Here is a pop quiz – if you were to guess how long the average, factory paint job holds up against elemental exposure, what would you think? Two years? Three maybe? Well, according to many automakers – the answer is “forever”. But there is a caveat – you’ve got to keep it clean and protected.
Let’s be honest, most of us are not the best at following directions. If a car is not washed frequently or protected with a paint protection product that can block exposure of harmful contaminants, UV rays, and chemicals, eventually paint damage will occur. And typically, the damage that results are paint oxidation and peeling.
We got a lot of positive feedback from our last series of blogs about buffing a car. So, we’re going to follow the same pattern with this series. This will be the first in a line of 3 blogs on fixing clear coat damage.
But, before we get too deep into advanced clear coat repairs, let’s break down some facts first. In the information below, we’ll explain how modern cars, trucks, SUVs and other toys are painted. And, what causes car paint to fade or oxidation on automotive paint jobs.
Explaining the Modern Paint Job
Old school car dudes like myself tend to be rather vocal about the ‘quality’ of today’s factory paint jobs. But in all reality, an argument can be made that the modern factory paint job is far superior to older, outdated materials and techniques. It’s also more cost-effective, which is really the main objective of today’s business owner.
Essentially, the modern paint job is a four-step process.
Chemical treatment: The first step is to chemically strip all grease, oils, and other contaminants from the bare metal. It’s usually a dip, where the bare metal parts are lowered into an acid bath or sprayed as it travels down an assembly line. Plastic parts that are painted undergo a similar process, but it’s typically a lower-strength acid or base that removes the slimy stuff.
Etching or Sanding: Once the bare metal or plastic is free of debris, the next step is to lightly scratch or etch the material so paint will stick. This is also a spray chemical at most manufacturing facilities.
Primer: As the soon-to-be-painted part rolls down the assembly line of paint prep, the next step is to apply a primer. This serves as the base coat, which sticks to the bare plastic or metal and allows the paint coating to stick to the primer. Again, this is a very quick process, usually involving a few light coats of primer at the factory-level.
Color and Clear: The final step of the paint process is to apply colored paint and a non-colored clear coat of the same type of paint. Most manufacturers spray a few coats during this process, to ensure even coverage.
However, here is an insider secret – generally, the paint and clear coat depth is not exactly level across the surface. In fact – it can vary a few thou, which might seem irrelevant, but that can make a difference down the line.
As the painted parts complete the factory assembly line, its heat treated in the final phase, which accelerates the curing process. Sometimes the painting is completed on an individual part basis, others are painted when assembled. It really depends on the automaker, and the parts that are painted.
What Causes Clear Coat Damage?
So, here is another “did you know” tidbit. When you see that car driving down the street with paint that looks like it’s been sunburnt and is peeling, it’s not the actual paint. It’s the clear coat on top of the paint that’s damaged.
Oxidation is the process in which a metal is exposed to cathodes or electrolytes. However, for the base metal to start the process of ‘rusting’ or oxidation, the clear coat has become penetrated first. There are four primary agents that typically accelerate the degradation of clear coats.
As you can see by the infographic above, there are four main sources of oxidation or peeling paint: UV Radiation, Chemical Exposure, Acid Rain, and Animal Waste.
One of the most misunderstood sources of paint oxidation is assuming that direct sunlight causes oxidation. That’s not quite accurate. While oxidation is produced by the combination of heat and oxygen, the ‘heat’ is derived from UV rays.
As UV light continually hits the clear coat, it slowly penetrates the coating and begins to heat the paint. This introduces oxygen to the under-layer of paint, and as heat is absorbed by the metal, fading occurs.
This is a broad definition. Chemical exposure ranges from those that are manmade to those natural occurring. Certain chemicals agents such as those that make up road salt or de-icing sprays used in colder climates, can slowly eat away at clear coating or painted materials. Once it breaks into the non-protective layer, the chemicals will continue to penetrate until they reach the core.
Using acid or base cleaning agents is also harmful to the clear coat, which is why pH neutral car shampoos or cleaning agents are recommended for washing and cleaning vehicles.
Here is another wide-berth definition. There are toxins in the air we breathe, mainly in the sky above. Sometimes we can see them – and we call it smog. It’s basically unburned carbon molecules that are caused by the burning of fuels, including gasoline, diesel, wood, coal, and others.
When these contaminants mix with moisture in the air, clouds are formed, which then falls to the ground as precipitation. “Acid Rain” is basically the mix of smog and precipitation and can, overtime, cause damage to the surface of any vehicle material.
By any other name – we’re talking bug guts and bird crap here. Both contain acids, which combines with waste and other ‘stuff’ to stick onto your ride. Bird crap specifically is exceptionally toxic, since it’s combined with urine.
What is the Leading Cause of Oxidized Clear Coat?
So, we’ve explained how cars are painted, what caused the coat to be damaged, now what? Well, before we learn how to fix it, it’s important to realize how the clear coat started to peel up in the first place.
To be honest, your cars paint job is very similar to your skin. It has multiple layers, with those on top susceptible to damage that essentially is caused by drying. All the contaminants listed above, UV Rays, chemicals agents, acid rain, and bird and bug stuff all cause the clear coat to dry.
When the clear coat begins to dry, like your skin, it begins to flake or shed layers. This is what causes the clear coating to begin the oxidation process.
Can You Repair Oxidized Clear Coatings?
There are multiple levels of damaged clear coats. Depending on when you discover the damage, will determine the ability to repair. Here are a few examples.
On the right side of this image you can see the first sign of clear coat damage. It’s when the top layer is starting to dry out, which causes the paint to appear cloudy. Basically, it’s comparable to a small sunburn – just apply a little moisturizer and you’ll be good to go. In this case, the moisturizer for clear coat would be a natural carnauba wax. It can – in some cases, rehydrate the clear coating with oils found in the wax.
When the clear coat has passed the level of simply drying or fading, small pockets or thinner layers of the clear coat will begin to spot. At this point, the upper layers of the coating are damaged, and need to be removed to a point where the clear coat is no longer damaged. This is where paint correction begins.
If the clear coat has begun to peel as the image above shows, you’ll have to remove the damaged portions of the clear coat and reapply a new coating.
This is where we’ll pick up our next blog in this series. We’ll discuss a few ways of determining whether you should attempt a DIY repair of oxidized clear coats or save your pennies to have a professional paint shop do the work.