Under the critical gazes of postal inspectors (hidden overhead behind one-way mirrors), of radio-equipped supervisors and of television cameras, scattered throughout the mechanized innards of building the size of about seven football fields, they lift and sort, lift and sort, lift and sort.

They are the mostly young, mostly frustrated workers at the Washington Bulk Mail Center. Behind the strike talk of recent days, they say, the big issue is not money, but time - specifically too much compulsory overtime work. There is, as one put it, "the feeling that we don't have control over our own lives."

Next on their list of concerns is safer working conditions. They say some of their injuries are a result of fatigue from the long hours.

Their preference for time off rather than time-and-a-half pay, which separates them from the majority of postal workers, is a growing phenomenon among workers in such highly regimented and tedious jobs, according to some labor experts.

Similar concerns have prompted recent wildcat strikes at bulk mail centers in the New York City and San Francisco areas. Just 16,000 out of about 550,000 postal craft employes work at these huge and controversial mail "factories."

Off duty, some Washington Bulk Mail Center workers have devoted themselves to lashing out not only at their working conditions but also at their unions and at the quality of the services their own workplace provides to the public.

They sell T-shirts of their own design, parodying the proud eagle trademark of the U.S. Postal Service with a cigar-smoking buzzard.

They publish a monthly underground newsletter called "Postal Strife" with headlines such as "You Mail 'Em, We Maul 'Em," announcing an "inside look" at the horrible fates that await parcels in the mails.

They lampoon their bosses in cartoons that they draw, and they make fun of the postal unions with equal vigor, dismissing them as "too management oriented" and ineffective in representing the workers' interests.

These activities are led by a small group of young mavericks who favor an illegal strike. They content that the recent tentative nationwide settlement between the Postal Service and its unions did not address the special problems of people who work in bulk mail centers.

The mavericks sense that there is little public support for an illegal strike but they feel that the is because the public "doesn't understand our jobs," said Judi Bari, 28, who is, among other things, Postal Strife's chief cartoonist.

"People think we [postal workers] all sit in windows and sell stamps," she said. She said she spends much of her time on the night shift lifting sacks that weigh as much as 100 pounds apiece.

The Postal Strife group "definitely gets more support here than the union," according to Donna Bradfield, an official of the American Postal Workers Union who works as a clerk at the Washington center, located in Largo, in an area of industrial plants and rolling farmland. "Especially on the night shift," she said. "They're younger and more radical. The day-shift people are more secure, have more family responsibilities."

Bradfield said she has trouble recruiting people to help with such routine union work as handling individual grievances.

The union and the Postal Strife mavericks agree on the issues Bradfield said but differ on the subject of a strike. "We're asking people to protect their jobs, and go through proper procedures" to ratify or reject the recent settlement. Bradfield said.

The Washington Bulk Mail Center, which employs 800 people, is part of a billion-dollar network of 21 such facilities nationwide, developed by the postal service in the last decade to an accompaniment of constant criticism, including revelations about mangled packages, delayed deliveries and soaring costs.

A report by the Government Accounting Office last month pronounced the bulk mail centers a failure in almost every respect, feeding speculation that at least some of them might be closed and adding to employes' uncertainties.

Some postal service officials respond that the highly mechanized centers are still young compared with the 200-year-old postal system, and that they need more time to work the "bugs" out, and study the people problems.

The inside of the Washington center resembles a sullen amusement park full of slow roller coasters traveling on a spaghetti-like tangle of tracks amid catwalks, conveyor belts, chutes and slides. A constant muffled drone comes from drive motors and an incessant clacking from carts carrying or dumping mail. The people seem dwarfed and overwhelmed by the machinery and isolated from each other.

The center handles between 400,000 and 500,000 pieces of mail a day, by official count - parcels, newspapers, magazines, government mailings, tires so-called junk mail. No first class.

According to David Drazek, an activist in the Postal Strife group, working at the center is an "unending Christman." And for postal workers, christmas means nothing but overtime.

'It's a tough situation," said another young postal worker, a bachelor who is "involved in Buddhism" and would like more time to spend on it. "On my day off, I'm too exhausted to do anything buy my laundry," he said.

The workers complain of being forced routinely to work 50 and 60 hours a week. One Postal Strife cartoon shows a father returning home from work, unable to recognize his children.

Like many other industrial employers, the postal service has a contract with its employes that permits it to require them to work overtime whether they want to or not, at time-and-a-half-pay. During normal periods, the maximum is an extra two hours a day, six days a week, but during December and in emergencies, those limits don't apply and the workers can expect to put in 12 hours a day, seven days a week.

Postal officials say the overtime requirements are balanced by the generous clause retained in the new settlement.

"We have tried to keep overtime to a minimum here - only what's necessary to move the mail," said Donald D'Andrea, an official of the Washington Bulk Mail Center. "But it's the nature of the beast that there will be peaks and valleys" in the flow of mail which are often unpredictable.

In the category of job safety, the workers tell of strained backs, of hands being sucked into machines, of a worker burned by acid from a package that broken open on a sack slide, of another being "attacked" by 12 meat cleavers that raced loose down a parcel slide, missing him narrowly, and a clerk who was knocked cold by an 80-pound box of encyclopedias that fell from an overhead chute.

Workers' compensation claims for on-the-job injuries have skyrocketed throughout the postal service, not just at bulksmail centers, in recent years, postal officials say. They blame this in part on a liberalization of the compensation law that they say made making claims easier and encouraged abuse.

But others, including many workers, charge that the machinery is poorly maintained, and they also blame fatigue and pressure to "work fast."

Julie McCarthy, general manager of the Washington Bulk Mail Center, said, We feel we are doing everything that we can be done [to establish safe working conditions] and are exploring ways to reduce accidents even further."

Members of the Postal Strife group said they will await the outcome of a strike vote by the traditionally militant New York union local, the largest in the country, before pressing for a walkout at the Washington facility.

"People are wary because of the firings [of postal workers who struck illegally last week], "Bari said. "If just a few of us go out, we'd be too easy to fire. "We're looking for safety in numbers."