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One of the single most effective projects that I worked on in the past five years was also the simplest; in fact, I proposed this change in my first week of work.

During my interview, the engineering director took me for a walk through the plant.  It was obvious that a lot of changes needed to be made.  He complained, “Every time we have a defect in this cell, we have to scrap the whole lot, 50 pieces.”  I was shocked that a man with a title of “Engineering Director, North America,” could not see the solutions that were right in front of him.  

My initial reaction was to ask a question, “Have you tried reducing your lot size?  Maybe cutting your lots in half?”  His response was even more dumbfounding, “What do you think that would do?” 

So, I went on to describe all of the benefits of Single Piece Flow, and added the obvious fact that if the company requires the entire lot to be scrapped because of one defect, then you would only be scrapping 25 instead of 50 every time that one occurred.  He really got the point once I asked him to think about it on a larger scale, “How many would you have to scrap if you had a lot size of 1,000?”  Of course, he said, “1,000.”

When I got there, the process looked something like this:

There was an obvious disconnect between each process, even though the stations were literally five feet apart.  Each station operated as its own entity, not caring whether or not it was receiving or shipping defective products.  The operators were there simply to put in their time and collect their money.  They cared nothing for the products they were making and took no pride in quality workmanship.  If something failed at one of the inspection stations, then the entire lot was scrapped – big deal – they did whatever someone told them to do for eight hours and that was it – product or no product.

As you can see by looking at the diagram of the process, they had incorporated Inspection stations.  Inspection is a large portion of waste in many manufacturing processes. Sure, it may be necessary in some instances, but the inspection should still be dealt with in-process instead of having it as its own workstation.  

By having Inspection as three entirely separate workstations, defects accumulated lots of 50 waiting in queue and valuable resources were tied up in labor, fixed overhead and much desired floor space.

As a result, I suggested eliminating Inspection from the process.  Well, I should say, I suggested eliminating the wasteful aspects of Inspection.  Because we are dealing with electrical devices that are tested to a standard, the cables must be checked during manufacturing to certify the product as passing the standard, so the Inspection needs to be in there somewhere.

I suggested that we put the inspection testing equipment within the previous station’s area (i.e. the pre-inspection station, e.g. wire insertion, pre-mold, mold), to be checked one at a time as they are made.  The results showed instantly!

• In each of the cases, the inspection operator was eliminated and added to other cells for more value added work.  
• Each of the pre-inspection stations would make one unit and test it instantly.  If there was a problem, it was solved immediately and no other cables would be tainted by the same issue.
• Additionally, in all cases, the inspection portion of the manufacturing could be done (by the testing apparatus) while the operator was preparing the next sample.  

At this point, we also rearranged the cell so that it was in the classic ‘U’ shape which cut the travel distance by 100’.  It had been segmented into two lines, with two operations being 110’ apart from another, this was shortened to 10’.

The bottleneck of the entire line was the Pre-Mold operation which was considerably slower than the other processes (the Wire Stripping and Crimping operations were very slow also, but each had 3 workstations, as these were inexpensive compared to a molding machine).  This was also the highest offender when it came to quality issues.  At this step, the individual wires were consistently getting snipped by the mold, causing complete electrical failure of the connector.

Before the improvements, it was easy for this process to make upwards of 200 bad cables before the Inspection station got around to discovering their was a problem!Because it was the bottleneck, it was absolutely imperative to always keep the Pre-Mold operation filled with work.  To achieve this, we setup a sequenced pull system that started with a supermarket between the Wire Insertion w/ Inspection operation and the Pre-Mold operation.  To keep the supermarket fed, we introduced FIFO lanes upstream.  The supermarket handled multiple varieties of cables because the Insertion operation was the first step in the system where product variety appeared.

In the operations upstream from there we used FIFO lanes because the product mix was entirely the same.  Each was held to a maximum storage amount; the supermarket with 5 and the FIFO lanes with 2.With the addition of the FIFO lanes and the supermarket, we were able to work at the pace of the bottleneck.

Granted we were able to speed up the processing of the bottleneck through a SMED event, which required some machine design from the maintenance department, but it was still the bottleneck regardless. 

Efforts to justify the purchase of another molding machine for that area were just not cost effective. (As part of the SMED, we added a second bottom half to the mold which could be loaded while the current cable was being molded.  After the current one finished, the top half lifted up and the other bottom half slid into place, and the molding continued while the other bottom half was unloaded and reloaded for the next cable.)

