A WAR STORY: TOILET ROLLS AND SHRINK WRAP
Early in my career I worked as an industrial consultant and I found myself one morning standing in the middle of a large tissue paper mill. Behind me were several tissue machines: huge, noisy, hot things towering into the distance. They made giant rolls of tissue paper, taller than a person standing and much wider. In front of me were converting lines: They took these giant rolls and turned them into toilet rolls.
The converting process has been around for a long time, and consists of taking the giant rolls from the tissue machines and “rewinding” them onto a thin cardboard tube. These are then chopped up into individual toilet rolls by a large scary saw. If they’re fancy rolls, they’re individually wrapped in paper and sealed into a bag or case to be shipped out. If they are a low-cost product, many of them are put straight into a plastic bag as you might see in the grocery store. The whole process is fascinating, and it is well worth watching a video of it online.
In front of me that morning was a converting line that made high-end, branded toilet rolls in a nice fancy wrapper. They were being sold in plastic shrink-wrapped packaging for sale in bulk. I was looking at this line because there was a big problem with it: For some reason the plant could not make enough. You would think that toilet paper would be a fairly boring industry: steady demand, not much action. Well it turns out, as is often the case with these things, that when you look a little closer you’ll find that a lot is going on.
The big drama was that marketing and sales had done a phenomenal job launching a new packaging format. Instead of selling toilet paper in packs of one, four, or 12, they had made a 20-pack. It was flying off the shelves and consumers loved the product. But the mill could not keep up with consumer demand. There were production problems that were spoiling the party, and the marketing dollars were already spent. That was why I was there. Business people hate missed sales.
The main problem on the line was the shrink-wrapper that took the stack of 20 rolls, put plastic around it, and then shrunk it all in a heat tunnel, creating a nice tight plastic wrap. If you wanted to make more you had to speed up the machine—that much was clear. But it was also clear to everyone that it simply wasn’t possible to run this machine any faster. When you sped it up, anything you gained in speed was completely lost, because the machine kept malfunctioning. A pile of loose rolls would fly out of the machine with a bunch jumbled up in the shriveled plastic. Sometimes this would jam the line, and everything would need to be shut down as operators cleaned it up.
This was a well-known problem to the plant and everyone had worked on it. The shrink-wrapper supplier reps had come and gone, leaving a proposal for buying a new, improved machine. The maintenance guys had tried a number of things. The plant engineers had all tried to fix it, as well as the production team. The prevailing theory was that a mechanical arm that drew the plastic film over the stacked toilet rolls could not move faster. There was a strong consensus that nothing could be done and they would just have to continue to work hard through the weekends until demand dropped off, supplying as many 20-packs as possible.
The option to buy and install a new shrink-wrapping machine was seriously considered as a medium-term solution, but that would take a while to plan and then would involve moving a lot of equipment to get it in. The shrink-wrapper was, after all, trapped in the middle of all these converting lines with conveyors all over the place rushing toilet rolls here and there. No one wanted to lose a couple of weeks’ production trying to get that to work. People were out of other useful ideas, and pretty demoralized. This is the sad state that most hard problems end up when people have gone through their list of guesses and failed to solve them.
People are conditioned to guess, and it takes training and skill that comes through guided practice to go beyond guessing. Above all, it requires a certain behavioral attitude that you will learn in this book. People are often reluctant to bring in outsiders, but they also hate weekly conference calls where they are asked why performance is not good enough. So I had an opportunity to take a shot at the problem.
The smart, knowledgeable people who had worked on the issue so far had been trained in a number of problem-solving approaches that relied on experience or guesswork, or sometimes both together. I had been trained not to guess, and when one stops guessing, real problem-solving begins.
I had listened to everyone’s theories and guesses as to what was happening, pushed them out of my mind, and set to work studying the problem. On first pass the solution was not obvious. It was clearly a harder problem. I went into more depth, studied the failures in detail, observed how the process worked, engaged the local team to help me understand key technical points, and wrote out a variable tree (which I’ll cover later) for what must be happening. I spent all morning and most of the afternoon working on the problem, and it felt like the solution was just out of reach, but close.
I methodically eliminated every critical variable except one. Understanding a consistent pattern of tearing, along with Newtonian physics, told me there must be an unintended force acting on the plastic, caused by something snagging the plastic film before it was correctly “shrunk” in the heater section. However, when we cleared out the machine there was nothing that could be in the way and nothing visible when watching the machine run from the side (you could not easily and safely see down the length of the line or from above or below). It was a real head-scratcher.
