SITTING AT her worktable in a second floor studio at the Torpedo Factory, Gerda Nugent tilts a crystal glass toward a small disk spinning on what looks like a large gray sewing machine. Glass powder flies onto a cellophane strip hanging from the ceiling, and a sign of the zodiac, lined in India ink, becomes deep and indelible on the crystal. Nugent stops and examines it closely, delicately as a dentist.

At 23, Nagent is a glass engraver with nearly 10 years' training and practice. Among her more important commissions was the inscribed ashtray - with a beveled rim like a king's crown, engraved "To the King of Entertainment" - that Carol Lawrence ordered as a birthday present for Bob Hope last month.

Her husband John, standing behind her next to shelves full of crystal, is a Georgetonw University student who can claim partial credit for Gerda's becoming one of the few glass engravers in the United States.

Nugent gets up, sets down the glass, looks like she needs to rub her eyes. "Engraving," John Nugent says, offering visitors small cans of tomato juice to brace them against the heat, "is borderline between art and craft."

Downstairs in a potter's studio is a plaque reading.

He who works with his hands is a laborer

He who works with his hands and his head is a craftsman

He who works with his hands and his head and his heart is an artist.

Gerda Nugent is mainly the latter, but she becomes a craftsman once in a while for relief from more delicate and enervating work.

For Nugent, relaxation means engraving monograms, which she can trace off stencils instead of designing from scratch. "We've got a dozen styles of lettering," John Nugent says, "anywhere from a roccoco style (50 cents a letter) to Gothic ($3.50)." That's if you bring your own crystal. If you buy it there, monogramming is free.

Original designs, such as the zodiac glass ($48), run up to $70, and engraved portraiture begins at $100.

"I sold my best piece two days ago," says Gerda Nugent - a long-stemmed vase decorated with roses that took four days' work and brought $250.

Nugent quits when she's tired, since there's no erasing an engraved mistake. She puts in four or five hours a day at her shop, GerdaGlas, seven days a week, though she spends most Sundays making sure customers' kids don't wreck the studio.

Glass engraving was born in Venice, tooled off to Austria in its infancy and "has always been very big," in Tyrol province, where his wife grew up with six brothers and sisters, according to John Nugent.

She was born in Brandenberg ("a very small town with 1,000 people," she says, handing over a travel brochure picturing snow-covered mountains and chalets) and enrolled at 14 at Kramsach Glass Technical School.

"In Austria, at age 12 or 13 you know what trade you're going to take up and whether you're going to college or not," John Nugent explains.

How, at the age, can you possibly be ready to pick a career?

"My family are all artists," Gerda Nugent says. "My uncle is a painter. It must be in my blood."

She spent four years at Kramsach, the worst of which was the daily commute. "I hitchhiked when I missed the bus," Gerda says, and laughs. "My mother hated me because I was always late. Sometimes the bus driver saw me and just went past because he wanted to cure me." Then she hired on at a glass shop in Kufstein near the Bavarian border. She was working in a display window when John, who'd gone overseas to study at the University of Innsbruck, walked into the shop in late 1975.

They married a year later, invested $4,000 in engraving equipment and moved to the United States.

John explains the decision: "In Austria, all shops must be closed by 6 p.m. weekdays. They're closed Saturday afternoons and all day Sundays. An engraver needs a master's license before she can open her own shop, and there are rules against too many engravers working in one town."

Aside from the business restrictions, a big reason for the move was that "America is where the money is," according to John Nugent. In Austria, "I worked awhile in an armaturen, making pipes, faucets, plumbing fixtures, for $40 a week. And a pair of pants cost me $40.

When she turns 24, Gerda Nugent will be eligible for the Austrian master engraver's license. But she says she doesn't need it.

"It would take 13 weeks to prepare for it," she says. "When I go over there, I will enjoy myself with my family, not studying."

She probably doesn't need the license. Around Washington, her works appear at Martin's in Georgetown, the Gift Horse shops in Alexandria and Annandale, and at White Flint Mall, as well as at the Torpedo Factory studio (683-4894). And she does a good deal of commission work.

A visitor returns the Tyrol travel brochure to Nugent and wanders out of the studio, toward the stairs. Gerda calls after:

"If you're ever in Austria and need a place to stay, my mother charges $4 a night, including breakfast."