happen then you need to plan your budget to have the patina sandblasted and redone periodically over the years. Applying brown Kiwi wax/shoe polish can really help to liven up a dark patina, but it will still be dark.
The patina has gone green:
This is what copper does and a lack of maintenance will eventually make any outdoor bronze go green. Again, you may embrace it by putting a coat of paste wax over the surface to bring out the new patina’s luster and coloration. Your other options are to have the patina redone.
Whitish green spots have developed on the patina:
This is due to internal leaching of copper oxide to the surface of the bronze through the porosity of the metal. In this case, you may use a rag to dip into some lacquer thinner. Remove the lacquer seal in just that spot. Rub with that same rag on the spot that has the leaching to remove as much of it as possible without removing the original patina. If the original patina begins to come off and you are beginning to expose bare bronze then stop immediately. You may decide to ask a professional if it needs to be touched up at that point. If you are being careful then you can just add a clear wax and the spot should, for the most part, disappear.
The white colors on my patina have yellowed:
Again there is the choice to embrace the new patina with a paste wax application or a professional patina artist may apply a new coat of titanium oxide over the existing patina and blend it into the old. If you want to do this, don’t apply paste wax on the patina until the new adjustment is made. Then get back on a maintenance schedule.
The bare bronze is exposed through the patina:
This is simply because the patina is getting rubbed off from people rubbing the bronze too much. Bronze is tactile and should be touched, but constant rubbing will eventually work its way through the lacquer seal and expose a polished bare bronze. This isn’t always bad. Sometimes a patina artist will purposely create this effect to create an antiqued look. If you don’t like this look then limit the number and type of hands and feet that touch your bronzes.
Scratches on the Bronze:
The best thing to do is call a professional and describe the nature of the scratches to see if there is a quick fix or if more aggressive methods are needed for repairs.
- Do not use solvents like Lysol or Pledge to clean your Bronze. Do not use Brasso or CLR. These things can remove the seal and make your bronze even more vulnerable to unwanted color change.
- Do not use steel wool, stiff brushes or abrasive pads unless your intention is to remove the patina and expose the bare bronze.
- Do not get mad at a sculptor or patina artist if you are NOT following the proper maintenance schedule of instructions. Or, if your placement of your bronze is just asking for trouble, like in a water-fountain, near to the ocean, near a pool, near your kitchen sink, or where your dog likes to mark its territory.
I know this is a lot of information, but most of these processes are pretty straightforward. My goal is to give you the knowledge to empower you to be an expert on bronze ownership. To me, bronze is the art form that transcends time, should be enjoyed for generations, and should not be feared due to a lack of knowledge. Bronze is beautiful even when it begins to take on age. I believe that any true art collector should get into bronzes for their own delight and that of their posterity.
Please feel free to email me (firstname.lastname@example.org) any questions you may have from these guidelines. I am always happy to help if I can. If I don’t know an answer, then I know people who do.