There are four main types of scratches you can get on your vehicle: clearcoat, base coat, primer, and bare metal. Each represents a different level of depth and damage to your vehicle’s paint and eventually, your vehicle’s body.
Some sources only classify three types of scratches and bundle the base and primer layers into one, but it is easier to explain and classify depth scratches according to each layer of a vehicle’s paint
Layers of Vehicle Paint
To understand scratches better, it is important to understand that there are three or four different layers that comprise a vehicle’s paint. For a three-stage paint job, there is a clearcoat, base coat, and primer.
Some vehicles utilize four-stage paint that includes an additional layer called the E-coat, short for electrophoretic coat. Even though some vehicles use this, it is not as widely used in the automotive industry as in others.
The clearcoat layer of paint is self-explanatory. It is the outermost, clear layer of paint applied to your vehicle. It acts as a shield for the next layer of paint – the base coat – and it helps give the colored paint its shine. It is also the thickest layer of paintwork.
Being the outermost layer, it is where most scratches occur, and it is quite easy to damage. Improper washing techniques, certain types of car washes, extreme weather exposure, and even everyday use can all wear down or damage the clearcoat of a vehicle.
The base coat, or base color coat, is the middle layer of paint in a three-stage paint job. It is the coat that gives color to the surface on which it is applied.
Additionally, if any other characteristics are desired within a specific color such as color-shifting elements, other metallic elements, or sparkles, they are added here.
The base coat is often one of the thinnest and most fragile layers of paint since a thicker base color coat often causes inconsistencies in the paintwork.
In a three-stage paint job, the primer is the lowest layer of paint and is the first coat applied directly to the bare metal. It is also a thin layer, as the base color coat, but its primary purpose is to create a surface on which the color coat can stick.
This used to be more important in the past as manufacturing processes were not as refined as they are now, and the primer served to create a better, more uniform surface for the paint.
Types of Car Scratches
Car scratches and their severity are defined by how deep into each paint layer they go. Each type corresponds with a different paint layer and requires different repair methods.
Clearcoat scratches only penetrate the outermost paint layer of a vehicle. They are the most common since the clearcoat is the layer exposed to the outside, paint is fragile, and so many things come into contact with the clearcoat.
Swirl marks are the best example of clearcoat scratching. They usually occur during car washing when improper materials are used or dirty cloths are used to scrub the vehicle’s surface. Other things like acid rain, road debris, and polishing can also wear away the clearcoat.
Clearcoat scratches are the easiest to fix since they do not necessarily require anything to be applied or removed to correct. Paint correction or polishing is the best way to remove these types of scratches.
Paint correction and polishing include grinding down a small portion of the clearcoat to smooth its surface. During this process, some of the materials used to polish can also fill in the deeper scratches not removed by the polishing process.
Paint correction can also eliminate light oxidation. Even though oxidation is not technically considered a scratch, it does eat away at the clearcoat over time.
Additional clearcoat scratch removal methods include scratch removal paste which can be found in most retail locations. Ultimately, these are no more than localized polishes that can be applied to small areas quickly with little to no preparation. They are a good alternative for isolated, localized, surface-level scratches that occur from small rocks or other debris that may graze the surface of your vehicle.
Wax and ceramic coating can be applied over the clearcoat of the vehicle in an effort to mitigate clearcoat scratching. These essentially provide a fourth layer of paint protection, albeit not a permanent layer.
Base Color Coat Scratches
A base coat scratch is a scratch that penetrates through the clearcoat and into the base color coat. This type of scratch can be caused by physical objects that hit the vehicle and chip the paint or from severe oxidation that has completely worn away the clearcoat.
Base color coat scratches are much more difficult to correct than clearcoat scratching. Since they penetrate the clearcoat, there is no easy way to effectively and quickly fix these types of scratches.
There are several DIY products available in automotive retail locations that attempt to allow the average vehicle owner to fix these types of scratches, but the results are often less than optimal.
It is recommended that a professional automotive repair shop repair base coat scratching as the leveling process requires total clearcoat removal to reach the level of scratching. These shops will also have the necessary equipment to deal with this type of damage.
Primer scratches dig into the lowest layer of paint before no paint is left at all. Because of this, a scratch that digs into the primer is the hardest type of scratch to fix efficiently and uniformly as far as paint is concerned. Most primer scratches come from a larger piece of debris, a rock, or something like a belt buckle rubbing against a body panel.
Even though fixing primer scratches is not impossible, it is very difficult and should probably be left to a professional, given that the damage is extensive enough.
Products like color pens or touch-up paint are available as a quick fix in many retail locations, but this is designed as a quick and temporary measure for the larger problem.
The clearcoat and base coat would be gone at the site of a primer scratch, making it very easy for a quick fix to become undone or spread.
Bare Metal Scratches
Scratches that penetrate all the way through each paint layer to the bare metal of a vehicle are the most damaging and hardest to fix types of scratches.
They can require extensive repair work including an entire panel or vehicle repaint depending on the extent of the damage. If a scratch penetrates to bare metal, rusting is the greatest risk to the vehicle. When this occurs, it becomes much more than just a paintwork issue.
When bare metal scratches occur, a body shop will likely be the only viable solution for a fix. If the scratch or dent is small, touch-up paint could be used as a temporary measure, but it will provide little long-term viability as the lack of primer and clearcoat protection will make any quick fix almost useless.
There are four main types of scratches: Clearcoat, base color coat, primer, and bare metal. Each corresponds to how deep the scratch goes, and each scratch type corresponds with each layer of paint a typical car possesses.
The deeper the scratch is, the harder it becomes to fix well, efficiently, and completely. Regardless of how deep a scratch on your vehicle might be, it is always a good idea to consult a professional about how a fix should be approached, especially if the scratch damage is extensive.