OCBen

Porsche borrowed these statistical methods from the Japanese who in turn learned them from the American, Deming, who taught the Japanese SPC (statistical process control) which allows for periodic sampling of product to ensure conformance to quality standards of deviation, which eliminates the need for 100% testing. Statistical methods in manufacturing have been refined over time with the current goal of zero defects as embraced by the Six Sigma philosophy of quality control, though it still boils down to the statistical mean and the standard deviation of a process which Deming helped pioneer.

You say that like it's a virtue for a car to be put together the old fashioned way -- mainly by hand.

The fact is, the opposite is true: the more automated the assembly process, the higher the quality of the final product, as borne out by statistics. It's been long known that humans make poor quality assemblers when working on an assembly line repeating the same monotonous task time after time -- human errors are inevitable. Not so with machines. But human labor is cheap compared to the high capital investment cost of sophisticated robotic machinery.

It's no stretch to assume that Porsche, with the huge profits it was earning, invested heavily in automated processes to take out the human factor where you don't want it, and leave it in where you do. If you saw the NatGeo documentary on the Chevrolet assembly for the Z-06 you'd see more hands on the assembly line putting that car together than was seen for the 911. So one can logically draw the conclusion that the quality of an assembled Chevrolet suffers because of the number of "hand built" assembly operations it undergoes.

The ultimate goal of modern manufacturing is to eliminate the human factor -- the assembly laborer -- and do it all by tireless, precision machines. Just try getting the powerful labor unions to sign off on that idea.

Edgy01

Ben--thanks for summing this thread up nicely. It's funny how little America appreciated W. Edwards Deming. It took the Japanese to do this.