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14 The PCB Magazine • April 2016 is learning how to properly design experiments to identify the optimal operating parameters for the target process. Selecting which variables to monitor and optimize is critical. One must first do the right things and then do things right. Pick the wrong ones and the data collected will likely be meaningless. And this begs the ques- tion: How does one choose variables to monitor in an experiment? We are fortunately living in a time when there are oceans of experience in most of the processes used in circuit manufacturing, so tap- ping into that experience is important. There is no benefit in repeating experiments that have been run countless times before. In this regard, it is very important that the process engineer be at least as much a reader as an experimentalist. Running experiments is useful and can be en- grossing but if the answers are known by others, it is better to tap into their knowledge base. There is the old story of the successful in- dividual who was queried as to the most im- portant factor in their success. The two-word answer was "good experience." When pushed to explain how one gets the necessary good ex- perience another two-word answer was given: "Bad experience." This apocryphal story was no doubt concocted by someone who understood the importance of learning from experiences and of the importance of failure. If we, in our infancy, were afraid of falling on our behinds as we departed infancy and attempted to walk, we would still be crawling about on our hands and knees. To this end there is the reminder from another sage, the early 20 th century poly- math and philosopher, G.K. Chesterton, who wrote: "Anything worth doing is worth doing badly." What is missing and must be inferred as an addendum to his message are the words, "…at first". There is nothing wrong with mis- takes; mistakes are how we learn. However, if one has the resources available to them to avoid mistakes, then it is folly not to avail one's self of that information. For the astute PCB process engineer, resourc- es abound. There is a treasure trove of legacy information to be found in trade magazines, in academic journals, blogs, columns, supplier websites and industry specific texts. While on that thought, it is worth noting that The Printed Circuits Handbook, now in its 50 th year, has just been released in a 7 th Edition, edited by PCB industry icons and gurus Clyde Coombs and Happy Holden. The tome has been both a bible and a source of intelligence for preparing battle plans for process engineers since its first edition and has been translated into several different languages. It arguably should be found on the reference bookshelf of any competent PCB ven- dor and more importantly it should be read... There are, of course, numerous other re- positories of process knowledge available. One easily overlooked are the individuals who represent the process or equipment de- velopers. These individuals are the honey bees of the industry who help cross pollinate those within the industry with new ideas, transferring knowledge and experience be- tween manufacturers to the betterment of all. In summary, process engineers serve a vital function on the front line of printed circuit manufacturing. They are often, if you will, the "Delta Force" that subdues and controls that which is one of the mortal enemies of manu- facturing…process variation. The intelligent process engineers should avail themselves of all of the tools they need to complete their mis- sion. To that end and in reference and support of that last thought, it is highly recommended that the reader of this piece read the series of columns being prepared by Happy Holden for I-Connect007, titled "25 Essential Skills for En- gineers." Holden's near half-century of experi- ence and accumulated knowledge as PCB pro- cess engineer and manager are too important to let pass by unread. PCB Verdant Electronics Founder and President Joseph (Joe) Fjelstad is a four-decade veteran of the electronics industry and an interna- tional authority and innovator in the field of electronic interconnec- tion and packaging technologies. Fjelstad has more than 250 U.S. and international patents issued or pending and is the author of Flexible Circuit Technology. He is a frequent contributor to I-Connect007 publications. proCess engineering: pCb manufaCturing's "Delta forCe"