How Automotive Finishing Works

Man in shop painting black car
Image Gallery: Car Safety The application and types of finishes on your car not only maintain its aesthetic value, but they also protect it from damage. See more car safety pictures.

Take a good look at the car parked in your garage. Ever wonder how it got there? Well, sure, you parked it there, but think about it: There are millions of vehicles on the road today. From the metals welded together to create the vehicle's body to the coat of paint covering the finish -- what exactly was involved in the production process to get them to consumers?

Once you start looking at the cars on the road as products that were designed and manufactured, rather than simply as tools for getting around, you begin to get a picture of the sheer size of the auto manufacturing industry. It's a big business: Automobiles are in high demand in many parts of the world, and they all have to come from somewhere.


Automotive manufacturing is a big topic, so for this article, we're going to focus on what goes into the vehicle's most visible part -- the paint -- which helps protect the rest of the car. Whether you're driving a vehicle that's fire-engine red, glacier white or plum crazy purple, odds are good that you're driving a car with plenty of paint on it. But how is that paint applied and protected so your car can keep looking good? And is that paint there simply for aesthetic purposes, or are there other reasons to have that shiny coating on your car? Keep reading to find out more about how automotive finishing works.

Up first, we'll take a look at the different technologies used to finish your automobile's coating.


Automotive Finish Technologies

People often think about paint when they think about the outside of their cars. After all, many people feel like their car's paint color says a lot about them as a person. Various paint companies report that neutral colors such as black, silver, gray and white are the most popular both in the United States and worldwide.

Although a car's paint is what stands out, it's just the tip of the iceberg when it comes to the finishing process in automotive manufacturing. Carmakers can't think about just the paint; if they did, there would be a lot of unprotected car paint out there. Think of it this way: We've all seen houses, even some fairly new ones, with chipped and peeling paint. Automotive paint, however, generally holds up pretty well, even though cars get driven in all sorts of weather and hit with all sorts of debris.


The reason automotive paint tends to last long is that it's just one step of many involved in the finishing process. Most factory car painting is also done by robots to ensure a uniform application and to get the job done quickly and efficiently. The application of the paint is very important. It needs to go on the body of the car smoothly because bubbles or ripples end up weakening the paint. Robotic equipment is best at getting a solid, uniform coat of paint on the car, so it's an important aspect of automotive finishing.

In addition to the application, the other key to finishing technology is the chemistry that goes into it. Not only do carmakers need paints with rich colors, but the paints have to be able to withstand extreme conditions. Car paint has to be able to look good after being left in the sun for days on end, coated with ice-melting chemicals and driven through dust or hailstorms.

Keep reading to learn more about recent advances in the chemistry of car paint and automotive finishing.


Advances in Automotive Finishing

Sunlight shining on car in field
A clear coat protects the car and its paint from the sun's damaging ultraviolet rays.

Most people probably don't think about it, but advancements in automotive finishing are some of the most important improvements in automotive manufacturing. Cars today generally have the same basic parts as the first cars to roll off Henry Ford's assembly lines. The paint doesn't look all that different (except that you have more color choices), but automotive finishing these days involves technology far beyond anything that would have been on a Model T.

Some of the biggest advancements are not in the paint, but in the sealant, or clear coat, that carmakers put on top of the paint. Clear coat protects the paint from the sun's harmful ultraviolet rays. In some cases, the clear coat goes directly over a car component. For example, in the case of the Chevrolet Corvette ZR1, the clear coat went over exposed carbon fiber panels with no paint.


Clear coat not only protects the paint from the sun, it also acts as a suit of armor for small dings and scratches -- it takes the hit instead of the paint, since a scratch in the clear coat is much less visible than a scratch in the paint. In one of the most recent advancements in automotive finishing, Nissan developed a self-healing clear coat for one of its luxury brands [source: Gable]. With the self-healing clear coat, small scratches fix themselves in a matter of days. The clear coat uses an elastic resin. When a space in the coating is created by a scratch and it's exposed to sunlight, the coating fills the space. That keeps the paint below the clear coat safe and the car looking good.

Read on to learn how automotive finishes can protect your car's value.


Importance of Automotive Finishing

It's easy to think of automotive finishing as a frivolous step when it comes to automotive manufacturing. After all, the paint doesn't make the car go. It's just for looks, right?

Actually, automotive finishing is one of the most important parts of auto manufacturing. Sure, the paint makes the car look good, which is important to car buyers, but the car's paint and all the protective coatings on it are important tools for protecting the car's value, and the car itself.


Although cars are made of strong metals, those metals still break down over time, especially if exposed to water, heat or harmful chemicals. Paint helps slow the breakdown of the metals in the car. Even parts of the car that aren't painted -- such as the undercarriage -- are sealed with a protective coating as part of the finishing process. Protecting the paint with clear coat helps protect the metal underneath even more.

You've probably seen old rust buckets sitting in someone's yard or on the side of the road. A car is only as strong as its metal, so if a car's body is rusting, and pieces flake off when you touch it, how is that car going to hold up in an accident? Chances are good that it won't. Also, a car is a big expenditure for most people, so in addition to boosting the car's safety, a protective finish helps keep that financial investment from rusting away. Having a cool-looking car is just the icing on the cake.

Learn more about automotive finishing and other car manufacturing processes by following the links on the next page.


Lots More Information

Related HowStuffWorks Articles

  • Fishman, Charles. "No Satisfaction at Toyota." Fast Company. December 19, 2007 (December 16, 2009).
  • Gable, Chris. "Infiniti Launches Self Healing Paint." Wheels. August 21, 2007. (December 16, 2009).
  • Ramsey, Jonathon. "Nissan's Self Healing Scratch Shield Paint to Be Applied to Mobile Phones." Autoblog. November 27, 2009. (December 17, 2009).
  • U.S. News. "Silver is Most Popular Car Color, Yet Again." U.S. News Automotive. October 2, 2009 (December 17, 2009).
  • U.S. News. "Black is Most Popular Car Color Worldwide." U.S. News Automotive. December 2, 2009. (December 17, 2009).