July 26, 2023
[starbox] For something that causes so much trouble for so many people, you would think there would be lots of consideration given to the unforeseen consequences of decisions. This topic came to mind after reading an article on how lucky baby boomers were to have survived to adulthood, given the dangerous behaviors we and our parents engaged in. Imagine trying to get approval to sell Lawn Jarts today! At one time half the population smoked and they smoked everywhere. I recall people lighting up in church! Drunk driving? In my home state of Wisconsin it was almost a competitive sport. Seat belts? Who needed them!? Air bags? We don’t need no airbags! Just brace yourself against the dashboard. I came to look for unforeseen consequences as part of my training in machine design. Assigned to “detail” custom machine parts for a crotchety old German engineer, I was expected to have a reason for every feature, dimension, and tolerance on a drawing. Occasionally I would have to “fill in the blanks” on a section of the machine that did not interest the engineer. It might “only” be a pump drive or an access cover, but when I designed something not only did the usual drawing review questions get asked, but another level of query appeared. And that level was “What if this happens?” We have all heard the horror stories of engine mounts needing to be disconnected to change spark plugs; my “teacher” was all over those situations — way back in 1971. Insuring maintenance access, planning for fast repairs and replacements, and anticipating operator abuse were among the things he was concerned with. Just having lifting holes, access holes, or jackscrew holes in the correct places can shave hours off critical repairs — at almost no additional cost. I have used this multilevel questioning on myself and my “students” over the years with excellent results. Those instances where we lost focus and skipped design reviews were where we often had expensive rework to do, or spent more time in assembly and test. It is better to spend three hours in design review in an air conditioned office than a long weekend fixing something on a field service trip.