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August 3, 1998

9 Min Read
By Design: What image problems?

In this bimonthly column, Glenn Beall of Glenn Beall Plastics Ltd., Libertyville, IL, shares his special perspective on issues important to design engineers and the moulding industry.

Most injection molders are too busy to be concerned with plastics' image. Why should they be? The growth of the industry proves that plastics' reputation among consumers must be good. But appearances can be deceptive. According to the most recent American Plastics Council polling, plastics' image may not be as good as it appears. Among those surveyed, people who harbor an unfavorable opinion of plastic materials and the industry increased from 22 to 27 percent. A 5 percent increase between 1996 and 1997 may not sound like much. But if that trend continues for another five years, more than half of the consuming public will not view plastic favorably.

The public's main concern seems to be with such issues as health, safety, and the industry's lack of commitment to environmental issues. These concerns are understandable, considering Greenpeace's continuing attacks on the use of PVC in toys, medical devices, and just about everything else. The rate of recycling of plastic packaging is now declining and the major plastic material manufacturers have shut down their recycling operations.

Industry insiders who understand the benefits of plastic materials find it hard to accept the fact that more than one fourth of the population views plastics in a negative light. Yet anyone old enough to remember the second World War already knows that plastic materials have always had a less than sterling image.

Plastics helped win that war by standing in for steel, aluminum, and rubber, which were in short supply. Plastics were rewarded for their wartime service, not with the Distinguished Service Medal, but with the title of the "Substitute Material." Immediately following that conflict, there was a stampede to fill the pent-up demand for consumer products. The plastics industry benefited, but some greedy OEMs and their molder suppliers produced a lot of shabby products. Many customers were justifiably disappointed with the performance of these early plastic products, but the plastics industry prospered. The industry's success in spite of this in your face attitude could be traced to plastics' low cost and design freedom. As peacetime products, plastics became known as cheap, imitation, substitute materials. The industry has never shaken that image.

Echoes from the Past

In 1979, 34 years after the end of WWII, Sid Gross, the editor of Modern Plastics magazine, commented on the negative perception of plastic products. The following excerpts are of interest: "Despite the persistence of the bad image, plastics sales over the past 26 years have run at above 27 percent per year compounded, a growth rate that exceeds that of all other growth materials of design and construction, no matter how good their image. How is that possible? The reason is obvious: once the industry had dealt with its design, property, and performance problems, plastics became the obvious materials of choice in so many applications that manufacturers (who live by ROI and not image) flocked to it in ever-increasing numbers."

One of Gross's comments bears repeating, in light of current conditions: "Once the industry had dealt with its design, property, and performance problems, plastics became the obvious material of choice."

The overall properties of plastic materials have continued to improve since Gross wrote that article 19 years ago. Regrettably, the same cannot be said for the design and performance of plastic products. Today, there are absolutely fantastic, high-performance plastic products being introduced into the marketplace. At the same time, there is an increasing number of plastic products whose performance is declining. Many of these products are not being properly designed for a specified material and process. This is hard to rationalize, considering all of the new design tools and everything that is now known about product design.

Plastics' Image Tarnished

In more recent times, plastic materials' improving image was tarnished by the competitive material industry's success in falsely portraying plastics as the main culprit responsible for the world's solid waste problems. Grade school teachers started teaching their students that hamburgers packed in expanded polystyrene clamshell boxes were destroying the ozone layer and Bambi's habitat. Amidst a barrage of publicity, McDonald's stopped using those packages in 1990.

The plastics industry has now fallen into the clutches of the bean counters. OEMs vaguely remember Demming, and they talk quality while worshipping cost. Cost reductions are now being pushed so far that performance is beginning to suffer.

Guilt by Association

A 1995 class action suit revealed poorly designed plumbing fittings that cracked and plastic pipe that failed. The settlement in that case was $950 million. In a new action, a consortium of 27 furnace, boiler, and pipe manufacturers have put up $100 million to replace plastic flue-vent pipes that crack and leak carbon monoxide. Many of the failures in these two cases can be blamed on improper installation. In spite of that fact, if the failed part is made of plastic, the plastic material is also blamed. It is easy to understand how the people who had these plastic parts in their homes no longer view plastics as a wonder material.

