Millions of baby boomers are approaching retirement or have already given up their jobs, but many don't want to kick back. One man, Seth Goldstein, has received international attention for his work and creativity as a mechanical sculptor after a career as a biomedical engineer. His driving force in retirement isn't a paycheck, but passion, reports CBS News correspondent Julianna Goldman.

Goldstein, 75, has always liked working with his hands, so when he retired from the National Institutes of Health 13 years ago, he wasn't interested in just sitting around.

"I like things that move; mechanical things, and then the question was well 'What am I going to do?' and my wife Paula came up with an idea," Goldstein said. "Out of a clear blue sky, she said why don't you make a machine that ties a tie?"

Three years later, his tie tying machine came to life and his new career as an artistic inventor took shape. It's one of three machines he's built in his basement.

Is this how Goldstein imagined his retirement?

"I thought they would have to drag me out of that place," he said.

Goldstein is charting a course for the baby-boomer generation.

Census figures show there are about 76 million baby boomers and according to the American Association of Retired Persons, over the next 14 years about 8,000 people a day will turn 65 and more than half plan to retire soon after.

For retirees, finding a purpose and not simply slowing down, is critical to remaining happy and healthy.

"Seth is lucky. He has had this passion forever," Dr. Nancy Schlossberg said. "The unlucky ones are the ones who have a passion about their work, and they don't see any way to translate that in retirement years."

Schlossberg, professor emerita at University of Maryland and author of "Revitalizing Retirement," said retirement is like graduating.

"You have some people when they graduate from college, they know exactly what they want to do. Others are searching, others are struggling," she said.

One of those who searched is Seth's wife, Paula.

She, too, was an engineer who retired a year before her husband.

"Retirement was a gift in many ways to me. It became an opportunity for me to explore, 'Well, what is it? How am I wired?'" she said.

Paula tapped into her creative side, dabbling in nature sculpture and photography, and also writing plays.

"I spent a lot of my early years in retirement just exploring lots of different things to see what it was that gave me that same kind of pleasure and enjoyment as I saw in Seth," she said.

Goldstein is the first to acknowledge his machines don't provide any commercial value, but for him it's about something greater.

"It's the challenge, I think. The violin and the tie-tying machine - they're just great ideas and just the concept of doing it, it's just so neat," Goldstein said.

One of Goldstein's more machines is now on display at the American Visionary Art Museum in Baltimore. He spends about four hours a day, six days a week in his workshop.