Building a new '14 Corvette requires skills akin to those of a musical conductor. Hitting all the right notes involves a multitude of engineering artists and mechanical instruments, all working in harmony. Amazingly enough, you can see this virtuoso performance take place for the paltry sum of $7.
That's price of admission for a tour of the Corvette assembly plant, established in 1981. The facility is located on 221 verdant acres in Bowling Green, Kentucky, around an hour north of Nashville. Last year, some 50,000 admiring Corvette admiring fans strolled between the yellow lines laid out evenly on the spotless, polished factory floor, which covers more than one million square feet.
Of course, visitors don't get to see every foot of the facility, since certain areas such as the waterborne-paint booth are off limits to avoid inadvertent contamination, or involve harsh chemicals, such as the chassis ELPO (Electrolytic Dip Plating Operation). And visitors must keep a safe distance away from the assembly line to avoid what the plant managers call, with admirable frankness, "mutilation damage." Even so, you can still get a good overview of the size and scope of the operation. (By special request, you can even follow along and watch your personal Corvette being built.)
For the purposes of this feature, we were treated to a somewhat more in-depth tour, so even if you can't make a pilgrimage to southern Kentucky, you'll find some additional detail here that most visitors don't see. First, a bit of background leading up the C7's new assembly line.
When the 215,213th and final C6 Corvette rolled off the line in early 2013, tours were halted. The teardown of the old production line, some of which dated back to the C4 era, commenced immediately, in order to make room for a number of upgrades in production.
About a year later, and after $131 million invested in tooling (with $52 million spent on the body area alone), along with improvements in lighting and streamlining, Corvette production was up and running again, assembling some 1,725 major parts from 320 different suppliers. Also new to the facility is the previously Wixom, Michigan–based Performance Build Center, which currently handles GM's crate-engine program.
The entire operation is headed up by plant manager Dave Tatman, who also provided the orchestral analogy noted at the outset. "We make dreams come to life" is a phrase Tatman personally emphasized during our tour, and which is emblazoned on the assembly plant's wall.
Assisting in this oneiric transmutation is a new on-site welding capability. Tatman acknowledged that previously there was a bit of resentment on the assembly line at having to bring in aluminum frames from another factory. Now, workers can note with pride that they're made in-house.
Not only that, the technology has improved, with the first production use of a GM-patented process that allows aluminum to be spot welded to aluminum. The result is the strongest and most precisely built Corvette in the car's six-decade history. The new aluminum-welding process enabled GM technicians to make the frame lighter and stiffer, improving both performance and driving confidence.
New technologies also enable more accurate and efficiently produced subassemblies, specifically on the frame and the components attached to it. Assembling the frame requires more-advanced joining processes and more-precise inspection methods to ensure strength and dimensional accuracy. That's where aluminum and laser welding are instrumental, along with Flowdrill-type fastening.
The latter process, a GM first for joining body structures, consists of 188 fasteners with structural adhesive, installed by a high-speed drill that extrudes the frame material to create a strong, integral collar that is tapped for screw-type fasteners. Flowdrill fastening is employed on closed sections, where only one side has open access and where arc welding could cause heat distortion or weaken the material. Dimensional quality is also maintained, eliminating the need for post-assembly machining.
Further precision results from laser-based, three-dimensional inspection systems, which verify that overall assembly tolerances are 25 percent tighter than the previous-generation Corvette. During our walk-through, we spotted an intricate-looking jig fitted with a multitude minute pads. Called the "Perceptron," it confirms the exact location of hard mounting points for the body panels.
"Many customers will never see the advanced manufacturing technologies used for the new Corvette Stingray," notes Tatman, "but they will appreciate the benefits of these technologies every time they get behind the wheel. "Measuring 100 points on every frame reduces the chance for unwanted squeaks and rattles that would distract from the driving experience."
With all the changes at the Bowling Green Assembly Plant, some 250 new jobs were created (totaling 816 employees in all), and many GM workers from other areas specifically requested transfers there for the prestige of building the new Stingray.
This added workforce is obviously a boon to the local economy (the state claims a $53 million total impact for 2012), but it doesn't stop there. The General Motors Foundation provides grants totaling $75,000 to support programs at 11 area nonprofits and organizations, the third consecutive year that the foundation's Plant City Grants have been awarded. So all told, this Stingray symphony is music to everyone's ears.