Leading the Change 447
Chapter 20. Leading the Change 447
this expensive and knowledgeable mentor to create the showcase that would get the plant visibility throughout the company. But when push came to shove, he went with what was familiar and comfortable to him. Going to the floor to see for himself, to truly understand, was not within his definition of a plant manager’s responsibility, and was not comfortable.
2. There’s a difference between a vendor and a strong technical partner. Clearly, the A1 line benefited greatly by working with Toyoda Machinery Works. The X10 team selected the same types of machines that were currently making bad parts on existing lines— with no root cause yet identified—supposedly to get “commonality.” They picked separate jigs and fixture makers because of price and locality without considering the complex interactions between these and the machines themselves. Yoshina, as an experienced practitioner of the Toyota Way, knew that spending a few dollars more on good tooling and jigs now would yield a lower total cost over the lifetime of the product. While the X10 line was created by mixing several brands of machines in a way that had caused problems in previously installed X10 lines, the A1 group relied on the experience of Yoshina and TMW as to what machines and processes to utilize in manufac- turing the pistons. Yoshina and TMW were able to draw on a vast database of machines and processes that would robustly accomplish the piston manufacturing task at hand.
3. There’s a difference between learning TPS conceptually and deeply understanding. This company had been doing lean training for years, and the vocabulary of TPS was well known. But there were specific challenges in machining that were not well understood. It was clear that the engineering teams were struggling to make the right technical choices despite their experience as engineers and having gone through TPS training.
A major difference between the X10 and A1 lines that probably led to many of the quality differences between them was how the tooling moved. The X10 tooling moved vertically, with the part clamped in the x-y plane. Due to the force of gravity, all chips and coolant would fall onto the tooling, leaving them on the parts. Over time these wastes would build up and become a big contrib- utor to defective pistons. In contrast, the A1 tooling moved hori- zontally, with the part clamped in the y-z plane. With this design, though the chips and coolant would still fall due to gravity, it would not fall onto the part, but into the chip separator, for the coolant to be reclaimed and the chips recycled. This is a subtle technical difference that requires the kind of attention to detail characteristic of the Toyota Way.
Another example of the technical differences between the two lines was the misapplication of the concept of one-piece flow by the X10 team. By applying the idea too literally in a machining environment, several things happened to the X10 process. First, the operator was underutilized. In a machining environment, an operator’s primary job is to check quality, change tools, and perform minor troubleshooting while picking up processed parts from one machine, setting them in the next, then pressing a cycle start button. If the person is only moving one piece at a time between machines, he or she has an extra hand free, and the process is wasting human operator potential. Moreover, the X10 team made a terrible mistake in terms of machine capacity. The machine they had purchased could make several pistons at a time, and the final product actually required four pieces, but they insisted on one-piece flow. (See the waste reduction model in Figure 5-1, Chapter 5.) The core philosophy is to reduce waste. Flow is a method used to surface problems, and single-piece flow is not always the best choice. In this case it added to waste.
4. Don’t settle for elaborate technical quality solutions when you can build in quality. Jidoka, or endowing a process with the human characteristic of being able to determine a quality product has been created, is a Toyota Production System term that the X10 and A1 teams took quite differently. It appears that the data collection pack- age the X10 group was considering would be used to make sure that no bad parts were passed on to the next process, an admirable goal. However, the system was geared toward uncovering defects, not preventing their creation altogether. This is an example of automating data collection rather than finding the root cause of a problem and quickly countermeasuring it. In comparison, the A1 line was designed to produce fewer defects, simply based on the physi- cal machining characteristics and the process it operated within. The performance indicators of each line demonstrate that designing the process to reduce the production of bad parts from the outset vastly outweighs the results of simply catching errors that an inferior system creates.