Powder coating is a part of our daily lives. Many common objects we come across everyday are powder coated - from the furniture and railings in your house to car parts like wheels and rims. So have you ever wondered what the powder coating process is like?
We'll explain that in detail here.
Powder coating is a protective method for coating metal objects and components to make them more durable and attractive. Unlike wet paints, powder coating is a dry finishing process with a uniform coat that doesn't drip or run. Powder coating works best on metal surfaces such as steel and iron. However, its application has also extended to non-metallic objects, such as glass and wood in recent decades.
Powder coating is often the penultimate step in manufacturing to give objects the desired color, texture, or protection. Many industries use this method for finishing and refinishing their components. From automotive to architectural, furniture to industrial, powder coating has a wide array of applications in several industries. The durable and attractive finish of powder coating is what makes it the preferred choice for metal finishing.
How Does Powder Coating Work?
The obvious question that springs to mind is, what makes powder coating better than liquid paint for finishing? And what makes the coated products so durable? Let's answer them first.
Powder coating is an electrostatic process that utilizes dry powder deposited onto objects' surfaces through an electric charge. The powder is made of pigments, resins, and curatives, which are melted together and then ground into powder.
What makes them the preferred finishing choice is that powder coating has several colors and textures options, ranging from gloss and metallic to even fluorescent. Paint shops also offer custom coating services tailor-made to the component you want to be coated. Apart from its ability to provide a uniform finish with multiple choices and an attractive appearance, powder coating also protects ferrous objects from corrosion.
Powder coating works by the deposition of powder through a process called electrostatic spray deposition. The powder carries an electrostatic charge, which makes it adhere to the grounded metal object. The powder sticks onto the surface and is cured for a uniform finish. This is the most common way to apply powder.
Another method for powder coating is the fluidized bed system. In this method, the parts to be coated are heated and dipped into the powder, which melts over the surface.
The Powder Coating Process
As mentioned above, the powder coating process entails the deposition of charged powder on object surfaces.
You need special equipment for powder coating, the chief elements being an electrostatic gun for the charge, an oven to heat the powder, and protective gear like a face shield, gloves, and a respiratory for the personnel involved.
The first step in any refinishing process is the pretreatment part. And powder coating is no exception. Pretreatment is a surface preparation method before the actual coating job for removing dirt, grease, oil, or other contaminants and cleaning the surface. This part is essential to achieve proper adhesion of the powder and increase the overall durability and performance of the coat.
In a typical setup, the powder is released from a gun, which emits it in a diffused form. A low amperage power unit provides the electrical charge to the powder as it moves through compressed air inside the gun and gets attracted to the substrate.
The next step is the curing process, in which the object is baked or heated in an oven at 400 F (approx) for 25-30 minutes. Curing ensures proper adhesion of the powder with a protective layer over the substrate. The temperature and time for curing vary as per the size and nature of the substrate.
Here's a step-by-step guide to the powder coating process:
Step 1. Preparation
The surface is prepared with mechanical processes like abrasive media blasting and with chemical compounds to remove contaminants and ensure proper powder adhesion.
Step 2. Selection
Your powder coating applicator will present you with choices for colors and textures of powder coating. You can select the color, texture, and finish of your choice.
Step 3. Application
The powder is sprayed using the spray gun. Moving through compressed air inside the gun, the powder gains an electric charge upon leaving the gun and sticks to the surface. The applicator will continue spraying until the entire part is covered.
Step 4. Curing
The object is then heated inside curing ovens at temperatures ranging from 350-400° F. The heat melts the powder to form a consistent protective layer on the surface. This process can take anywhere up to 30 minutes, depending on the object to be coated and its size.
Step 5. Delivery
Once the parts are properly coated and subsequently cooled off, they're ready for package and delivery.
Why Choose Powder Coating Over Liquid Paint?
Powder coating is a highly efficient finishing process with several benefits over liquid paint. Here are some reasons why:
Most powder coating projects require a single coat, thus minimizing the project cost. The disposal costs of powder coating are also lower than wet paint.
Powder coating scores one over wet paint due to its ability to adapt thickness to the coated object. You can achieve a thick coating without any effect on the aesthetics.
● Aesthetic Appeal
Powder coating also adds a decorative element when needed. You have a wide array of color, texture, and finish choices to create the desired final appearance.
● Compliant and Environmentally-friendly
Powder coating is an eco-friendly alternative to most other finishing methods, including solvent-based paint, as they don't contain any chemical solvents and release minimal to zero volatile organic compounds (VOC)into the atmosphere.
Rusty Lions Can Fulfill All Your Powder Coating Needs
Rusty Lions has the experience, expertise, and equipment to powder coat all metal and non-metal components to your custom specifications. We know powder coating with seasoned professionals who have served many automotive, architecture, and industrial clients in New Jersey for many years.
We also offer sandblasting, restoration, cerakote, and other metal refinishing services. Get in touch and discuss your powder coating project with us.