Some time ago I wrote a series of posts about ShortRun SPC. You can read them here, here, and here. Recently a reader added this gracious comment to one of the posts:

Hi, Im working in a short run / high mix products metal mechanic process.
Your articles are very interesting. part of my job is launch SPC. So I would like to have a good start, in the past, only few trials with XR charts, that were not good enough.
Any help and suggestions with Short Run SPC s welcome

As I thought about what advice I might offer to someone just starting out, I realized I have some ideas, but I wondered what my other readers would suggest. So I’ll tell you what I think and invite others to add comments.

My advice is to start small and keep it simple. This is probably not what you’re expecting from a data head who brings a comprehensive enterprise SPC Software solution to the table. But you need to build trust and confidence that SPC, especially ShortRun SPC, bring value to your organization. Pick one process and one key metric to track. It should be one where you’re pretty confident that you don’t need to code out the Range chart.  That will help you keep the math simple, and make the overall effort more explainable to everyone.

I suggest you commit to charting this process manually for several days or a week. Start with a simple ShortRun control chart and subtract the target from each value you record so that your target line is zero. When I say chart this manually, I mean (gasp) use a pencil and a paper control chart.  Write it down. It will take longer, but in the end you’ll understand the process better and you’ll be able to defend whatever conclusions you come to. Once you have the chart, treat it like you would any other control chart and see what it has to teach you about the process.

So that is my advice. What, dear reader, would you add to this? Have I overlooked something? Use the ShareThis button below to mark this page, or leave a comment,  schedule a conversation, or call 800-958-2709.


  1. Larry Coburn October 31, 2012 at 8:41 am

    Pick a champion that wants to do this type of SPC work. Make sure they have enough time to make it a top prioirty. Have weekly update meetings to ensure it feels like an important project. Give out kudos for everyone taking the inititive to get involved and make it happen. Meetings on the subject must happen the same time every week rain or shine regardless of those in attendance. (translation this is important) Widely publish the benifits of the ShortRun SPC work.

  2. Evan Miller October 31, 2012 at 9:29 am

    Great comments, Larry. It’s all about consistency and leadership.

  3. Mark Lindsay November 1, 2012 at 11:57 am

    Paramount to making short-run SPC work beneficially is thinking PROCESS rather than product. Known differences [typically, product differences] are coded out of the data via short-run techniques. Most situations where short runs are conducted occur at stations or machines that are in operation long-term. Improving that long-term process is the real goal; short-run processes will improve as that happens.

    I agree with Larry’s comments above regarding the need of a champion wanting to do “this type of SPC work.” An important part of “this type of SPC work” is thinking process and helping others to think process allowing the data to guide.

    In support of what Evan wrote regarding starting with one characteristic and learning how it can best benefit, I recall Dr. Deming answering a plant manager who had stated they had 130 active SPC charts and was wondering what the appropriate number might be for a plant that size. The answer was, “ONE! …the one you are using.” Always rewarded is preliminary planning and honestly answering, “What should we measure and track?” [In the early days, too frequently the question was asked, “What can we measure and track?”]

    I would start by listing and prioritizing the processes (not products) that are common to the plant. For the highest priority process, answer the question, “What should we measure and track?” This question may also be asked as, “What metric would we most like to improve?”

    • Evan Miller November 1, 2012 at 12:33 pm

      Thanks, Mark. So much of this is about thinking differently. With ShortRun, not only do we have to begin thinking about variation differently, we also have to boil it down to the critical definition of what measurement will help us understand the process? Your point about “should” versus “can” is also really important. From a software perspective, we CAN measure everything, but we’ll be far better off if we only measure what we SHOULD.

  4. Jay Bronec November 15, 2012 at 7:21 pm

    Adding on to Dr. Lindsay’s comments, “what should we measure and track?” you should also ask the question “why should we measure and track?” SPC to satisfy a customer requirement is not a strong enough to sustain long term success. It might get the program kick started but there needs to be an internal driver. Who and what department drives the implementation will determine the level of traction the program receives. Again this is Mr. Miller’s and Mr. Colburn’s point but there is a big difference between the Director of Quality championing the implementation versus the VP Operations. As for the details of the implementation starting small is highly recommended however I would integrate as much as you can early. That is if you are going to eventually connect to a business system to get rich product traceability but IT is 6 months out; have them populate a “sample” table that you can use for testing. IT will see how easy the complete integration is and will probably do it right away. The more you integrate the faster it will grow. The nice thing about GainSeeker is the sky is the limit whatever you can dream it can do!

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