Simpler is Better

Sometimes we make things more complicated than they have to be. When we remove the complexity, things seem to get better. I have learned this lesson many times, but my trip to Macon Georgia proved it to me and my team.

In the late 1990’s, I was often asked to help factories solve productivity issues. As I was new to the manufacture of ceiling tiles, I had much to learn. One of my ways to learn was to spend as much time as possible on the factory floor, observing and talking with the operators and mechanics.

I was visiting the largest ceiling plant in the world in Macon Georgia and asked the plant manager if I could spend a day on the line, observing operations and talking with his people. He seemed surprised by my request, but was open to it and gave me the green light.

I started at the beginning of the fabrication line, where the formed 4-foot by 8-foot panels were loaded, and introduced myself to Joe, who was “feeding” the line. He asked me what I was doing there. I explained I was trying to learn how the line operated and the issues he was dealing with. He seemed amused by this and showed me how he operated the line. After about an hour of observation and discussion, Joe had given me a thorough overview of his area of the line and the problems from his perspective. I thanked him for taking the time with me and then left him to go visit with the next operator on the line, Ruth.

Ruth was intrigued by an engineer (a Yankee, no less) who wanted to know what issues she had to deal with as well. She showed me what happened when boards traveled through her paint booth. She was making constant adjustments to the line and I asked her why. She explained the equipment that measured viscosity of the paint was broken, so she was doing her best to get a consistent paint coating, using her experience and observations. Ruth let me try my hand at adjusting viscosity of the paint, and I realized how difficult it was. After some time, I thanked Ruth for her insight and moved on to the remaining operators on the line.

After a full day of visiting, observing, and discussing the issues on the line, I believed I had a plan to make some improvements. I returned to the main office and reviewed my findings with the plant manager. I asked him if he was willing to assemble a small team of operators, mechanics, and a supervisor to work on the problems I had observed. He was extremely willing and said he would have them ready to work with me the next day and for the rest of the week (4 days). Now, I had to determine what to do with my new team.

At 7 am the next morning, I met my team: 3 operators, two mechanics, and a supervisor. We had a meeting room in the middle of the factory. After getting to know each other, I reviewed my observations from the prior day. Luckily for me, two of the operators on the team were Ruth and Joe, so they had some experience with me and felt comfortable talking with me and the rest of the team members. After talking about what I had seen and reviewing their ideas, we came up with two areas to work on: Cutting boards squarely and applying paint consistently. We decided to work on each issue as a full team, one issue at a time. Our first issue was cutting boards squarely.

It’s Hip to be Square

We walked out to the line and went to the equalizer station to see what was going on. The equalizer was a large table saw that cut the 4-foot by 8-foot boards into 2-foot by 4-foot ceiling tiles. The board travels into the equalizer, gets cut into 2-foot by 8-foot strips, then gets transferred at 90 degrees to the next series of saw blades. They then cut the 8-foot strips into 4-foot tiles.

As we watched, we saw the boards go through the saw blades at an angle. Why was this happening? It turns out there were three upper “hold down” rolls driving the boards through the first pass of blades. These rolls were adjustable for on either side of the conveyor. Operators would make pressure adjustments to the rolls to help drive the boards through the saws. There was no way to tell if they were applying equal pressure to the rolls. The unequal pressure on the boards was forcing them through the saws at an angle. Sometimes, this would cause the boards to be cut to the incorrect size, causing scrap.

There were two hold down rolls at the entrance to the saws and one on the exit of the saws. It seemed the two rolls at the entrance were fighting each other, so we decided to raise one of the rolls. To our amazement, the boards ran more squarely through the saws.

Now, we had to figure out how to apply equal pressure to each side of the boards as they entered and exited the saw blades. After many ideas, we realized that by giving the operator the ability to adjust each side of the rolls, they were almost guaranteed to force the boards through with unequal pressure, unless they knew the exact pressure on each side of the board. Since we didn’t have any gauges to measure this, we had to come up with a simpler solution to ensure equal pressure.

Gravity was the solution to our problem. If we could just use the mass of the roll (approximately 55 lbs.) to roll over the board as it entered and exited the saws, the roll would put equal pressure across the board. There was only one way to test this. We disconnected the adjusting screws on the rolls and allowed the rolls to “float” over the board as it traveled below them and into and out of the saws. Now the board was going through in a perfectly square manner. We decided to remove the adjusting screws completely, so operators wouldn’t have the opportunity to reverse this improvement. We also made sure we communicated our changes to all shifts, so people would understand what we did and why we did it. We were proud of ourselves. Now it was time to figure out how we could help the painting process.

It all depends on your point of view

Paint viscosity is critical on a ceiling tile. If the paint is too viscous (too thick), it will cover up the holes on the surface of the tile and reduce its acoustical absorption. If the paint is not viscous enough (too thin), it won’t achieve the proper coverage and required color. The instrument that was broken, a Brookfield viscometer, is a mechanical device that measures the resistance of the liquid as a rod or disc rotates through the liquid. It wasn’t working, so the paint technicians were using a Zahn cup to measure viscosity. This cup looks like a cylindrical ladle with a hole in the center. It is dipped into the liquid and the time it takes for the liquid to totally exit is measured in seconds. The longer the time it takes, the thicker the liquid.

The technicians were taught to observe the bottom of the Zahn cup from the outside. When paint was no longer flowing out of the cup, they recorded the time and then compared it to a chart to assess viscosity. The problem was that as the last bit of paint came out, there were drips, and each operator measured the time differently, leading to variations in viscosity measurements and adjustments. This was leading to problems in the paint booth. We had to find a way to consistently measure the time.

After much trial and error, we realized that we were all looking at the cup incorrectly. If we looked inside the cup, we saw the paint exit in the same way. The moment paint had fully exited the cup, there was a hole that appeared in the center of the cup. Using this method, we were able to consistently measure the time from person to person. It was extremely easy to teach, and we could come up with the ideal time to achieve the desired viscosity. From then on, paint coverage was more consistent from operator to operator.

The team had just solved two major problems and was excited to do more, but these changes took most of the week. We decided to focus the rest of our time on training the other shifts and crews, to ensure they understood and properly utilized the changes.

At the end of the week we showcased our efforts to the plant leadership team. They were impressed with the improvements, enthusiasm, and creativity of the team. These changes led to reduced downtime and scrap for the line. I was invited to the plant many times over the next few years to work with teams using the same approach. I am proud to say that we were able to simplify many other processes and improve performance all over the plant.