Single stage vs base coat clear coat is a forever, on-going discussion amongst automotive painters. You have many that swear by single stage, while others say clear coats are the best. So, who is right and what does this really mean?
When it comes down to it, if you are on the fence trying to figure which type of paint to go with. Let’s look at two of the main concerns, to help you make a decision on which one to go with.
The two main concerns are, the look and durability of single stage vs base coat clear coat. Many think a clear coat gives a better protection against chips and the elements. Also, including you get a better look.
While others claim that a single stage paint gives a much deeper robust appearance. So, who is right, which is the better of the two? Let’s look first at the technical explanation of single stage vs base coat clear coat…
Single Stage Paint
A single stage paint is pretty much how it sounds. You will find automotive single stage paint a type in use in vehicle finishes. It combines the color and protective elements to eliminate the need for a clear coat.
Key Characteristics of Single Stage Paint:
Combined Coats: Single stage paint includes both the pigment (color) and a durable resin (usually urethane or enamel) that provides a glossy finish and protection, eliminating the need for a separate clear coat.
Application: The paint is applied directly to the vehicle’s surface after proper priming and preparation. It typically requires fewer coats than a two-stage system, which can save time during the painting process.
Ease of Use: Because it’s a single application process, it is often simpler and quicker to apply, making it a popular choice for DIY enthusiasts and for use in scenarios where speed and simplicity are important.
Durability: Modern single stage paints are quite durable and resistant to UV rays and chemicals, though historically, they have not always been as durable as two-stage systems. Advances in paint technology have improved the longevity and durability of single stage paints.
Appearance: Single stage paints can achieve a high-gloss finish similar to that of a clear-coated system. However, achieving the same level of depth and shine as a two-stage system might require more careful application and polishing.
Applications:
Restoration Projects: Often used in classic car restorations to replicate the original paint processes.
Economical Repairs: Useful in scenarios where cost and speed are critical, such as in some body shops and for personal vehicle touch-ups.
Fleet Vehicles: Frequently used for painting commercial and fleet vehicles where a robust and efficient painting process is needed.
Pros and Cons:
Pros:
- Quicker application process
- Often more cost-effective due to fewer materials and steps
- Simpler for DIY projects
Cons:
- May not offer the same depth of shine and longevity as two-stage paints
- Can be more challenging to repair if damaged
- Limited ability to achieve effects like metallic or pearlescent finishes compared to multi-stage systems
Overall Benefits:
Overall, automotive single stage paint is a versatile and efficient option for various vehicle painting needs, balancing ease of use with good durability and appearance.
Base Coat Clear Coat
Automotive base coat/clear coat paint is a two-stage painting system used in vehicle finishing, which involves applying two distinct layers: a base coat that provides color and a clear coat that offers protection and shine.
Key Characteristics of Base Coat/Clear Coat Paint:
Base Coat: This is the first layer applied and is primarily responsible for the vehicle’s color and aesthetic effects. The base coat can include solid colors, metallic, or pearlescent finishes. It doesn’t have the high gloss or protective qualities on its own and requires a clear coat to be applied over it.
Clear Coat: The second layer, the clear coat, is a transparent, protective layer that provides gloss and shields the base coat from environmental damage, such as UV rays, chemicals, and physical wear. It enhances the depth and shine of the color while offering durability.
Application Process:
Preparation: The vehicle’s surface is prepared by cleaning, sanding, and priming to ensure proper adhesion.
Base Coat Application: The base coat is applied in multiple thin layers to achieve the desired color and effect. It is allowed to dry before the clear coat is applied.
Clear Coat Application: The clear coat is applied in several layers over the base coat to build up thickness for protection and shine.
Appearance: This system allows for a deep, glossy finish with a rich color. The clear coat can be polished to enhance the shine further and remove imperfections.
Durability: The clear coat provides a tough, protective layer that enhances the longevity of the paint job. It resists UV radiation, chemicals, and physical abrasion better than single stage paint.
Applications:
OEM Finishes: Standard in modern automotive manufacturing, providing a high-quality, durable finish.
Custom Paint Jobs: Preferred for custom and high-end paint jobs where a superior finish is required.