Since we were so constrained by the Pre-Mold operation, we were able to use the same operators that ran the operations upstream from Pre-Mold to run the operations on the back end of the system.The results speak for themselves:

• Output of quality products increased from 1.20 units/hour to 5.56 units/hour.
• Quality problems and rework was down by 90%.
• The number of associates went from 14 to 9, allowing those additional 5 people to be moved to areas where they could perform more value added work.
• Associates saw the real effects of their work, taking on more responsibility and having more respect for themselves, the jobs that they perform and the products that they produce.

Over the years I have collected several quotes from various Lean and Six Sigma professionals, historians and trainers.  I have listed most of them below and will continue to expand the list as time goes on.  Enjoy!

“A bad system will defeat a good person every time.” – Deming 

Eliyahu M. Goldratt & Jeff Cox gave us several good quotes related to manufacturing in the book,  The Goal:  Excellence in Manufacturing (later called The Goal:  A Process of Ongoing Improvement).  The book, a work of fiction, leads readers into the concept of the Theory of Constraints through an easy to read novel setting.  These are some famous quotes from The Goal:

“Make the bottlenecks work only on what will contribute to throughput today … not nine months from now. That’s one way to increase capacity at the bottlenecks. The other way you increase bottleneck capacity is to take some of the load off the bottlenecks and give it to non-bottlenecks.” - quote from The Goal

“If we reduce batch sizes by half, we also reduce by half the time it will take to process a batch. That means we reduce queue and wait by half as well. Reduce those by half, and we reduce by about half the total time parts spend in the plant. Reduce the time parts spend in the plant and our total lead time condenses. And with faster turn-around on orders, customers get their orders faster.” - quote from The Goal

“An hour saved at the non-bottleneck is a mirage.” - quote from The Goal

“I say an hour lost at a bottleneck is an hour out of the entire system. I say an hour saved at a non-bottleneck is worthless. Bottlenecks govern both throughput and inventory.”  - quote from The Goal

Again, with any of the lean quotes I present, I try to be as accurate as possible.  If you see any discrepancies, please email me.

Taiichi Ohno (1912 - 1990) was a Toyota executive and one of the chief architects of the Toyota Production System.  He wrote several books about Toyota, most notably Toyota Production System:  Beyond Large-Scale Production and Workplace Management.

These are some famous Taiichi Ohno quotes:

“All we are doing is looking at the time line, from the moment the customer gives us an order to the point when we collect the cash. And we are reducing the time line by reducing the non-value adding wastes.” - Taiichi Ohno

“The only place that work and motion are the same thing is the zoo where people pay to see the animals move around” (not exact phrase) - Taiichi Ohno

“Where there is no Standard there can be no Kaizen” - Taiichi Ohno

“Why not make the work easier and more interesting so that people do not have to sweat?  The Toyota style is not to create results by working hard. It is a system that says there is no limit to people’s creativity.  People don’t go to Toyota to ‘work’ they go there to ‘think’” - Taiichi Ohno

“Costs do not exist to be calculated. Costs exist to be reduced.” - Taiichi Ohno

“The key to the Toyota Way and what makes Toyota stand out is not any of the individual elements…But what is important is having all the elements together as a system. It must be practiced every day in a very consistent manner, not in spurts.” - Taiichi Ohno

“The more inventory a company has, the less likely they will have what they need.” - Taiichi Ohno

“Data is of course important in manufacturing, but I place the greatest emphasis on facts.” - Taiichi Ohno

Again, with any of the lean quotes I present, I try to be as accurate as possible.  If you see any discrepancies, please email me.

Shigeo Shingo (1909 - 1990) was an Industrial Engineer who worked as a consultant with a number of companies before finally being brought in to further develop the Toyota Production System.  His most notable contributions and accomplishments include SMED (quick changeovers), Standard[ized] Work and methods of error-proofing.

These are some of his most famous quotes:

“The most dangerous kind of waste is the waste we do not recognize.” - Shigeo Shingo

“When you buy bananas all you want is the fruit not the skin, but you have to pay for the skin also. It is a waste. And you the customer should not have to pay for the waste.” - Shigeo Shingo

“A relentless barrage of ‘why’s’ is the best way to prepare your mind to pierce the clouded veil of thinking caused by the status quo.  Use it often.” - Shigeo Shingo

“Improvement usually means doing something that we have never done before.” - Shigeo Shingo

“The best approach is to dig out and eliminate problems where they are assumed not to exist.” - Shigeo Shingo

“Are you too busy for improvement? Frequently, I am rebuffed by people who say they are too busy and have no time for such activities. I make it a point to respond by telling people, look, you’ll stop being busy either when you die or when the company goes bankrupt.” - Shigeo Shingo

Again, with any of the lean quotes I present, I try to be as accurate as possible.  If you see any discrepancies, please email me.

