Broken Axles

A colleague of mine was emptying his garage in preparation for his impending new life as a retiree. He was, at some point in his career, working for a major Japanese auto manufacturer in their quality control department. He was part of a semi secretive team of engineers that would investigate mechanical and engineering failures in the vehicles, after the vehicles were released to the public. As he was cleaning out his garage, he came across a memorable file on a particular claim. This is his story…

A dealership had received a complaint of a broken front axle from a customer who had just recently purchased the vehicle. It was a hairline fracture, but nonetheless warranted a look from the engineers. Inquiries revealed that the new owner had driven the vehicle in a normal manner, and was not at fault. As the team continued to investigate the cause of this broken axle, more and more claims of the same nature began to emerge, from all over the country. The volume of damage was steadily increasing. It was not every vehicle, but a few vehicles every month were being tagged as defective, and it was adding up, creating a reliability and PR issue. The team of engineers looked into the possibility that the cars were being damaged as they were being unloaded from the trailer to the dealership lot. They even went to the port, to see if the axles were being damaged when the vehicles were being offloaded from the cargo ships. They couldn’t find anything. They went back to the drawing board, to see if there was a flaw in the engineering design of the axle. Still nothing. they were utterly stumped. after nearly a year of exhaustive investigation, the team of investigators were able to track the vin number of the damaged vehicles to one particular manufacturing plant in Japan. They further narrowed their scope to one line of assembly in the plant. The team of investigative engineers set up a recognizance, and quietly observed the assembly workers on that particular line to “sus” out any malicious intent. They still couldn’t find anything, until they finally narrowed the damage down to one assembly line employee. By all intents and purposes, this employee was doing everything by the book. He would assemble the parts, and per protocol, would use a rubber mallet to gently fit the parts, snuggly together. Upon interviewing the employee, the investigative team found out that this factory worker was also a karateka. The team further discovered that the way this individual was striking the mallet, was causing the hairline fracture in the axles. He wasn’t hitting it hard, he wasn’t doing anything on purpose. In fact, he had no idea he was the source of the broken axles, but the engineers discovered that the “karate technique” he was using to strike the axle with the mallet, was enough to create cracks in an otherwise robust axle.

I typically try to end my blogs with a lesson, or some beneficial wisdom. In this case, this is simply an interesting anecdote in the annals of a karateka, and JDM manufacturing . I don’t know what happened to that factory worker. Was he fired? Was he reassigned? All I know is that this story will always entertain my students.