Is it possible to assemble a car with glue?

Many automakers, including BMW, have used automotive structural adhesives in place of bolts or welds to attach plastic cladding to vehicles. See our car engine image gallery.
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When you imagine the assembly line at an au­to plant, you probably picture welding machines, rivets, bolts and screws fastening all the parts of a car together. You might be surprised to learn that many automakers are using glue to bond some parts together on modern vehicles. This isn't the kind of glue you'll find in a school kid's backpack, or the kind of car glue that you might use to assemble a plastic model -- automotive structural adhesives are advanced materials called epoxies that can be customized to bond to almost any surface and endure a wide range of temperature extremes.

Using glue in auto manufacturing isn't a way to cut corners or make an inferior car. Modern adhesives offer a lot of engineering advantages over traditional methods of fastening two parts together. In fact, adhesives usually form a bond stronger than the materials they're bonding together. Adhesives could be the key to building lighter, more efficient cars, and when new materials such as carbon composites are used, adhesives might be the only way to bond them as carbon fiber panels cannot be welded together.

Of course, auto adhesives aren't perfect -- there are a few environmental concerns and some applications for which they just don't work very well. Which adhesives work best for the many different parts of a car? And how will the use of adhesives change the auto industry? As a result, will we see less expensive cars? If so, will they be safe? Keep reading to find out.