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76 The PCB Magazine • September 2014 by Steve Williams steVe williams Consulting llC Best Practices 101, Part 2 C o l u m n poiNt of View A few months ago, Best Practices 101, Part 1 (May, 2014) was rolled out, focusing on pro- cess analysis as the first step in this process. This issue will discuss another powerful tool at our disposal: value stream mapping. "But we already made a process flowchart— isn't that good enough?" In a word, no. Process flow diagrams are a great first step, but they don't tell the entire story. Value stream maps add one critical in- gredient that standard process flowcharts don't have: time. Process flowcharts, whether drawn by hand or electronically, do not capture this important element. They simply present a snap- shot of the sequence of steps in the process. Time is essential to understanding how one op- eration affects another and where your resourc- es are being spent. Value Stream Mapping A value stream map (VSM) takes the basic flowchart to the next level, kind of like a pro- cess flowchart on steroids. In addition to the ba- sic action boxes with arrows showing the flow of work, a lot of other information is added, in- cluding material and information flow, operat- ing parameters, process lead-times, inventory, a timeline depicting value-added time relative to non-value added time, and so on. Value stream mapping is the single most effective major pro- cess analysis step to identify the value stream, and conversely, the non-value waste in your processes. The value stream is the set of all of the specific actions and activities required from the beginning of a process to the end of a pro- cess. Imagine a long and winding deep blue stream flowing through cities, counties, and states. Next, visualize all the things that the riv- er carries within it: water, fish, minerals, plants and a thousand other elements that combine to form the stream. Processes are very much like a stream; they flow in a natural direction and carry materials and in- formation within them from one point to an- other. The activity of value stream mapping is the core fundamental method of identifying the areas of waste which can be eliminated within any process. By finding the sources of waste and quantifying them, action plans for reducing or eliminating them can be prioritized. Apart from identification, value stream mapping can also help to streamline a process for higher produc- tivity and efficiency. Each process needs to have a beginning and end clearly identified before this can occur. This sounds simple, but since many of these discrete processes often run to- gether, it is critical to define the boundaries of the process from a value stream standpoint. Only through a detailed process analysis can you identify the non-value added steps that have become accepted, unquestioned parts of the process that result in "the way we have al- ways done it." There is what I call the value stream map paradox: Value stream mapping is the most ef- fective Lean tool for identifying high payoff opportunities, yet value stream mapping is the Lean tool most likely not to be used by compa- nies doing "drive-by Lean." Value Stream Mapping Steps Value stream mapping brings together Lean concepts and techniques and helps to avoid the "cherry-picking syndrome," in which processes