As a quick review, Takt time is the customer demand expressed in a time target. As a result, it becomes the “rhythm” of a Lean line.

In a perfect Lean line, every operation (labor or machine) would take place in exactly one Takt time. Regardless of the number of operations, one finished product would be completed each and every Takt time. Unfortunately, the real world seldom cooperates:

• Some operations stubbornly remain batch
• Variation exists in the ability of different people to do the same task
• Mixed model production introduces differences in work content
• The concept of Takt has special meaning in process industries (more on that in an upcoming Operational Excellence Insight)
• Process capability is not always able to overcome minor variations

As Lean Manufacturing Consultants we’ve seen many facilities and, if that Holy Grail of a perfect line really exists, we have yet to see it.

That doesn’t mean that there aren’t some outstanding Lean lines that operate very effectively. But the teams responsible for the best lines have responded to those pesky real world obstacles with detailed analysis, creativity, and often several cycles of continuous improvement.

One person who e-mailed to us has a situation that is not too uncommon. He works for a true “built to order” business, otherwise known as a job shop. His company produces high tech, one-off products based on unique designs. We’ve worked with many similar job shops over the years. Often, the nature of the products means that yearly production volumes change dramatically based on the complexity of orders. A particular company we worked with in the past might produce 60 “simple” units one year and 12 complex units the next year. How can Takt time apply to this environment?

In this situation an approach that we have used is to look for common processes. Even if the end products are different, there are usually blocks of work that are very similar, if not identical. Often these common processes have already been identified and are used as modules to develop pricing. Complex units typically use more of the modules than simple units. In many cases it is possible to develop building blocks of Standard Work or even Lean workcells that perform similar types of work in repeatable fashion.

Once common processes have been identified, it may be possible to establish Takt times for these modules of work. In keeping with the principle of Continuous Improvement, after some initial areas are identified, more patterns of commonality begin to emerge.

One caution about using costing data is that while it may be OK as a way to identify common modules of production, be very careful about utilizing the times in cost data for any Lean purposes. The reason is that it is difficult to know what assumptions may be layered into costing data and it may include everything from rest allowances, other indirect labor, or vaguely defined efficiency. As with most time measurements in Lean, it is far better to personally “go and see”.

Do you have any tips or advice to offer others in dealing with Takt time issues?   Please visit our blog to add your comments by following the link: Our Blog.

Interested in more ways to improve operations and increase earnings at the same time? We invite you to download our white paper “Targeted Lean Six Sigma". You are also welcome to browse the list of free white papers and other articles at Free Resources.

If you have a topic that you would like addressed, or an Insight you would like to pass along, e-mail us at: Jack.Rink@rmdonovan.com

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