Repairs and Refinishing: Commonly used in professional body shops for vehicle repairs and refinishing to match OEM standards.
Pros and Cons:
Pros:
- Enhanced Durability: The clear coat protects against UV rays, chemicals, and scratches.
- Superior Appearance: Offers a deep, glossy finish with vibrant colors and special effects.
- Repairability: Easier to repair and blend with the original finish in case of damage.
Cons:
- Complexity: More steps and materials are involved, making the process more complex than single stage paint.
- Cost: Generally more expensive due to additional materials and labor.
- Time-Consuming: Requires more time for application and curing between coats.
Overall Benefits:
The base coat/clear coat system is renowned for providing a high-quality, durable, and visually appealing finish. It’s the standard for modern automotive paint jobs.
It offers protection and an enhanced aesthetics that can be tailored with various effects and colors. While it requires more effort and expense than single stage paint.
The results typically justify the investment, especially for high-end and custom vehicles.
Busting the Myth About Durability of Clear Coat
They’re many people that think, a clear coat resist getting chips from road debris. The belief is that the clear protects the paint underneath it. I can tell you, that is far from true.
Understand, the two layers will bond, when a base coat clear coat paint job is being done correctly. Meaning, the clear is part of the base coat color. So, if the car gets a rock chip, it will take the paint off down to the primer or metal.
There is no more durability between base coat clear coat or single stage. So in the end, they are both top coats that can endure damage equally.
There are different types of clears and paints that also factor in with durability. You have synthetic enamel, acrylic enamel and urethane’s.
I can say this about base coat clear coats. If you get a chip and it only knocked off the clear but left the base coat, be concerned.
This is a strong indication that the clear didn’t bond into the base coat. This is huge factor on why many cars get the peeling clear coat issue. You can read more on How To Fix Peeling Clear Coat.
Synthetic Enamel Paint
This is an inferior enamel paint that is like old tractor and barn paint. It takes forever to dry and the surface never actually hardens fully. They do make a hardener for synthetics but it doesn’t help much.
When you sand a synthetic paint, it chips away more than feathers away. This makes repairs or even repainting very difficult.
When it comes to automotive, you will find synthetic paints are in use at places like Maaco. Maaco is a cheap paint job body shop that offers low quality service. You often see where these type shops offer a complete paint job for a little as $349.00.
All I can say, do not waste your time or money at these type shops. Real paint cost way more than that for a reason.
The best use for synthetic enamel paints would be farm equipment. Something you want color but don’t care about longevity.
Acrylic Enamel Paint
Acrylic enamel paints use acrylic resins as their primary binder. These resins derive from acrylic acid and related compounds. They provide a strong, flexible, and durable film when the paint cures.
Acrylic enamels are far superior to synthetic enamels. However, they are inferior to a urethane enamel. You may be thinking what does this have to do with single stage vs base coat clear coat.
There is a point to knowing these different types of and it’s relation to how single stage vs base coat clear coat.
Hardeners are most often used in acrylic enamels. This speeds up the drying a curing time, as well as increases the durability. I have seen single stage acrylic enamel paint jobs last over 30 years without an issue.
The acrylic resin provides flexibility, helping to prevent cracking and chipping over time. It also has excellent resistance to ultraviolet light, which helps maintain the paint’s color and gloss for longer periods.
Urethane Paints
Even though we call it automotive urethane paint, it is still enamel. In fact, it is acrylic enamel, it however, it is converts to polyurethane.
Unlike the previous paint types from above, urethane paints use an activator. Whereas, synthetic and acrylic enamels use a hardener.
A hardener is more like an accelerator, with a few chemicals to increase the durability to some degree. An activator has some solvents for drying times, but mainly a catalyst that aids in converting.
Urethane paints fall under what is known as the 2K family. Meaning it takes two parts for the chemical reaction to take place. This is the same as an epoxy, you have to have parts A and B.
Acrylic enamel paints are considered 1K, meaning it is air dry. Yes, you can add a hardener in it to speed up dry and cure time. But it doesn’t require the catalyst to dry, unlike a urethane paint.
