One of the advantages of powder coating is that it provides an excellent aesthetic as well as practical finish to different, mainly metal, substrates.
Obviously, the end result of a powder coating application will depend on the quality of the original surface, but it can cover up minor imperfections such as scratches.
How effective powder coating is in covering up scratches also depends on the type of powder coating you choose.
Couldn’t I Just Paint Over Scratches?
You might think if you have scratches on a metal surface, then simply touching them up with a bit of paint will do the trick.
The likelihood is that this won’t look nearly as good a freshly coated item.
You could, therefore, choose to re-spray the whole thing with liquid paint. But first consider the advantages powder coating has.
Powder coating is a strong, attractive and long-lasting alternative to liquid paint.
Here are some of its benefits:
- Powder coating is durable, which will last longer than a typical liquid paint finish
- It is fast, enabling good, lasting finishes in a single coat
- You get a broad choice of colours and shades, with availability in RAL and other colour matching systems
- It provides a consistent, even coated finish, with no trace of application marks
- Powder coating is eco-friendly, because it does not contain volatile economic compounds (VOCs).
What Is Powder Coating Made Of?
Powder coatings come in different varieties. Two of the most commonly used are polyester and epoxy.
Polyester is a thermoplastic powder coating, while epoxy is a thermoset powder coating.
Both are durable. Thermoplastic polyester coatings are multi-purpose and provide a good degree of protection against wear and tear.
You will find polyester powder coatings on outdoor surfaces, including some car parts and on exterior building features.
Thermoset epoxy powder coatings are more heat-resistant, and generally provide a harder finish than thermoplastic coatings.
Epoxy coatings are effective in electrical insulation, hard-wearing in outdoor conditions, but can eventually start to crack if exposed to UV light for prolonged periods.
What Sort of Finish Does Powder Coating Provide?
With powder coating, you can expect a high quality finish. Applying the electrostatically-charged powder provides an even and comprehensive surface coverage.
Then the baking process, where you heat the applied powder, causes it to run and fuse together, forming a tough but even outer shell.
If the surface you’re coating has scratches, then this will fill them and cover them.
Is Powder Coating Scratch Resistant?
There are different types of powder coating, and some are more effective than others when it comes to scratch resistance.
Research into the relative scratch resistant properties of powder coatings indicates that you can enhance these properties with the addition of molybdenum disulfide (MoS2).
This is a form of solid lubricant.
Testing the addition of MoS2 on both polyester and epoxy powder coatings when applying them to an aluminium substrate shows a reduction in the friction coefficient and higher resistance to wear.
Adding MoS2 to either polyester or epoxy powder coating can bring about a significant increase in their scratch resistance.
Example: Architectural Features
Polyester powder coating of aluminium and steel substrates is an established finish for external architectural features such as windows and doors.
Modern, durable powder coating finishes provide extended lifespans for these features, protecting the metal substrates underneath.
Another aspect of architectural powder coating is that it retains its colour over prolonged outdoor exposure.
It is applied to:
- Window frames
- Doors and door frames
- Canopies
- Fixtures and fittings
- Railings
- Fascias
- Gutters
- Outdoor seating.
Can You Repair Scratched Powder Coating?
Even with a powder coating designed for durability, it can suffer from wear and tear over time.
Where there are light scratches and blemishes, you can repair scratched powder coating by applying colour-matched liquid paint to it carefully.
For more pronounced defects, you may be able to sand and buff them down.
However, as a durable and fast method for providing a strong but attractive finish, you should also consider applying a fresh powder coating where there has been damage.
With a rapid application and curing time, this will often be the most effective way of dealing with scratches, and creating surfaces which are tough but attractive, for long-term use.
We’re powder coating experts and proud of the service we provide. For more information, or a quote, please contact us.
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