When I left for the night I reviewed the situation with the night-shift mechanic and asked for his help in figuring out the final part. I had eliminated everything except for this one mysterious force, and we knew that something during wrapping must be catching the plastic in a very specific area of the machine. But I wasn’t yet sure how to observe this mysterious force in action.
I went back to my hotel and pondered the problem at dinner, in bed, at breakfast, and while driving back and towards the facility. When I got in early to catch the night-shift mechanic he came bouncing up to me and handed me a bolt. The problem was solved! We stepped over to a quiet part of the factory floor and he told me the story.
He had been working near the machine the night before when a problem had cropped up. Some errant toilet rolls had jammed part of the machine, so he had fixed it and gotten things running again. He then decided to dry cycle the machine to ensure everything was in alignment before starting production. This involved removing the plastic wrap and stopping the in-feed of toilet rolls.
Then he had a great idea: He decided that this was a good time to “smell the problem.” Previously, we had observed the empty machine while it was off, and we had observed it running, but while it was full of plastic and toilet rolls. He decided to safely, but closely, observe the machine while it was dry cycling, paying close attention to the very specific area we had determined must be the source of the mystery force.
He increased the machine’s speed, above the “DO NOT RUN FASTER THAN” level that every operator had come to accept. Now that he was running the machine empty, he had a clear view of that section, so he shone a flashlight into the machine as he watched.
These machines are pretty noisy and they vibrate a lot, as they have many big moving parts. And as the vibrating got a little more intense with higher speed, he saw something wiggle its way into the chute. Something small, but definitely there. He knelt, bewildered, with this trickle of adrenaline starting to course through him—maybe this was it! It was definitely in the right area, and definitely looked like it could snag the plastic film. But what was it?
He decided to speed up the machine even more and look again: There it was, protruding even further. It was shaking, too. As one more experiment, he gradually slowed the machine down and the thing actually receded its way back into the hole. It became clear that the vibrations of the machine at higher speeds were causing the mystery object to vibrate its way through the hole and poke out into the chute and tear the shrink-wrap.
Resisting the urge to run, he shut down the machine, locked it out, opened up the panel in the general area of the mystery object, and peered inside with the flashlight. And there, sitting in a horizontal hole, was a loose bolt, perhaps mistakenly dropped in by routine maintenance years ago. He almost couldn’t believe it was so simple.
He took the bolt out, closed the machine up, dry-cycled it again to check, and saw this time that no mystery object poked out into the chute. They were ready to rock. He brought the production supervisor over and together they tested out running the machine—with product this time—at full speed, and had hours of great production.
In the following months, their output was up over 25% and they were able to meet customer demand. Weekly production phone calls substituted groaning with high-fives. The success was so invigorating for everyone that the bolt became a symbol of powerful problem-solving.
This was a hard problem because it had resisted many attempts to solve it and been declared unsolvable. It also had a complex pattern of failure for such a seemingly simple issue: The plastic film was not in exactly the same place every time, the bolt did not vibrate and move in the same way every time, and these factors changed with the machine’s speed. Finally, safely observing this was hard and “general observation” would not get you there. I know as I spent time looking at it myself while working out the critical issue, and others had probably spent dozens of hours doing the same.
Solving this problem required core problem-solving behaviors that I had learned, as well as help from the team. To successfully find the bolt, we had to know exactly what we were looking for. I cannot imagine anyone guessing that there might just be a loose bolt vibrating into the way at certain speeds.
What made the difference here? Instead of guessing, we rigorously measured the problem by employing the right problem-solving behaviors. We spent more time “smelling the problem”—understanding the symptoms of the problem itself and rigorously defining it—rather than thinking of causes or solutions. Instead of asking for more ideas or guesses from experts, we dug into the fundamental science behind the problem by exploring the mechanical forces that moved—or tore—the shrink-wrap. We kept our focus by relying only on facts to guide our decisions, and by investigating only the parts of the process that were directly relevant to our problem.
In this book you will learn the behaviors that have solved hard problems like this one. Hundreds and thousands of these problems exist in every business, in society, and in your personal life as well, and they destroy value and progress. They are frustrating and demoralizing. Most of them remain unseen or are hidden as a natural defense mechanism.