The consuming public does not know the difference, but anyone who does know anything about plastic materials would have preferred that all of the interior trim parts in automobiles had not been changed from ABS to polypropylene (PP). PP is thought of as a low-cost, large-volume commodity plastic material. With the addition of talc and glass fibers, PP became an engineering material that became the poor man's nylon. PP is a wonderful, versatile plastic material, but its performance characteristics are not as good as ABS.

The use of PP in this application is justified as being "good enough" and, after all, the consuming public does not know the difference. The conversion from ABS to PP was a significant cost reduction. Coupled with 1000 other similar reductions, the cost of the average automobile should have come down, but it went up. The Detroit Big Three are now wallowing in profits, while their suppliers shudder, waiting for the next round of cuts.

Who Pays for Quality?

During the February 1998 Society of Automotive Engineers Conference, a survey revealed that cost reduction is still the biggest issue facing automotive design engineers. Thirty-nine percent cited cutting cost as their foremost challenge. Quality concerns ranked sixth, at only 6.5 percent. It is revealing to note that low cost (29 percent) and quality/reliability (24 percent) ranked first and second among the things automakers wanted from their suppliers. In other words, the importance of quality changes depending on who is paying for it. This sort of casts the car companies in the same mold as the greedy old OEMs who stuck plastic with its poor image back in the 1940s.

The situation is not limited to automobiles. The same thing is happening in all segments of the market. It is generally agreed that the thermosetting polyurethanes produce the highest quality sporting shoe soles. Most of the shoes being offered for sale are made of a lower-cost thermoplastic elastomer (TPE). Once again, the TPEs are "good enough" and the customer does not know the difference until after the product is purchased.

The same thing could be said about plastic automobile bumpers and body panels. Consumers can't tell the difference between the various types of plastics, but they do become aware of whether or not the product performs as anticipated or claimed. In the 1980s, consumers drifted away from garments made of synthetic fibers. Cotton and wool became the materials of choice. That segment of the plastics industry is just now recovering. If the industry continues to downgrade at the present rate, the image of all plastic products will continue to suffer accordingly, and with justification.

Quality by Design

Sid Gross also referred to the poor design of early plastic products. Today, design engineers are more creative in their use of plastic materials than ever before. It takes only a walk through the local car lot or shopping mall to be impressed with the feature-laden products that designers have created with plastic materials. Only the trained eye of the molder sees the shadowy sink mark, the weld line, the warpage induced "gaposis," and the sharp parting line on the handle. At the mall and elsewhere, people can be observed carrying their most valuable possession in an infant seat with a snap-fitted handle molded in a low-cost commodity plastic material.

It is safe to conclude that the design of plastic products has definitely improved since the 1940s. Regrettably, the CAD-generated visible outer surfaces of these beautiful products often hide a multitude of part design defects. Cutting cost by downgrading to a lower-cost plastic material requires not less, but more attention to design details. ABS might be strong enough even with a sharp corner, but PP requires a radius. Today, the standard excuse for this lack of attention to design details is that the product has to be on the market as soon as possible. Given that situation, there is not enough time to worry about the details.

What's a Molder to Do?

It is very difficult for a molder to convince a customer to upgrade to a higher-cost, better-quality plastic material. A custom molder can, however, suggest design changes that will improve cost and quality. Not all OEMs are receptive to suggestions that require the time necessary for redesign. Yet the trend is for OEMs to rely more and more on their suppliers. One way to circumvent this objection is for the molder to do the redesign for the OEM. This approach minimizes the time and effort required by the OEM.

This lack of attention to design details has now been prevalent for so long that it must be concluded that design engineers are not suddenly going to start doing a better job of designing plastic parts. In many cases, the CAD operators who are now designing injection molded parts are unaware of the importance of a uniform wall thickness, draft angles, and corner radii. If the designers don't know any better or are not going to take the time to worry about the details, then the molder is the only one who is in a position to make the necessary improvements.

As the economy progresses into its eighth year of continued growth, it is tempting to believe that these good times will continue forever, but such continued growth is unlikely. Of course, all injection molders want the plastics industry to continue its recent pattern of growth. But this growth can only continue so long as consumers have a good impression of plastics and continue to purchase plastic products. In order for this to happen, everyone in the industry is going to have to take the time to worry about plastics' declining image and do something to portray plastic as the wonderful material that it actually is.

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