You can basically consider a urethane paint like an epoxy. Urethane paints adhere far superior to the other enamels. They cure much faster and become very durable compared to all other paints.
Are Hardeners and Activators the Same Thing?
While doing my research to write this article, I found many posts claiming they are the same. The people who wrote those articles, need to go back to auto body school. A hardener and activator are not the same.
In fact, knowing the difference in a hardener and activator, is kind of key in single stage vs base coat clear coat.
An activator and a hardener both have chemical reactions with the paint. That much is somewhat similar, but that is where it ends.
Like an epoxy, urethane paint is “Part A”, and the activator is “Part B”, meaning one doesn’t work without the other. Urethane’s are considered 2K, which means it requires 2 parts in order to dry and cure.
1K means, all it needs is air, no other chemicals are necessary for it to dry and cure.
So, in essence, a hardener is really just an additive, where an activator is one required part of a mix.
A hardener just increases drying and cure time in enamel paints. It doesn’t turn the paint into urethane. A hardener does just what the name says.
By it increasing the curing time, it causes the enamel to reach its most peak durability fast. Without it, the enamel can take months to fully cure. In that time, gas, oils and other chemicals can damage the paint.
An activator, through chemical reactions, converts the enamel into a polyurethane compound. This process happens within hours and is highly durable.
Single Stage vs Base Coat Clear Coat
When comparing an acrylic enamel single stage paint job with or without a hardener, base coat clear wins every time.
The reason is, base coats use a urethane clear over them, which is superior in gloss and durability. However, in a comparison of single stage vs base coat clear coat, both in urethane, there is little difference.
I have many times, got a very deep, show quality job out of single stage urethane paints, as you can see. This job was done with Nason Ful-Thane single stage urethane.
However, I have got about the equal in gloss with a base coat clear coat using a high solid clear. You can see the depth and gloss in this example. Based on these images, is it fair to compare single stage vs base coat clear coat?
Best Application for Single Stage vs Base Coat Clear Coat
For solid colors, I feel using a single stage urethane works great. Painting a single stage is actually easier than shooting a base coat clear coat. You have one layer of paint, not including how many coats.
For metallic and pearls, I always use a base coat clear coat. The reason, is for best control over mottling. This means shade variations based on the metallic and pearls blotching together.
Quality base coats, use what is known as basemakers as reducers. All a reducer does is just thin the base coat paint. A basemaker also does this function but with an additional feature.
Basemaker has a stabilizing agent in it, that keeps the metallic and pearls evenly separated. Metallic and pearls without this agent, tend to clump together. This causes light and dark shades in your paint job; this is known as mottling.
When spaying metallic or pearls with a single stage, there are no agents to help against mottling. Usually, a painter will back off from the car, fanning an even mist, to achieve an even look.
So, you can very much paint a metallic paint in a single stage. It just requires a little more effort and attention.
If you plan on doing stripes, flames or other graphics, you will want to use a base coat clear coat. Whatever your design is, once you have it established, just clear it.
Either paint is fine to use, you just have to understand the characteristics of each type. I highly recommend only painting with urethane 2K paints.
To Summarize
When to use single or base. No matter which one, go with a 2K urethane. For ease, cost and looks, use a single stage urethane for solid colors.
For metallic, pearls and any graphics, go with a urethane base coat clear coat. So, it isn’t so much single stage vs base coat clear coat, it is which methods fits what you are painting.
Single Stage vs Base Coat Clear Coat Conclusion
As far as the end result, one paint isn’t any better than the other. It really comes down to the painter’s preference. You can see doing a single stage vs base coat clear coat comparison, is almost pointless.
Most automotive painters, have their methods, techniques and choice of materials. So, they know what works for them. They can tell you how they can get the best look and long-lasting job based on their experience.
If you are going to do a metallic or pearl or flakes, base coat clear coat is the best method.
For solid colors can go either way. If the concern or argument is going to be how to get the deepest look. That will depend on the clear you want to use. If the clear is a regular production 4:1 clear. A single stage urethane will out do it every time.
However, if you shoot a solid color in base coat clear coat, and use a high solid clear. Something like a 2:1 mix, then it can compare or possibly have a better look.
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