Finish Types and Benefits

Each finish adds style to your unit and a layer of protection. Learn how various finishes are applied and how they protect with the MCDLG Newsstand.

Designing exteriors for a building? You’re going to need louvers that fit the aesthetic. Looking for a way to differentiate between dampers in your ductwork? Consider ordering dampers of assorted colors to help technicians spot the difference. There are several ways to add color to louvers and dampers. Each finish type has benefits and limitations.

Interested in louver design? Airline Louvers can help! Contact Airline today and let's work together on your next project.

Powder Paints

Powder paints are the most common in the HVAC industry because of their longevity. Painters apply a dry powder to the product, then cure the coating with heat. Powder paints can be mixed with a cross-linker, typically polyester or epoxy resins, which help polymerize the paint during the baking process. This mixture creates a more resilient coating that resists marring and chalking. For this reason, powder paints are the most popular finish type.

Before application, the product must be thoroughly cleaned. After assembly, louvers will often have oil, grease, and other impurities on their surface. Manufacturers can use a variety of methods to clean the louver, such as power washing or a chemical bath. The louver must be clean to ensure the best possible bond between paint and metal.

Powder paints are applied with an electrostatic gun via a process called Electrostatic Spray-assisted Vapor Deposition, or ESAVD. The paint gun imparts a negative electrostatic charge to the powder. The unit receiving the coat will be grounded in the painting chamber, so that it attracts the statically charged powder. In other words, the powder paint is drawn to the louver as it leaves the spray gun. The attraction between the powder and the metal ensures maximum coverage across the unit and minimizes wasted paint.

Once the powder paint is applied, the unit is taken to an oven to bake and cure the newly applied coating. The powder will melt at around three hundred degrees Fahrenheit and disperse across the surface of the product. This baking stage also creates a uniform coat across all sides of the product. The heat is increased to around four hundred degrees Fahrenheit to begin the curing process, which takes 10 to 15 minutes to fully cure. The resulting coat will have a long-lasting bond with the metal.

Powder paints cure faster than liquid-based paints and produce a thicker coating, which makes them more resistant to marking. This finish type keeps its color longer than standard wet paints. Powder paint finishes rarely require touch-ups over the life of the unit. This makes powder paint the go-to option for louvers because of its resilience and longevity.

Manufacturers typically offer a wide range of colors with their powder paint finishes. For instance, MCDLG offers thirty-five base colors to choose from, including shades with a metallic shine. Your color options don't end here. Powder paints are also an excellent option for projects that need a specific color to match the building's aesthetic. MCDLG offer color matching services. Provide a sample color and we can match the unit's finish to your sample. Make your louvers blend with the surrounding features or make a nice contrast. Color matching can help bring architectural designs to life.

Do you need louvers with custom finishes? MCDLG can help! Request a color chart today and browse our finish options. We make sure your louvers fit your project's aesthetic.

Fluoropolymers

Fluoropolymer finishes are powder paints consisting of high-performance resins and fluoropolymer lubricants. These components create a smooth and solid coating. Like all powder paints, fluoropolymer finishes are applied through EVASD, but they can also be applied with the conventional compressed air spray. The application method will depend on the type of fluoropolymer used in the process. When applied via EVASD, the mixture will be applied to the product, baked, and then cured in an industrial oven. The resulting finish is long-lasting, highly resilient, and smooth to the touch.

The smoothness of a fluoropolymer finish can reduce friction between moving parts. This makes it a good option for adjustable louvers. Fluoropolymer finishes are also resistant to corrosive chemicals, heat, and abrasive materials. This is good for louvers installed in areas that deal with caustic materials. You may also have the option to add a clear coat to further increase the durability of the finish.

Anodizing

Anodizing is a popular finish option for louvers and dampers made from aluminum. Anodizing is an electrochemical process that converts the surface of a metal into a durable and corrosion-resistant anodic oxide. It doesn’t just apply a resilient coating to the metal, like powder paints. It integrates with the metal.

The product is connected to an electrical current and dipped into an acid electrolyte bath. A cathode is introduced to the bath to begin the process. The electrolytes release oxygen ions which are attracted to the anode, which is the product submerged in the bath. These oxygen ions bond with the atoms of the metal along the surface of the product. In a sense, anodizing is a form of controlled oxidation. By anodizing the metal, you create a protective barrier against natural corrosion.

Aluminum is the best choice for this process because the oxide build up can easily fill in the micropores along its surface. Read this article for more on extruded aluminum and other metals commonly used in louvers and dampers. Anodizing works best with aluminum, but it is possible to anodize other metals like galvanized steel. 

Standard anodizing will result in a dull, bare metal look that resembles a base mill finish. Anodizing does not change the color of the product. Manufacturers can add a dye during the anodizing process, such as bronze or black, to add color to the finish.

However, different metals for louvers will react in different ways during the anodizing process. The final color may differ depending on the type of metal and the composition of the alloy used to build the product. You can also add a clear coat to add a shine to the finish. 

Resins, Lacquers, and other Finish Options

Manufacturers may offer other options for finishes, such as epoxy phenolic resins, lacquering, etching, and base coats. Phenolic resins are highly resistant to chemicals and corrosion, which makes them an excellent finish for louvers and dampers that will be exposed to caustic vapors or other hazardous materials. Lacquers add a shine to the unit’s metal for a cheap price, but it won’t provide the same resistances or longevity of a powder paint.

Etching involves submersing the unit in an acidic solution for a brief period, which adds a unique burnished look to the metal. Etched units can also receive lacquer to add a dull shine to the surface. There are also options for base coats, for painting units in the field. Base coats can ensure a better bond between the metal and whatever paint you decide to use.

There are plenty of options available, but the best choice depends on the needs of the project. For louvers, you will want a resilient finish that lasts a long time.

For more on louvers and dampers, check out these Newsstand articles:

• Louver Aesthetics - Form, Shape, Color
• Blades with a Purpose - For Louvers and Dampers
• Combination Stationary - Two-in-One Louver Solutions

Need help right away? Contact MCDLG today. We are ready to help you.