The fine line of effective 5S in lean manufacturing

This punch rack, clearly organized and continually improved upon, is from a fabricator that has sustained 5S for more than a decade.

Sort, set in order, shine, standardize, and sustain. The elements of 5S sound so logical, so simple. Why wouldn’t any fabricator work to sustain such a system? Yet it’s not unusual for a 5S program to break down, especially in the highly variable world of the metal fabrication job shop that processes one unique job after another.

Why do shops work through the first four S’s but then fail on the fifth? Why can’t 5S be sustained? To uncover one perspective, The FABRICATOR spoke with Tony Manos, founder of 5S Supply, Flossmoor, Ill., whose business focuses on the 5S process, and Profero Inc., a consultancy based in Frankfort, Ill.

Of course, when asked why 5S fails, Manos gave the expected answer: lack of management buy-in and support. “[Company leaders] need to be actively involved and give people the time and tools they need to succeed.”

He then paused briefly. “Yeah, I know. Everyone says that.”

Manos added that it’s said all the time because it’s true, of course; the key is dissecting the nuts and bolts of “leadership support” to make sustaining 5S a reality. How does a fabricator do this? As Manos described, it requires finding the optimal balance, a Goldilocks zone between insufficient and excessive levels of management.

Insufficient Management

The moment Manos walks into a facility, he sees signs of insufficient 5S management almost immediately. The signs are pretty obvious: a shadow board with most of its tools missing next to a workbench with various tools strewn about; a drawer full of punches and Allen wrenches everywhere, with nothing clearly labeled. Some of this might have to do with a lack of hands-on management, especially when dealing with employees who call themselves “naturally messy.”

“This can be difficult, especially when you have a great operator,” Manos said. “And the person might be extremely productive. But ask yourself, ‘When you hire someone, would you want to hire someone who’s messy or someone who’s neat?’ Yes, you might have messy people who are productive, but you also have productive people who are neat. And if you had a choice of hiring one, you’d probably go with the neat person.”

This has to do with a person’s ability to work in a team. An employee with an extraordinarily messy workstation or desk might be productive, but what if an emergency arises and he or she can’t come to work for the next day or week? A messy workstation might be familiar to the owner but a chaotic mystery to the substitute who needs to keep work flowing in the person’s absence.

Insufficient management can involve a simple lack of oversight, but Manos cautioned that 5S shouldn’t be forced down people’s throats, either. More often than not, a lack of oversight really isn’t the problem. The issue really stems from a lack of structure that allows for efficient work flow.

Knowing How Work Flows

Many job shops use 5S to dip their toes into the lean manufacturing pool. After all, not all lean tools work in the job shop, but 5S is pretty universal, so why not start there?

Manos agrees that 5S is a good start, but the challenge is that if overall part flow is highly variable, bordering on chaotic, a workstation that’s undergone 5S might be insufficient to control the chaos.

Imagine an assembly station designed to handle every part requiring assembly in the entire fab shop. The workpiece size, the variety of tools, assembly ergonomics, and more all change multiple times over a shift. Because operators have to manage so many tools, they find it difficult to keep tools orderly. Designing such a workstation for maximum efficiency is a tall order, if not outright impossible, because it’s so difficult to predict which tools an operator will need at what times.

Hence, during the shift, operators scurry about their workstations, reaching for one tool in one area and another tool in a faraway area on the other side of the workbench. One operator needs an unusual tool that’s in a central tool crib. So he walks there and finds a shadow board with space for the tool—yet no tool, and no record of who took that tool. So the frantic hunt begins, the assembler gets behind, and he forgets about putting tools back where they go. And why bother? He has to manage so many tools, trying to keep things neat just slows him down.

“This is where value stream mapping comes into play, as well as the process-family matrix, which can even help job shops understand a lot about how jobs actually flow,” Manos said. “Many say that everything the shop makes is absolutely different. But quite often it’s not as different as you think. There’s usually a way to group similar jobs together.”

