Companies decide to use the skills of outside consultants for a number of reasons. Below is a list of the most common questions asked by those just beginning their Lean journey.

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1. What is the difference between the Toyota Production System (TPS) and Lean Manufacturing?

2. How do I get the most out of a lean benchmarking trip?

3. What is the Toyota Production System (TPS) house?

4. What are the seven wastes?

5. Will I be kaizen-ed out of a job?

6. Does single minute exchange of dies (SMED) really mean set-up times of one minute?

7. I am told that value stream maps must be completed by hand only. Does this mean I can not purchase value steam mapping software?

1. What is the difference between the Toyota Production System and Lean Manufacturing?
The Toyota Production System (TPS) was developed by the Toyota Motor Company after the Second World War. Many individuals contributed to the development of this manufacturing philosophy, aimed at eliminating waste from all business processes.

Two well-known individuals behind TPS were Taichi Ohno, a Toyota employee who is often called the father of TPS, and Shigeo Shingo, a Toyota consultant who was the founder of the Institute of Management Improvement in Japan.

In the 1980’s as western executives began taking note of Toyota’s success, academia also begun studying and writing about the benefits of this seemingly revolutionary production system. Two of these academics were James P. Womack of the Massachusetts Institute of Technology and Daniel T. Jones of the University of Cardiff in Wales. It is these authors who are widely credited for coining the term “lean manufacturing” to describe the Toyota Production System to westerns.

So in essence, the terms "Toyota Production System" and "Lean Manufacturing" mean the same thing and can be used interchangeably.

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2. How do I get the most out of a benchmarking trip?
The experienced lean professional can spot lean companies after just a few minutes on the shop floor. This individual will evaluate a production environment not by the words that the guide says, but rather with his eyes as he observes how work is flowing between processes. While this may take some time, with experience anybody can develop the ability to see and eventually learn in lean environments.

Below we have developed a basic checklist of some important items to look for when participating on a benchmarking trip. While the bullets are certainly not all inclusive, they are a good starting point to begin examining the intricacies of a lean environment.

A Useful Benchmarking Checklist:

Upon entering the production area, can you see how production flows within the factory? Is it intuitive? How does product get from raw materials to finished goods? Generally, the harder it is to see how material flows, the more waste is occurring during the production process.

1. Does the location have a plant-wide current and future state value stream map? Do team members know where it is? When was the last time the map was updated?
2. Do team members measure their performance (quality, cost, safety, delivery and morale)? Are problems identified on these metrics brought out in the open (i.e. can you see them) so that they can be corrected?
3. Does the plant work towards a takt time?
4. Can you spot standard work within arms reach of each team member? If you can inspect a copy, do you understand the instructions? Could you perform the work?
5. How many continuous improvement (kaizen) activities are taking place? Is the kaizen culture obvious?
6. How are production problems communicated? Is there a clear escalation process if the line stops?
7. How much knowledge do individual operators have about the Toyota Production System?
8. What is the trigger to 1) send raw material to the line and 2) produce and move WIP?
9. How is pitch set? Are pitch lines flexible?

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3. What is the Toyota Production System (TPS) house?
One of the first items covered by the lean student is a well-known illustration of the Toyota Production System, also called the TPS House. The TPS House was originally developed by Toyota to graphically and easily explain the fundamentals of the Toyota Production System to outside suppliers.

The underlying premise of the illustration is the ultimate goal of eliminating waste from the shop floor and the office environment. This waste disguises itself in three forms: (1) unevenness, (2) unreasonableness and (3) wasteful activates.

To best understand the TPS house, we need to analyze it from bottom to top, just the way a house is built. When constructing a new home, one first needs to build a strong foundation. Next, one builds strong walls, or pillars as Toyota calls them. These pillars must be strong, otherwise our building will crumble when confronted by a destructive force. Next, we need a roof; there is no point building a house if we do not put a roof on it to protect us. Finally, once the house is built, we need to create a comfortable environment inside the structure so that the inhabitants can live in harmony.

While this may sound a little far fetched if you are hearing about it for the first time, the illustration is a core element of Toyota's success. Contact us if you would like to ask us any questions or request a complimentary presentation explaining the details of the TPS house.

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4. What are the seven wastes?
For several years beginning after the Second World War, Taichi Ohno and Eiji Toyoda studied and eventually developed a deep understanding of the wastes that occur on a shop floor. After years of effort, seven categories were identified:

1. Labor
2. Overproduction
3. Space
4. Defects
5. Unnecessary human motion
6. Inventory
7. Transportation

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5. Will I be kaizen-ed out of a job?
The single most common fear that operators have when learning about kaizen and waste elimination is that they will loose their job after a kaizen event. After all, isn’t labor the first waste listed (see preceding question).

On the surface, this concern seems to be valid. After all, if we are trying to reduce the waste in an operators work content (labor), is it not conceivable that eventually we will eliminate enough waste to reduce an entire person?

This is absolutely true. In fact, when following the kaizen mindset, headcount reduction could happen within week! However, we must not confuse elimination of work with the subsequent elimination of headcount.

In other words, if an operators work is eliminated, it does not mean that their job has to go with it. Instead, these individuals can be redeployed to other areas of the company… in identifying more waste for example. Of course, as attrition occurs (voluntary departures, retirements, etc…), it is perfectly acceptable not to rehire the position.

Consider this: eliminating waste through kaizen is performed by everyone in the company, including individual operators. If a company chooses to reduce headcount as soon as a person’s job is eliminated, it is quite possible that the zeal for additional kaizen will not be felt by the remaining workforce.

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6. Does Single-Minute-Exchange of dies (SMED) really mean set-up times of one minute?
No, even Toyota can not change all of its stamping tools in under a minute. Instead, we can think of SMED as single “digit” minute exchange of dies. That is, Toyota aims to have set-up times under 9 minutes and 59 seconds. (The minute hand is still a single digit!) To their credit, Toyota achieved this over 20 years ago.

Having said this, we must remember that the right SMED number is a function of takt time, model mix and available equipment. Generally, the lower the takt time the greater the need for a very short changeover time. In the absence of low changeover times, more equipment and money will be needed to ensure continuous supply of WIP.

SMED history: It took Shigeo Shingo almost 20 years to develop the SMED system. First at Mitsubishi Heavy Industries in the 1950's and later at Toyota Motor Co. in 1969, Mr. Shingo taught the world how to reduce set-up times first by 75%, later by 95% and finally by 99%. While technology and innovation has enabled businesses to build upon his success, Mr. Shingo’s methods are still considered the benchmark of SMED today.

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7. I am told that value stream maps must be completed by hand only. Does this mean I can’t purchase value steam map software?
A value steam map is a paper-and-pencil representation of material and information flow for every step of a particular process. Value stream maps can be thought of as the blueprints for transforming traditional companies into lean enterprises.

There are clearly undisputable benefits in favor of completing a value stream map by hand. This is because as the map is being completed, one inevitably discovers more detail about the process being studied. This discovery requires frequent erasing and redrawing of information to show what is actually going on.

This revision makes it quite impractical to complete value stream maps with a computer. Also, since they must be recorded at the place of work (on the Gemba) it makes it quite impractical to use a computer.

A case for software
Once accurately recorded, the value stream map needs to be communicated with others. At this point, it often becomes impractical to run around with a drawing in pencil. This is where the argument for value stream map software comes in. There is certainly nothing wrong with purchasing software in this case. However, creating a PDF document is just as easy and much less expensive.

Bottom line
Our opinion is that as long as the value stream map is first recorded by hand on the shop floor, subsequent copies may be completed with software.