Finishing is one of the essential processes in the blacksmithing profession because it provides the final outlook to your projects. Aside from adding a touch of class and neatness to your work, some finishes also protect your work. Creative finishing can make your metal work more valuable. So, it is a great idea to learn how to patina steel.
Are you familiar with patina finishes, or is this your first contact? Here is an opportunity to know and learn more about patinas for steel and metal. What is patina finish?
Patina finishing is one of the most classic finishes in the blacksmithing profession. Patina is usually created from a chemical reaction and acts as a coating on bare metals’ surfaces. The patina’s nature is unique compared to the conventional use of powder coatings and paintings.
Do you wish to know how to patina steel or how to patina metal? You are on the right page. In this guide, you will learn about steel patinas and how to patina stainless steel.
The creation of beautiful patinas on steel can vary with the type of patina that is to be created. There are four major types of beautiful steel patinas, and they are;
Rust Patina
Rust patina is just like its name. It is the coating of rust oxidation on your steel. Rust patina can happen naturally when you expose bare steel outside in the weather.
After days or weeks of this exposure, oxidation will start on the surface of the steel. The rate at which the coating will happen is dependent on the weather. The most influential factors are moisture and humidity.
The natural way of oxidation might take time. The use of chemicals will accelerate this process and make it more appealing.
Most chemicals for this process are readily available for sale. If you want to create a rust patina on your steel, there are certain steps you must follow. Likewise, you must have the right tools and chemicals.
Rust patina is made from ingredients that are cheap and readily available. The major elements in rust patina are;
- Rust bluing with hydrogen peroxide
- Vinegar, chlorine bleach
- Salt and muriatic acids
- As well as natural factors like air, sun, and water.
The primary aim of rust patina is to prevent rust oxidation on materials like steel. After appropriately mixing the ingredients, you have to repeatedly apply the mixture to the metal for a few days.
Steps to Create Rust Patina
These steps will put you through how to patina steel with vinegar and other chemicals.
STEP 1: Get your tools and materials.
It would be best if to get your tools and materials ready before you start the coating process. The chemicals are as stated above, and they are available for sale.
The tools you need for the process include;
- Measuring cup
- Measuring spoons
- Spray bottle
STEP 2: Degrease the metal and prepare the surface.
This process is to ensures proper penetration of the chemical to the surface.
Ensure you remove coating, painting, or any other initial finish on the surface of the steel. You can then use a degreaser to prepare the surface. Don’t forget to wear gloves and goggles as you are dealing with harsh chemicals.
STEP 3: Pickle the metal.
The essence of pickling the metal is to have a uniform coating on the surface. All you need to do is put some vinegar in the spray bottle and let it cover the steel’s surface.
STEP 4: Rust the metal by adding the rust aiding process.
The chemicals you need for this process are salt, hydrogen peroxide, and salt.
STEP 5: Finish up and perfect your work.
Ensure that the surface now has a consistent finish but be careful not to touch.
Note that only clean, bare, and degreased steel will rust uniformly. Else, the pattern on the steel might be inconsistent and undesirable.
Pros
- It protects the steel
- Give your steel surface an appealing appearance
Cons
- It uses some chemicals that are corrosive and toxic
Pro Tip: Poorly prepared steel might not work. Only degreased, clean, and bare steel will give you a perfect result.
Heat Patina
Heat patina involves creating an impressive pallet of color on metal. The oxygen from the air is released after interference with heat. The oxygen then forms oxide with the air. It is sometimes referred to as heat coloring on steel.
The heat patina is formed by heating the metal in the atmosphere, thereby producing beautiful colors. These colors are formed when oxygen reacts with hot steel, which results in oxides formation.
Process of Heat Patina Formation
Heat patina on steel requires lesser ingredients in comparison to rust patina. The necessary factors are just air and heat.
The oxides first produce thin layers before yielding transparent colors after experiencing the interference effect. However, the only limitation with this type of patina is that the shades can quickly go out of control.
Therefore, you might need to keep a constant eye on your metal all through the process. You might also need to regulate the heat or interference to keep the operation under control.
Ensure that you are using a consistent heat source if you want to get appropriate results. Although you can use a torch as your heat source, it won’t give you the best result. Torch does not produce an even heat.
Consider the option of more consistent heat sources like an oven or ceramic support over an electric heat source.
You can go creative with this process to give a more interesting pattern. Place a few drops of oil or water on the metal’s surface if you intend to create more interesting patterns.
Note that you might have to protect the surface with periodic application of renaissance wax. This wax can also help to protect more delicate coatings.
Pros
- It is safer and easier to make
- It is flexible and allows you to create diverse, interesting patterns
- Heat patina is less expensive and uses limited chemicals
- The finish is classy and beautiful
Cons
- The colors are difficult to control
- You need to be careful of heat sources and hit metals to avoid burns
Pro Tip: Polished or bare steel works best for this process. It will give you vivid and coordinated color patterns.