In custom fabrication, many parts flow through a similar routing: laser cutting or punching, flat-part deburring, welding, and grinding, with hardware insertion interspersed between depending on the part geometry or job requirements. A part might require brakes with different bed lengths, tools, or tonnage; thicker parts might require a higher-wattage laser. But many of the routing patterns are clear, and from that can emerge new ways to flow product through the plant.

Better Flow, More 5S Opportunities

Manos added that new flow patterns should create routings dedicated for certain “repeater” jobs or product families—perhaps only 30 or 40 percent of the total work. But from a 5S perspective, dividing the work flow helps simplify the 5S process. No longer does a certain workstation require every tool under the sun. Reduce the number of tools required, the easier it is to define commonly used tools, and the more tools can be dedicated to specific workstations—no time lost walking to a tool crib.

Fewer tools also means more resources can be spent on presenting those tools to assemblers and operators to make their jobs easier. Manos described workstations in a high-product-mix assembly line that, among less used tools, had four common tools that were suspended overhead with spring-loaded load balancers.

“Yes, each load balancer cost a few hundred dollars,” Manos said, “but weigh that against all the time the operators spent previously looking for tools. Now, when they need the tool, they reach up and pull it down. When they’re finished, the tools float back up above the workstation.”

Minimizing the part flow variation also opens up more organizational possibilities. Manos described one job shop with a repeating job that flowed to a dedicated assembly cell. The job incorporated hundreds of different product variants, so many that it was impossible to design an assembly cell with all the tools for every part. So in this case, kits of workpieces were delivered alongside a tray full of the tools required for assembly.

Organizing flow reduces variability at the workstation, which makes it easier to organize, clean up, and perfect over time. Manos talked of using color and symbols wherever possible. For instance, tools for a specific shadow board can have a tape or elastic band of a specific color that matches the color of the board, so that everyone knows which exact tool—be it a mallet, hammer, micrometer, or anything else—goes with which shadow board.

Stocking bins for hardware can have a specific color and a picture of the hardware that should be inside, accompanied by the actual name of the hardware in the bin. Text backup should always be there for the color-blind and for different items that look similar, like similarly sized hardware with different threads.

Excessive Management

Manos stressed that these and other visual communication tools can work great, but they have to make life easier for the people who use them.

“Some tend to make things much more complex than they need to be,” Manos said.

Complex color-coding is a prime example. Most who have worked in manufacturing know the significance of yellow lines on the floor showing traffic lanes, workcells, and paths to an exit. “But I walked into this one plant, and I looked at the floor, and I also saw light gray and dark gray lines. I asked what those meant, and they told me, ‘Well, light gray is for where you can walk and the dark gray is where work is being done.’ I then asked, ‘Can’t you just put the yellow lines there?’”

This is one example Manos described to illustrate an excessive level of 5S management. The same thing goes for excessively complicated color-coding schemes, labels, and tracking systems. In fact, excessively complicated 5S schemes and tracking systems often act as a Band-Aid for a deeper consistency problem in preproduction or production.

Consider the industry’s push toward a paperless shop floor. Say the shop wants to go paperless because it takes forever to assemble all the paperwork into a traveler. Then the seemingly inevitable happens; the customer has a last-minute change, so office personnel rush to the floor with new instructions and revisions, praying the operator hasn’t started the job yet.

Manos said that in many cases, going paperless can add tremendous value, particularly if the markets a job shop serves demand traceability or customer orders change midstream. But shop managers also should look at the big picture. If customers change orders at the last minute, could some mechanism in preproduction catch those changes before the order is released?

“Similarly, if customers are calling to check on orders, why are they calling?” Manos asked. “And sure, it’s nice to pull up a job with a few clicks, but you know how else you can check up on a job? You can go to gemba. You can go to the shop floor and look for yourself.” And if it takes forever to find a job on the floor, perhaps the floor has too much WIP, and a bottleneck or other problem related to work flow needs to be addressed.

