General Motors Linden New Jersey locating pin failure

Recap from a prior session. Used as the canonical TPM example — a two-dollar pin that a maintenance engineer never replaced caused several percent scrap. Setup for the broader discussion of acceptable-defect thresholds.

I told the story about General Motors and the failure to maintain the locating pin, which was creating tremendous amounts of scrap. If you look on Wikipedia, they have a whole series of articles on total quality management. There's Theory of Constraints, which we'll go through later, there's Six Sigma, there's Total Productive Maintenance. The General Motors Linden, New Jersey plant was producing several fractions of a percent or several percent of scrap. You'd really like to be down to a few parts per million of defects in your manufacturing process. We'll talk about the tools that people use to measure those things.

Former LFM student Bill Fonte called Tom in to diagnose welding defects at GM's Linden, NJ plant. On-site walkthrough revealed (a) oil contamination preventing electrical ground, (b) a worn hardened-steel locating pin causing fixture slippage, (c) unnecessary galvanizing on an interior hinge causing frosty welds. Each defect was a "hundred dollar bill on the floor" visible to anyone who would walk the line.

If you go and ask for images of quality on Google, this is the garbage you get. What's the content in that? This one has got words in it, Six Sigma — that's a little more content. This image has quality surrounded by a bunch of circles, it looks like a baby's toy. This is why some people say there is nothing of substance to total quality management. In fact there are some things of principle in total quality management. Total quality management also includes total productive maintenance, and I've got some pictures of commercial locating pins.