Homemade rafts of Cuban exiles are extremely rare and floating away with them is a people's history.

BY DANIEL de VISE

Nelson Novoa built a good raft, the best in his town: triangular wooden frame built from fence posts, fat Russian inner tubes, bamboo mast, a sail sewn by his wife.

'Everybody said, `You want to go to China? You can go there,' '' Novoa, 55, recalled.

But Novoa was going to Florida.

Ten years and a day after the carpenter and six others set sail from Cuba, his raft, the Tio B, sits in a warehouse in North Miami-Dade, safe and dry, property of the Historical Museum of Southern Florida.

It is a rare survivor among the thousands of rafts that crossed the Florida Straits in the balsero exodus of August 1994.

Balsos, Cuban rafts, have been known since the dawn of the Castro regime in the 1960s. Balsero ingenuity knew no bounds. Rafters used tractor inner tubes for flotation, lawn mower motors for propulsion, hand-stitched sails to catch the wind. One group traveled with a firefly to light their compass at night.

Rafts once seemed as numerous as rafters in South Florida. They decorated restaurant patios and Lincoln Road fountains, filled museum exhibits and art galleries. A used-car salesman kept a collection of 400 rafts in an airplane hangar.

Now, all that is gone.

How many Cuban rafts -- from any era -- remain in museum warehouses, public spaces and private collections? Perhaps no more than a dozen.

The Smithsonian has one. Arturo Cobo, the legendary rafter advocate, has four. East Martello Museum and Gallery in Key West has one. The historical museum has three. Rafter researcher Juan Clark has one. One sits at Crandon Park on Key Biscayne, another in a concrete warehouse.

''These are the rafts that I keep for my memories,'' said Cobo, one-time director of the old Transit Center for Cuban Refugees. He keeps a raft in the driveway and three others around the side of his Pinecrest home, beneath a rain-soaked tarp.

Ten years after the peak of the balsero phenomenon, there seems little doubt that these desperate, dangerous, oddly ingenious crafts ought to be preserved.

''They're so incredible,'' said Felicia Guerra, author of the 1997 book Balseros. "If you don't see them in person, it's hard to believe they could have brought so many people to Florida.''

Built from scraps and fortified just enough to survive a single journey, the rafts were doomed from the moment they left the Cuban shore.

Rough seas broke them apart. Water and gravity dragged them, along with their passengers, to the inky depths. The Coast Guard sank them to clear the straits of flotsam.

Decay and indifference condemned the rest.

Humberto Sanchez, a passionate exile, dismantled his unrivaled collection of nearly 400 rafts in the late 1990s when he could no longer afford the storage. Creeping damp had destroyed much of the collection, and no one stepped forward to salvage the rest.

'It comes to the point where you say, `How much longer am I going to keep collecting these, and how long am I going to keep them?' '' Sanchez said.

Among the surviving rafts known to Sanchez and local museum officials, only one can be traced with certainty to the mass exodus of August 1994.

It is the Tio B.

Nelson Novoa built the triangular vessel over five hectic days at his home in the Havana suburb of Guanabacoa and named it for a Cuban television character who was chatty, like him. He'd witnessed the riots in Havana on Aug. 5 and watched Castro open the gates to citizens who wished to flee. He'd already built and discarded two other rafts, dissatisfied with his handiwork. He knew his time had come.

His group departed the evening of Aug. 21. They carried bread, water, salted coffee to restore lost sodium, extra inner tubes and a hammer to keep the craft in one piece.

The bread and water were spoiled within hours. The rafters drifted for 2 ½ days without nourishment, submerged to their waists in water they could not drink. On the third day, they rowed into a storm and captured rainwater on a stretched nylon tarp. They drifted past sharks, and past corpses: a boy of 10; a man with no legs.

A Coast Guard helicopter spotted the raft at midday on Aug. 25, 70 miles from Cuba. The rafters were taken to Guantanamo.

As the helicopter lifted, Novoa watched his Tio B shrink away.

The raft kept going, completing its voyage to Florida.

Two Lincoln Road business owners found it Sept. 1 on Soldier Key, south of Miami Beach. They set it up in a fountain outside World Resources Cafe on Lincoln Road, where it sat for weeks as a symbol of the balsero endeavor. Restaurateur Steve Rhodes later donated it to the historical museum, where it remains.

An article about the Tio B reached Novoa at the Guantanamo refugee camps. Only on Friday, though, was he able to see his creation again, in a North Miami-Dade warehouse near his home.

''Oh my god,'' he said, breathless as he glimpsed his raft. "My Tio B.''