Geometric Control May Be a Matter of Life or Death! (#286)
(In accordance with the ASME Y14.5-2009 standard)
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I recently had a life threatening event where I had a 1 in 5 chance of surviving. As a result, I had to undergo several medical tests and procedures. The experience really helped me appreciate how important our work in tolerancing of parts is. I have to say that it was reassuring for me as I underwent a variety of tests when I saw that the medical equipment being used was designed and produced by a company where I have trained.
After extensive tests, it was determined that I should undergo brain surgery to biopsy some abnormal growths that were discovered. I did have an experience at one manufacturer of medical devices where I ran into some young, arrogant engineers that I would put in the category of TDKTTDKTTTK - "They Don’t Know That They Don’t Know. They Think They Know". The company was experiencing quality issues. When the surgeon described the brain surgery I would have, I could only picture the poor job of controlling the part geometry that I had observed. I recalled the full color CAD plot that the engineer presented as his tolerance analysis. It was a joke based on a lot of assumptions because they did not understand geometric tolerancing. They had relied on direct tolerancing rather than geometric tolerancing. I pointed out the errors and their egos could not handle it--they thought they knew. I started imagining things that could go wrong and my sick humor kicked in. If the drill which drilled through my cranium did not sense the soft tissue surrounding my brain, the surgeon would drill too deep and my village might get a new parking meter. If the stapler misfired that was used to close the surgical wound on the side of my head, I might end up with a new nose ring which would be OK if that was the look I was after.
So, where am I going with this rant? I made certain the neurosurgeon had the proper credentials. How about if you do the same? Make darn certain the folks you hire to create and read drawings know how to read. In case you didn’t know, there is a National certification of the ASME Y14.5 standard. How about making certain your folks are certified? Most engineering colleges do not teach the subject. That’s right, you hire engineers to read and approve drawings but if it is made to the standards, they cannot read.
I am fighting this health issue with all that I can. Wouldn’t it be tragic if a procedure fails because of a poor design or an insufficient tolerance analysis? Please do not let me down. This message isn’t just for medical device companies. Weaponry our soldiers need is delivered late for the same reasons stated earlier. Not only are lives affected by poor geometric control but also product quality, bottom lines, loss of business to overseas’ competition, corporate reputations, and the list goes on. Manufacturing produces wealth for a nation while a service economy robs wealth. I would like my legacy to be that I helped our country regain its manufacturing prominence. Thanks for listening. I hope to see you next Tip.
