We spent some time at D-Ham watching the General build pre-production "pilot" cars used to calibrate the line and work out any kinks in the assembly process. None of those cars can be sold to the public, but they are identical to the Volts you'll see on the road.

Above: It all starts with a steel unibody assembled by robots using body panels stamped at GM factories in Flint and Lansing. There are more than 900 robots in the body shop at D-Ham, and they can make 285 welds in 14 seconds.

Volts roll down an assembly line that stretches 24 miles through a factory that covers 3.6 million square feet. (That's about 62 football fields, including end zones.) The cars are built alongside Cadillac DTS and Buick Lucerne sedans in a factory that employs 1,048 people. It built 35,764 cars last year.

GM plans to build 10,000 Chevrolet Volts in 2011, and they'll all come out of D-Ham.

Photo: Jim Merithew/Wired.com

Authors: Chuck Squatriglia

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