IT'S SOME CLUB. There are six members in Washington, three in New York, a couple in California, one in Philadelphia and maybe 15 more in the rest of the world.

Now that's exclusive. What is it, left-handed, red-haired billionaires?

Not quite. They live right next to money, all right, sheets of it, shoulder-high stacks of it. But it's not theirs.

Meet the picture engravers, the guys who literally make money.

"We all know each other," said John S. Wallace Jr., who has been with the Bureau of Engraving and Printing for 10 years but spent many years before that with the American Banknote Co. His seatmate, Ed Archer, is another alumnus of American Banknote, which produces stock certificates and such.

"You get so you can recognize somebody's style," said Wallace. In the old days, engravers signed their work, but no longer. Occasionally someone will slip in a microscopic initial, but these rarely get by the inspectors. It's one of those games people play, like the bassoonist in the Boston Symphony who considered as his greatest achievement the interpolation of eight bars of "The Stars and Stripes Forever" into Rachmaninoff's Second, undetected.

"They don't trust me with trees," Wallace quipped, because once years ago he managed to work his initials into some foliage. The yearning for immortality is in us all.

The bureau also has eight letter script engravers and two sculptural specialists whose field is three-dimensional effects in embossing, notably in coins.

This is the kind of work you have to love. The apprenticeship takes 10 years, and even to get into the program you must pass rigorous tests. Meanwhile, the old veteran engravers are gradually passing, and new talent is needed. It's no longer the father-to-son business it once was. Most of the work is in stamps, but the currency dies have to be cleaned and repaired when they wear down in the process of printing 16 million notes every day.

But why do it all by hand anyway? Why not simply photoengrave the new bills and stamps?

"Security," replied Roland Williams, assistant chief of the engraving office. "If it's done by hand it's almost impossible to counterfeit, especially because several people work on every design. The Washington portrait on the dollar, for instance: That's 100 years old. We combine the parts on a master die. If we had to make an entire new bill, it would take four men a couple of years, full time."

When a plate is extensively touched up, say, by renewing the crosshatching, those bills are issued as a new series. The last major change in the $1 bill was in 1962.

He pointed to a stamp, a woman's portrait that Wallace was making from a six-inch pencil drawing. Working under a magnifying glass, he incised tiny lines, reproducing the portrait less than an inch high with excruciating precision. Wallace, like the other engravers, is an artist. But he has to be a very special kind of artist, because he is not allowed the slightest deviation from the design, no little creative additions, no cadenzas.

"Now here's why counterfeiting this stuff is hard," he said, carving an X on the linoleum desk with his delicate graver. "Look at the intersection of those lines in the glass. The points are perfectly defined. If you worked from a photographic copy of that, the definition wouldn't be as sharp in each tiny intersection of lines. That's why the pictures in counterfeit bills have a muddy look."

The engravers and their friends live a cozy life in their engagingly frumpy old offices on 14th Street. Everyone knows everyone else. The security is painstaking. Curious: They spend their working hours behind bars, seeing to it that counterfeiters are likely to wind up behind bars too. Only without a key.