How To Build A T. Rex

Place dinosaur bones in empty warehouse. Add sculptors and fossil glue. Assemble.

By Jen Banbury
May 28, 2006 5:00 AMNov 12, 2019 5:59 AM


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When you drive around the outskirts of Paterson, New Jersey, past windowless taverns with scarred metal doors and warehouses on weed-wild lots, one of the last things you might expect to find is dinosaur fossils. And yet, pull into the driveway of a former foundry, push through the door and into an 11,000-square-foot studio with ceilings higher than the average church, and there they are: the fossil bones of Samson, one of the most complete Tyrannosaurus rex skeletons ever discovered.

This is the domain of Phil Fraley Productions, a fossil preparation and exhibit fabrication company—a realm of chisels and dust and glue, of long hours and, truth be told, as much art as science. Phil Fraley, 54, has been assembling dinosaur skeletons and preparing exhibits for the nation's top museums for 25 years. He directed a team that built a 40,000-cubic-foot rain forest for the American Museum of Natural History in New York City, and he has engineered everything from replicas of the leaves and buds of a groundnut vine at the Montauk Point Lighthouse Museum to the skeletal mount for Sue, the world's largest T. rex, at the Field Museum in Chicago.

Fraley, aided by his business partner and wife, Carol, surrounds himself with a team of young artists with strong visual sensibilities and experience with the construction techniques essential to dinosaur assembly. "We see things a little bit differently than scientists or researchers do," he says. "Researchers will spend the majority of their life examining a very small piece of an entire specimen, say the inner ear or the interior of the brain cavity, looking for morphological differences. But what they don't see is the overall picture, the overall animal. That's where we have an advantage."

Samson's bones came to Fraley in 2004, 12 years after members of the Detrich Fossil Company found them in South Dakota. The fossil hunters unearthed about 55 percent of the 65-million-year-old skeleton—encased in a mixture of mud and sand known in paleontological jargon as the matrix—and sold it to the British businessman Graham Lacey, reportedly for $5 million to $8 million. Lacey has yet to reveal where Samson's permanent home will be. In the meantime he has entrusted Fraley with the job of cleaning and assembling the skeleton for eventual display.

The first task for Fraley's team was to separate the bones from the matrix, an arduous cleaning process known as gross preparation. For months they sat at worktables and hunched over a parade of bones. The tool of choice is called an air scribe, essentially a handheld jackhammer with the look and sound of a dentist's drill that gently, incrementally chips the matrix off the fossil. Some matrix, like sandstone, comes away so cleanly and easily that it seems to jump free of its own volition. Other types can be tricky: Ironstone is often unyielding and so closely grafted to the fossil that it's difficult to tell where the bone ends and the matrix begins.

"It demands patience," says Donna Lopp. Like almost everyone on Fraley's team, Lopp was trained as a sculptor; her small size belies the fact that she is, among other things, a strong and accomplished welder. Her artist's instincts prove invaluable when coaxing bone from matrix. "It can be unforgiving. It demands a lot of patience and care. The stone is moody, unpredictable."

Few tools are built expressly for dinosaur bone preparation, so Fraley's team cribs freely from other fields: sculpture (wooden clay-modeling knives, double-ended carving picks, chisels, tiny spatulas, mallets), engraving (the air scribe, jewelers' loupes), and dentistry (carvers, probes, teasing needles). There are glues and penetrants for stabilizing the bones, hand-mixed resin concoctions for filling in holes, and denatured alcohols for cleaning. Two essential instruments are coffee and music. The team works with beehive intensity as an alt-rock sound track blares from a dusty boom box in the middle of the room.

After gross preparation, some of the team members moved on to the fine preparation stage of cleaning. For this, they use a microabrader, a tool resembling a corded pen that works like a very small sandblaster but uses gentler baking soda, talc, glass beads, and aluminum oxide. A finicky, labor-intensive process, it leaves the bones as smooth as skipping stones. Meanwhile, other team members began making silicone-rubber molds of Samson's bones for fabricating lightweight polyester-resin replicas. The gaps in Samson's skeletal display will be filled in with replicas of his own foot as well as the pelvis, some ribs, and parts of the tail of another T. rex.

Some of Samson's bones, ­including a 4-foot-4-inch-long femur and verte­brae that resemble polished coffee cans with delicate wings, are in near pris­tine shape. At the opposite end of the ­damage ­spectrum is a collection of more than a thousand shards that make up a jumbled three-dimensional puzzle. Most members of Fraley's team dread the sight of shards, but Tom Bugler, one of the on-the-floor supervisors, can pluck a few from a table and suddenly reconstruct the delicate arch of a rib. Bugler says it's a spatial-relations skill. "I've always been very good at packing a suitcase or the trunk of a car."

One part of Samson that Fraley and the team don't have to worry about is the skull. It is a beauty—perhaps the most complete T. rex skull ever discovered—and Fraley and Graham Lacey decided it should be prepared by a museum, where paleontologists could study it. The skull went first to the Carnegie Museum of Natural History's PaleoLab in Pittsburgh, then made a brief trip to NASA's Marshall Space Flight Center in Huntsville, Alabama, where scientists studied it with the same CT-scan equipment used to examine the space shuttle. But the fossil is much too heavy—close to 300 pounds—too fragile, and too valuable to perch on Samson's neck. So a cast will be made to serve as a stand-in, while the real skull will be displayed on its own eye-level mount near the animal's feet.

The most complicated stage in building a dinosaur is actually putting it all together. Early on, Fraley and his team had to decide what Samson's final pose would be. Running? Reaching? "I like to try to find a pose for the animal so that it's almost as if, within a blink of an eye, everything could change, and it could leap up," Fraley says. "That's something that has me . . . not waking up at night but definitely thinking." Samson is the fourth T. rex that Fraley has been involved in mounting, but that doesn't make it easier. Eventually, after trying out a number of options using computer illustrations, he and Lacey settled on a pose in which Samson's upper torso is slightly turned, as though he's just heard a Triceratops snorting behind a copse of trees nearby.

Samson's bones cannot stand on their own, of course. Instead they are supported by a giant metal framework called an armature—a skeleton for the skeleton—which requires precise engineering, custom welding, and plenty of tweaking. Many of Samson's ribs were significantly warped from their time beneath tons of rock and dirt. To give Samson a symmetrical rib cage, team leader Paul Zawisha will rig and rerig the ribs until they look right. A successful armature becomes virtually invisible to anyone staring up and through the monumental skeleton. The ultimate goal is to make all the mechanics and labor involved in assembling the skeleton disappear entirely, leaving the viewer with simple, slack-jawed amazement at the animal itself.

Fraley willingly admits that he is in awe of Samson and feels a special responsibility to make certain that the final mount does the magnificent T. rex justice. "The fossil begins to dictate the way that it wants to be put back together again, because it was, at one point in time, a living, breathing animal, no different from you and me," he says. "And that energy still exists—65 million years later, it's still there."

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