Manos emphasized that even after asking these questions, going paperless might still be the way to go. It depends on the company’s needs and the markets it serves, but it also should depend on what makes life simpler and easier for front-line operators.

The less complicated and clearer the important information is—that is, the information that tells someone what to do next and how—the more efficient an operator at a workstation can be, which has a direct impact on how 5S is maintained. This might entail a simple, color-coded job packet, always placed in an outlined area on a shadow board. Or it might include scanning a bar code and using a laptop or tablet to access the job information.

But what if an operator has to scan multiple items at various stages of fabrication or assembly? “In this case, what value does this add?” Manos asked, adding that it might add value if customers require traceability or if measuring certain processes is instrumental to make things more efficient. But to avoid waste, it’s at least always worth asking the question.

Manos described another example of a shop where information for the job packets for a specific assembly was reorganized by someone in the front office. “That person decided to organize all the folders in the computer system alphabetically. But then we asked the operators how they would organize the information, and they told us that organizing by customer name worked best for them.”

This brings up what Manos said is a telltale sign a 5S program is being overmanaged: No one bothered to ask front-line personnel what would work best for them.

Audit Strategies

He added, though, that 5S should be a collaborative effort involving not just front-line people in one department, but people across and at all levels of an organization. It’s why the best 5S audit procedures regularly involve people from other areas of the business who can look at a workspace with fresh eyes.

For instance, someone in welding might look at punch tool organization in the cutting department. Each upper and lower tool has its place in a drawer interior complete with foam cutouts, making it impossible for someone to return a punch tool to the wrong place. The welder would appreciate this, but he also might consider the tool labeling to be a bit cryptic. Would they be understandable to someone new to the punch department? Is there an easy way to make the labels clearer without making things less efficient for those who don’t need the clarification? Perhaps so or perhaps not, but because someone from another department is conducting the 5S audit, the question is at least being asked.

Related to those audits, the wrong incentives can create problems and lead to 5S’s eventual demise. Manos visited one company where supervisors’ performance reviews hinged partly on the state of 5S in their departments. “I remember seeing an audit result showing 85 percent, and I saw the workstation,” Manos said. “There was no way that workstation should have gotten that audit score. So then we dug a little deeper, and we found that the supervisor gave those scores because he didn’t want to look bad.”

As Manos explained, making 5S part of performance reviews isn’t a bad thing at all. But basing them on the score alone pulls the focus away from what really matters: improvement. “I told them, ‘Let’s focus on improvement versus just the score.’” In many ways, it’s the change in score, and not the score itself, that really matters.

Of course, scores shouldn’t be all over the map either. If they are, the audit process becomes less useful, giving 5S a better chance of failure. True, some elements of a workstation can be counted and measured, but some aspects of 5S are inherently subjective.

Here is where “auditor calibration” comes into play. “For this, we identify the auditors, give them a sheet, having them conduct the audit on their own, judging the same workstations, then we come back and talk about the results and see what the variations are. We ask them why they scored the way they did.”

During these meetings, the auditors develop scoring standards. Like calibrating a gauge for use across the shop floor, “calibrating” auditors minimizes the variation and makes the audit more meaningful and useful.

Being Useful

Manos recalled one shop with a lighthearted front-office employee. On his desk was a stapler, and to it he had glued a flat piece of painted wood with a black outline and a label that read “STAPLER.” Wherever that stapler was, it would be labeled and in its “place.” A sense of humor is never a bad thing.

The joke’s double meaning illustrates the fine line managers walk when sustaining 5S. A 5S program represents change and can be seen as jarring and somewhat silly and excessive. Why have a label and outline around a stapler? That’s ridiculous.

Well, it might not be ridiculous if people spend a lot of time looking for a particular stapler. And if that wasted effort leads to a rushed office employee making a mistake in order preparation, it could snowball into a huge problem on the shop floor.

“Sustainable 5S is about finding balance between under-control and over-control,” Manos said.

Find that fine line between over-control and under-control, between insufficient management and micromanagement, and all five S’s, including “sustain,” can thrive.