Powder coating and wet painting are two of the most popular finishes — specifically for metal products. Though they share some similarities, they differ in terms of color mixing, durability and cost.
A finish is necessary to prevent corrosion. Without one, certain metals like iron will react with oxygen and rust. Thanks to processes like powder coating and wet painting, you can avoid rust and erosion.
You may be wondering which of the two is objectively better. However, they each come with their pros and cons — here’s a closer look at each method.
Composition
You’ll find various similarities and differences when studying the composition of both materials. Both contain resins — a type of paste or malleable substance that can harden under the right pressure, heat and circumstances. The resins in powder are usually polyester, polyester-epoxy, acrylic or polyethylene.
Both powder and paint also contain different pigments for coloring and additives for preservation and performance.
The main difference in composition is that wet paint contains solvents, whereas powder does not. Since the paint is a liquid, the solvent is necessary to maintain the right fluid consistency. The powder doesn’t need a solvent because once the crushed pigments and plastics become powder, they maintain that color and consistency.
Application
The application process for both materials is relatively similar. Both require the use of a pressurized gun, also known as an electrostatic gun, to spray the powder or paint onto the object’s surface.
Before that, though, experts must prepare the item with deep cleaning. Some sanitary solutions will work — other times, finishing professionals use sandblasting to remove debris like rust and dirt from the object. This intense process works well for removing imperfections.
Then, the electrostatic gun applies the material in a full, even coating. One difference here is that professional painters may be needed to apply the wet paint, so there’s no unevenness. With powder coating, though, most skilled workers can apply it.
The gun provides positive and negative charges for the powder, which the metal surface then attracts. Afterward, the powder-coated item cures in an oven where the heat gels the powder. Thermal bonds then form between the powder particles. Similarly, painted objects may cure in an oven or air dry.
Color and Texture
In terms of color and texture, the two materials continue to differ.
Since paint is so abundant and popular, it’s much easier to find various colors. Additionally, most paint stores offer the option to mix and match. You can bring a swatch or idea in, and the employees can usually provide you with exactly what you’re looking for.
Powder, however, mostly has a set color availability. If you want to have specific mixes, you have to special request them, which can be time consuming. When designs require precise colors, like public exteriors, paint may be the best option.
Similarly, texture varies based on the material. The more coats you add of both, the more their texture will vary. For instance, a wet paint booth can offer finer precision coverage. Similarly, a thicker layering of powder will be smoother. A thin layer of powder will feel more natural. However, if you want a high-gloss look, go with liquid paint.
Durability
Depending on the job specifications and requirements, some experts will want to focus on guaranteeing durability and ensuring the object has a long lifespan.
In this area, powder coating takes the cake. Though wet paint provides a sleek texture and elegant finish — which is nice for modern designs — powder coating will last longer and protect against damages.
Due to the thermal bonding in the application phase for powder, the curing protects the coating from chips, scratches and wear and tear. This finish will hold up against external factors, so it will still look natural and professional throughout the years. A wooden door, for instance, may require a natural look.
Additionally, since powder can come in thick layers, the buildup protects against heat, sunlight and moisture. Therefore, chalking — which causes a breakdown of paint resins and adhesion — won’t harm the product.
Cost
Regarding pricing, paint and powder each have their benefits and considerations.
Paint is cheaper, which automatically makes it a bigger seller. People want more inexpensive products that will still look nice. Paint does just that. However, since it can wear down over time, repainting becomes necessary. This corrosion means more paint purchases are also a requirement.
Large-scale projects like housing initiatives or public buildings will likely benefit the most from paint. Since contractors will need more materials, they will likely look for something less pricey.
On the other hand, powder is more expensive, but it lasts longer. Overspraying paint can lead to a huge loss of material. Finishing professionals are less likely to waste powder, however. It’s better for smaller-scale projects like metal beams or fixtures.
Safety
When it comes to safety, basic precautions are a must for both finishing methods. Protective equipment like eyewear, gloves and masks are necessary. Liquid paint may be a bit more dangerous to handle. This is because it can be flammable, which, in an industrial setting, could lead to chemical fires.
Additionally, paints usually have volatile organic compounds (VOCs), which can be harmful to air quality and human health. Coating powders, too, can come with health risks — it’s important to follow all precautions outlined by your workplace regulations.
The Finishing Touches
Which is better — powder coating or wet paint? The answer depends on the application. Both come with certain advantages, like powder being better for durability or paint being better for lower costs. Ultimately, both are effective for different reasons. It’s in how experts use them that their true benefits shine through.