In a case of stepchild challenging parent, Nashua Corp. has decided to compete head on against Ricoh, the Japanese firm that makes the copiers Nashua sells around the world.

Starting the first of next year, Nashua intends to manufacture its own copiers.

Anxious over such a risky venture, William Conway, Nashua's president, left this evergreen corner of the globe a few months ago for a beach in Barbados to plan the campaign. He knew it would take money and an all-out push. He figured, too, that the company would need some sort of new philosophy, a purposeful theme, a disciplining force.Something, he thought, having to do with the notion of quality, but he wasn't sure how to make the idea work.

When Conway returned, a call went out for someone who could give Nashua a philosophy and teach it to go against the Japanese. Word soon filtered through company ranks here that a person had been found, a consultant who lives in Washington and is, of all things, a statistician.

It wasn't the first time W. Edwards Deming had been summoned to the scene. In 1949, he had been invited to Japan by the national society of engineers. Their government defeated, their country wasted, their industrial back broken, the Japanese had somehow to restore an economy.

But in view of the circumstances, the subject Deming spoke on-the statistical control of quality-seemed rather arcane.

What did statistics have to do with the problem the Japanese were faced with? Shouldn't they be learning about marketing and finance and all the other corporate strategic skills the Americans had mastered? The Japanese, figuring they could use all the advice they could get, listened anyway as Deming talked.

His lectures then were mostly technical-stuff about standard deviations, variances, control charts and outlyers. But an underlying theme ran throughout, and that was a focus on quality. Deming told the future managers of Japan that if their country was to become an industrial power, it would have to build a reputation of making products that didn't break, conk out or clog up.

The science of statistics, he told them, would help devise industrial systems that make the job easy. Deming had tried to teach the same skills to American managers, but they weren't interested, not then anyway.

In the search for what made modern Japan great, it is tempting to point to Deming and perhaps over-emphasize his role. There were others, of course, who contributed-among them, J.M. Juran, a New York consultant, who like Deming has spent a career lecturing on quality control.

But it was Deming who kicked things off in Japan and today he is a legend in the field. The most prestigious industrial award in Japan, given annually to a company that shows excellence in quality, is named the Deming Prize.

Ricoh, the company Nashua is taking aim against with Deming's help, won the Deming Prize in 1975. The master is now teaching the stepchild the lessons he taught the parent 30 years ago.

The irony of all this was not lost on the small group of executives, office managers and enginers gathered here last week to meet Deming for the first time. About 30 of them had been screened for the session, the only requirement being some basic knowledge of statistics.

Numbers, though, turned out to be almost beside the point. Deming's talk sounded more like a pep rally than a classroom lesson. It began with a simple warning.

"Once in awhile," he said, "I get a letter from someone who wants to install quality control. Quality is not something you install like a new carpet or set of book shelves. You implant it. Quality is something you work at. It is a learning process."

Deming is 78. He has given this talk countless times and delivers it with a practiced flair, like a senior professor before a freshman class. In fact, Deming is a professor-at New York University's business school.

He doesn't, though, think much of the current crop of MBAs being graduated from the nation's business schools. "Of the MBAs coming out this year, there will be thousands who don't understand what we're talking about," Deming told the Nashua group. Management training programs, he said, spend too much time teaching goals and jargon and hardly any time on production techniques.

Deming has a somewhat higher regard for economists and management consultants, but he doesn't consider himself either one. He calls himself a consultant in statistical studies.

At Nashua he asked lots of questions. What is quality? What is it for a shoe, a car, a whole company? How do you measure it? Who's responsible for achieving it? He offered few answers. He was stroking the group, pressing them to think things through. He was setting the table for when he served up his philosophy. that philosophy, interestingly enough, comes out easy on workers and hard on managers. The problem with many businesses, says Deming, has little to do with mistakes by workers and lots to do with a firm's overall production system. It may be designed poorly, ill-equipped or just plain wrongly engineered.

As a rule, Deming estimates that roughly 85 percent of all production errors are due to faults of the system, what Deming calls "common causes." Only a small fraction-called "special causes"-can be attributed to individual workers. "The worker can't do any better than the system," according to Deming.

The trick, then, is to find out how well a system can be expected to work-to find what Deming calls its "state of statistical control," its steady state-and to improve that. Statistical methods come into play here.

As expected, Deming's views sometimes aren't appreciated by management. "Managers often think they don't have anything to do with a production problem," he said in an interview. "I'll get called in and they'll expect me to find fault with the workers. But it's really their responsibility."

He added, "In Japan I taught management and management took it seriously. Here there have been only a few companies that have."

When Deming was finished lecturing, there was a question from an engineer. Could he say exactly how frequently a certain product-for instance, a cyclindrical tube that Nashua produces-should be measured in order to ensure standard quality?

Deming replied he would leave that decision up to the engineer. He wasn't at Nashua, he said, to make decisions for the company. He was there to teach an approach.

This approach, this overall concern for quality, has come increasingly to be recognized by U.S. managers in a number of industries. In television sets, semiconductors and cars, the major firms have already launched intensive efforts to close what many consumers perceive as a quality gap between American-made and Japanese-made products.

Nashua's president Conway is a convert. He has found in Deming's talks and writings the foundation on which to build Nashua's challenge to the Japanese. At the same time, Conway said he plans to expose the company's other divisions to Deming's message.

In addition to copiers, Nashua makes and markets a variety of products, including carbon paper and adhesive tape, typewriter ribbons and toners, magnetic discs for computers and chemicals for developing pictures. The company reported sales of $509 million last year.

In recent weeks, Conway has traveled to various Nashua outposts preaching quality control. He gives employes and managers a packet of papers written by Deming. Out of the papers is entitled, "What Happened in Japan?" It is clear Conway is using Deming as a catalyst, as the credible key to his program.

This is, Conway said, what separates this campaign from other quality control programs that have come and gone.

"we're talking about more than having a bunch of quality control engineers running around," he said. "We're talking about a kind of conditioning. I now see why the U.S. hasn't been doing all the Japanese have done. Very few top managers have been willing to sit in and spend the time listening to what Dr. Deming is saying.

"What he's saying," Conway added, "is make it right the first time."

Deming says he has about 30 or so clients. Some simply call on his statistical skill for conducting polls or for specific production problems. Others, like Nashua, turn to him as a recognized symbol for quality control.

At his age it would be natural if he were thinking about taking some time off. But the suggestion causes him to bristle. "Heavens no," he said when asked about the possibility. "Where would that leave my clients? It would be like a surgeon walking out in the middle of an operation." CAPTION: Illustration, No caption, By Margaret Thresher-The Washington Post; Picture 1, Above, Deming lectures the elite at Nashua Corp.; at left is the Japanese medal named in honor of his work for the country. By Tim Savard for The Washington Post; Picture 2, Deming answers a question during one of his seminars on "doing it right" for the Nashua firm. By Tim Savard for The Washington Post