Powder coating has become increasingly popular as a durable and environmentally friendly alternative to traditional liquid paint. In our line of business, powder-coating is a necessity – it is one of the best ways to offer customisation, which is important to clients for various reasons ranging from branding to adhering to a certain aesthetic. This is why, in 2015, we invested in an in-house powder-coating facility. It allowed us to enhance the quality control of our products and reduce our lead times, providing our customers with efficient and reliable service because we knew how important all of those things were to our clients.
Powder coating offers a versatile and efficient finishing solution, but what exactly is powder coating, and how does it work? In this guide, we’ll explore the ins and outs of powder coating, including its process, benefits, and applications.
What is Powder Coating?
Powder coating is a way of applying colour to metal. It is a dry finishing process in which fine particles of pigment and resin are electrostatically charged and sprayed onto a surface. Unlike traditional liquid paint, powder coating doesn’t require a solvent to keep the binder and filler parts in a liquid suspension form. The charged particles adhere to the surface, creating a uniform and smooth coating that is very sturdy and looks very good.
The method is known for its high-quality finish and long-lasting results. However, powder-coating isn’t just for colour. It is also an excellent way to add another protective layer to your metal. This layer helps the metal resist any environmental damage that will naturally occur with prolonged use. By preventing water or salts from getting to the metal in the first place, the powder-coated paint makes it harder for corrosion to start affecting the metal.
How Does Powder Coating Work?
As we said above, the powder paint is sprayed onto a surface and because the particles are electrostatically charged, they stick to the metal, coating it in colour. However, there is a process that needs to be followed for best results and skipping steps may lead to a lack of uniformity in the colour and a rough finish. Here are the powder-coating key steps to ensure a durable and high-quality finish:
Preparation: The first step in powder coating is preparing the surface. This involves cleaning and pre-treating the material to remove dirt, oils, or existing coatings. Proper preparation is crucial for the powder to adhere correctly and to ensure a smooth finish. You can sandblast or chemically clean the metal piece to remove any current finish.
Application: After the surface is prepared, the powder coating is applied using an electrostatic spray gun. The gun imparts an electrostatic charge to the powder particles, causing them to be attracted to the grounded surface. This electrostatic attraction ensures an even and complete coating.
Curing: Once the powder is applied, the coated object is placed in a curing oven. The heat from the oven causes the powder to melt and flow, forming a continuous film over the surface. The typical curing temperature is around 200°C, and the time required depends on the type of powder and the thickness of the coating. After curing, the result is a hard, durable, and attractive finish.
Advantages of Powder Coating
The most obvious advantage of powder-coating is the ability to colour almost any metal part. In the past, the pallet choices weren’t very extensive, but nowadays, this is not a worry—the RAL colour system has over 2500 colour shades you can choose from. There are thousands of options on the market so that the metal can be easily painted in a specific client colour for branding or aesthetic purposes. This gives freedom and flexibility when it comes to design.
However, the biggest advantage of powder-coating and the reason so many clients love it is that it improves the metal’s durability and gives it a longer lifespan. Powder-coating makes the metal more resistant to corrosion, as it doesn’t let water or salts penetrate beyond the paint layer. Compared to liquid paint, it is also harder to scratch, chip, and fade. This isn’t to say it won’t scratch, but it gives you extra protection.
This makes powder-coating an easy route to buying cost-effective products. The extra protective layer reduces maintenance, re-coating needs, and the chance of rust developing. Even though there is an added cost initially, there are long-term savings to be considered.
Lastly, powder-coating is much more environmentally friendly due to its lower VOC emissions, which are usually higher for liquid paints. Powder-coating is solvent-free, meaning it releases negligible amounts of VOCs during application. There is also less waste as any overspray can be collected and reused, unlike liquid paint, which means there is less consumption of raw material. This results in a much cleaner and safer working environment.
Maintenance Tips for Powder-Coated Surfaces
Powder-coated surfaces are renowned for their durability and resistance to corrosion, chipping, and fading. However, like any finish, they require proper care to maintain their appearance and performance over time. Here are some practical tips to help you extend the life of your powder-coated surfaces:
Regular Cleaning
Regular cleaning is essential to prevent the buildup of dirt, grime, and pollutants that can damage the powder coating. There are a number of ways to clean powder-coated metal, but good old soap and water are a great starting point. Use a mild detergent and warm water to clean the surface, and rinse thoroughly with clean water. You can also use high-pressure washing, but keep the pressure below 1,450 psi and the water temperature below 140°F (60°C) to avoid damaging the coating.
Avoid using abrasive cleaners, brushes, or pads, as they can scratch the coating. And be careful with harsh chemicals – if you wouldn’t want them on your skin, you probably don’t want them on your powder-coating either. Another best practice tip is to remember that filtered water is best if possible since it won’t leave any stains. Unfiltered water can lead to staining due to the chemicals like chlorine, sulfur or fluoride that can often be found in it.
Avoid Harsh Chemicals
This deserves a separate mention since it is important: Remember that harsh chemicals, solvents, and strong acids or alkalis can damage the powder-coated finish. Avoid using products like paint thinners, acetone, or bleach. Instead, opt for pH-neutral cleaning solutions that are safe for powder-coated surfaces. If you start damaging your powder-coated products, they will begin fading, and the powder-coat will lose its protective qualities.
Waxing and Polishing
Not all products will need this, but some surfaces that are frequently touched or come into regular contact with other objects may benefit from occasional waxing or polishing. This can enhance their appearance and provide an additional layer of protection. Use a high-quality automotive wax or polish safe for powder coatings, and apply it according to the product instructions.
Protect from Physical Damage
Powder-coating adds a great protective layer to metal, and it helps maintain it scratch-free, but it is always a good idea to take extra care to prevent physical damage to the powder coating by avoiding impact, abrasion, and excessive friction. Be mindful when moving objects near powder-coated surfaces, and use protective pads or covers when necessary. If the paint gets a deep scratch, this might expose the metal underneath, becoming an entryway for moisture, which can lead to corrosion. In such cases, you can use touch-up paint to cover the damaged area.
Inspect Regularly
Once you have installed your product, you should regularly inspect your powder-coated surfaces for any signs of damage, such as scratches, chips, or peeling. Early detection of issues can prevent further damage and allow for timely repairs.
Reapply Protective Coatings
After long years of service, there might come a time when applying a clear protective coating over the powder-coated surface can help extend its life and enhance its resistance to UV rays, moisture, and chemicals.
Powder coating is a highly effective and environmentally friendly method for applying a durable, attractive finish to metal surfaces. It offers superior protection against corrosion, scratches, and fading while providing various colour options for customisation. Proper maintenance, including regular cleaning and inspection, is essential to preserve the longevity and appearance of powder-coated surfaces. If you have any questions about our products and the colour options we offer, don’t hesitate to contact us.