“Kanban is like the milkman. Mom didn’t give the milkman a schedule. Mom didn’t use MRP. She simply put the empties on the front steps and the milkman replenished them. That is the essence of a pull system”
- Ernie Smith, Lean Event Facilitator in the Lean Enterprise Forum at the University of Tennessee

Now, this quote was passed on to me in an email about two years ago.  I don’t know if the quoted individual is correct, so if anyone knows otherwise please email me.  I have heard several similar quotes regarding Kanban and the milkman, as well as other metaphors regarding replishment systems.  Regardless, I wish that more people were aware of this reference.

I don’t know Mr. Smith, but I’m sure he’s a good man (I base that off of the fact that he’s spreading the good word of Lean Manufacturing!).  I like the way that this quote brings all readers into understanding through the use of something so natural and simplistic as a reference to one’s mother.  Surely, if your mother could participate in a Lean activity like a self replenishing pull system without even knowing it, then it must work pretty well if it never interrupted her daily schedule and provided for exactly what your family needed!  Now, I know not everyone was raised around their mother, but the simple idea helps bridge the gap between a supposed structured and rigid system imposed by managers to one of simplified flow.

Sometimes, people new to supermarkets, kanban, and pull system really have a hard time getting it.  They think that you can plug and play supermarkets filled with nice stacks of kanban cards and everything will simply work because you designated an area for it.  In regards to this quote, I’ve seen several cases where a supermarket has been setup and the operations around it just pull and make whatever the MRP is telling them to do.  Again, supervisors and managers want to make it look like things are always running at 100%.  I want nothing less than 100%! I hear that way too often.  That’s why it requires a complete effort from all within the company, but back to the quote.

A good portion of the time, a company will not have the luxury of producing only 3 or 4 types of products.  Usually, you’re looking at figures that are closer to 10, 50, 100 or even 1000’s of different products; all that need to be scheduled and made at different times, in different amounts, throughout the year.  This is where it gets interesting and you need to do some math.

You probably wouldn’t be resorting to the use of a supermarket if you could establish Continuous Flow in the first place.  So, now after you’ve relayed all of your equipment into cells based on the results from your recently done Product Family Matrix, you’re running the numbers to see what your least common denominators are.  Usually (going on basic assumptions) as you go upstream in your process you will see fewer and fewer variations of WIP that will later be transformed into an array of possible product configurations.  Well, it’d be nice to have each of these stored in a supermarket so that you could just pull what you need and then replace it, but most likely, it won’t be that smooth.

In most of the companies I’ve worked in, there have been so many product possibilities that I’ve had to go with the good old 80/20 rule and ended up with a small amount of supermarketed items that in the end will make most of my products.  The 80 stands for 80% of your total production, and the 20 stands for 20% of your total product count.  Clarifying that, it means that 80% of your production can be accounted for by 20% of your products.  A very simple example of this:  You make 5 products in your bread making cell - White, Wheat, Rye, Whole Grain, & Pumpernickel.  For every 20 that you sell, it breaks down like this:

• White:  16 (accounts for 80% of sales)
• Wheat:  1 (5%)
• Rye:  1 (5%)
• Whole Grain:  1 (5%)
• Pumpernickel:  1 (5%)

So, in this very simple model, you’d use a pull system on White bread because you consistently require it based on customer demand.  Think of that scenario, but blown across 1000’s of products.  Instead of one item in your supermarket, how many would you have?  5? 10?  Figuring that out is simple enough, it is getting it to work that is the hard part.

MRP, Master Schedulers, Planners, etc. - they can all screw it up just by doing their job.  They have to be involved and MRP systems need to be adjusted, either through a built in function to work within such systems or manually, if no such feature exists in your current software.  It’s one thing to instruct someone to not make a product because there is already a supermarket full of it across the aisle, but it’s another thing to get them to actually practice it.  Supermarkets, kanbans, pull systems, whatever name your company uses, act independently from supervisors, planners and MRP. 

Kanban the Milkman makes the rounds, quietly moving product into empty spaces left by products used only minutes before; making and replenishing his whole way back to the most basic raw materials.  He’s good and if you just let him do his job - you’ll be all the better for it!!