Black Patina
The black metal patina finish is another impressive type of finish. This patina type does not have a long list or exclusive ingredients unlike rust patina. All you need are regular blackeners, as well as gun bluing.
Gun bluing is readily available in most sports stores. It is majorly used for gun barrels, producing their beautiful bluish-black coloration.
The application is as simple as the ingredients; apply the mixture to the face of stainless steel. Once you achieve your desired result, you can rinse the mixture.
Black metal patinas are a common pattern on gun barrel finish. It gives a superb bluish-black finish on gun barrels.
Safety should come first while embarking on this project. Be careful while handling gun bluing. This light blue substance is quite toxic and potentially dangerous.
The blue gluing substance is quite acidic, and it will turn mild steel to black if they come in contact. This effect is almost immediate.
You have little or no control over the pattern formation. Ensure that you apply the gun bluing agent in the right proportion at the right time.
The major reason for the corrosive and fast action of this element is the presence of selenium dioxide. Selenium dioxide is responsible for oxidizing iron.
The result of this oxidation is magnetic black iron oxide. It also leaves a notable deposit of elemental selenium.
Do you want to know how to patina steel black? Here you go!
How To Make Black Patina Finish
Like every other finish, preparing the surface of the steel is crucial to this process. Only apply the finishing agent to clean steel.
Leave it to burn till you have your desired result, and rinse quickly. Ensure that you thoroughly rinse off this patina finish. If you fail to rinse it thoroughly, it will cause the metal to start rusting under the finish.
Do not apply gun bluing on stainless steel alloy because it won’t be effective. It will only result in a mere waste of resources.
Pros
- The black patina finish is easy to make
- It gives superb patterns
- It only requires gun bluing and blackeners
Cons
- The black patina finish is ineffective on stainless steel alloy
- Gun bluing and other common blackeners contain copper salts and other potentially dangerous oxidants.
Pro Tip: Use clean and shiny metal for this process. It will give you the best result.
Copper Patina
The ingredients for this patina type are the origin of its name. The copper patina uses a solution of copper chloride, and slightly acidified copper sulfate.
Copper patina works best on bare steel. Hence it requires diligent surface preparation and care to get the best possible finish.
Do not mistake copper patina for electroplating. Besides the fact that it is not as durable as electroplating, the process is more like immersion plating.
Iron is more chemically active than copper. So, it won’t work if your copper compound is dissolved in water. Some of it will be displaced by the more active metals like iron present in the steel.
It is essential to add a little acid to your copper solution. This addition activates the steel by eliminating residual oxides. It will also help to gather and discard the salt gathered in this process.
How to Apply Copper Patina
You can apply it to bared steel. Apply the mixture on the bare steel’s surface and use clean water to rinse it off. Once the combination is entirely off the steel’s surface, you can proceed to seal it in a clear coat almost immediately to prevent the steel from rusting underneath.
It is best to start with a few drops of muriatic acid or sulfuric acid and a 10% copper sulfate solution. This proportion will give your desired result. You can also go for proprietary products offered and tested extensively.
Pros
- It is easy and less expensive to make
- It gives a superb pattern
- The process is easy to control
Cons
- Copper salts, which are one of the main ingredients for the process, are toxic to the environment.
- The adhesion can be tricky.
Pro Tip: Degrease and properly clean bare steel before immersion
Frequently Asked Questions on How To Patina Steel
Is Patina Good or Bad for Your Steel?
The good or bad status of patina steel is one of the common curiosities among many blacksmiths. Many are aware that patina is also a form of corrosion. The common myth is that all corrosions are destructive.
This is not true! The patina on metal or steel patina finishes is not a destructive form of corrosion. It is a controlled type of corrosion that aims to protect your steel and define color patterns.
So, it is safe to say patina fishes are good for your steel. Another interesting good part of this finish is that it will help you protect against red rust.
Patina raises the value of your copper and copper products. It will also keep it intact for a longer time without compromising its value.
Steel patina is a good way to go for your finishes. Choose the most suitable types of patina for various processes.
Is Patina the Same Is Rust?
Patina is entirely different from rust. Although they appear similar physically, they have different actions on the steel.
The actual rust is destructive and will damage your metal, while the patina does the opposite. Patina finishes will protect your metal from actual rust, increase its value, and give vivid coloration.
The word “rust” appears in the description of patina finishes because of the lack of a better word for description. They have similar orange colorations but different chemical and value implications.
Conclusion
Coating performs a lot of functions, including protection and beautification. Creating patina finishes for your steel is not difficult as long as you have the right ingredients.
The major determinant of the patina to create is the pros and cons of the patina type and the preference of the blacksmith.