On the main floor of the Museum of Science and Industry, directly under the Boeing 727 and around the corner from the chick hatchery, Chicago’s skyscrapers soar above the shores of Lake Michigan as multiple trains carry commuters, haul coal and corn, and weave their way across the continent from Chicago to Seattle and back again.

“The Great Train Story,” the sprawling model railroad exhibit unveiled in November, stretches across the museum’s east wing, replacing the old model railroad, a hallmark since 1941 but mothballed last spring.

The Museum and Santa Fe Railway, as it was called, helped transform model railroading from a hobby into a national obsession. In its heyday, two million visitors a year followed the trains as they flew across 3,000 square feet of farms and towns and deserts and canyons. “It was the first of its kind,” says John Llewellyn, the new exhibit’s chief designer. “People were awed by its size and detail.”

By the late 1990s, however, the railroad “was in shambles,” he says. “By the time we took it down, only one locomotive was still operating.” In addition to being in disrepair, the exhibit was out-of-date and difficult to view through its thick protective shield. So the museum secured funding from Burlington Northern Santa Fe Railway and other sponsors to design a replacement with lots of action, spectacular scenery, and enough gadgetry to capture the interest of computer-age kids and adults. The only items salvaged from the old setup were the trees.

Designed to tell the story of how people and cargo are shipped around the country, the 3,500-square-foot new exhibit features 32 trains–including 20 that carry freight and 4 transcontinental passenger lines. In the Rockies, old-fashioned steam locomotives chug through the mountains; at a steel mill, freight cars haul pig iron back and forth. In Chicago, el trains rattle around the Loop, the Metra takes commuters to a neighborhood the exhibit crew has informally dubbed Bungalowe Square, freight cars crowd a dingy rail yard, and a tiny family of four is shown at Union Station, boarding a passenger train bound for Seattle.

Llewellyn and exhibit developer Jennifer Johnston began work on the new railroad in late 1999, and in 2001 they took a cross-country train trip of their own, traveling nearly 6,000 miles in ten days on Amtrak and shooting hundreds of photographs of the landscape rolling past their windows. Once they returned, they decided to focus on the journey from Chicago to Seattle.

“Chicago was a no-brainer,” says Llewellyn. “It’s always been a major transportation hub. We chose Seattle because it receives lots of cargo from the Far East, which is then transported throughout the country.”

The exhibit is irregularly shaped–almost like an M–and is protected only by a metal railing, affording a clear view of the railroad’s inner workings. It’s also rich in detail. The CTA and Metra trains look weathered; the tiny figures in a Boy Scout troop–ostensibly coming home from a camping trip–are a bit grimy. Animals wander the wilderness, pink flamingos are planted in backyards, and mountaineers scale the Rockies.

To create the landmass, the Chicago-based Scenic View design and fabrication shop made a computer mock-up based on a clay model by Llewellyn, then used plywood and wire mesh to construct a skeleton. Technicians sprayed foam urethane over that and, using more than 4,000 photos and 800 drawings for reference, molded it into shape in their 65,000-square-foot Pilsen warehouse. “It was like working with mountains of Cool Whip,” says Marc Shellist, the company’s co-owner.

Scenic View also constructed the 192 buildings that make up the Chicago and Seattle skylines. Most are the standard model railroading HO scale–1/87 the size of the original–but the Sears Tower, which would hit the museum’s ceiling if built to scale, is only 14 and a half feet tall, or 60 percent of HO. Once complete, the 88 pieces of the exhibit’s layout were carefully packed into dozens of semis and shipped to Hyde Park, where they were assembled over several months.

While Scenic View built the landscape, Miami-based Scale Models, Arts, and Technologies, Inc. was busy engineering the guts of the project. The two companies had to closely coordinate their efforts. “Everything had to fit together with a margin of error of 1/32 of an inch,” says Michael Hart, the Miami firm’s owner. “This was like building the frame of an aircraft together.”

Though digital technology has revitalized the model train market, the museum’s exhibit relies on old-fashioned electrical and mechanical engineering to run the trains, bridges, and other moving parts.

“Computer technology is all the rage, and it works great until something goes wrong, and then you’re dead in the water,” says Hart. “So we decided to use the conventional method–designing an electrical grid that controls the trains and other movable parts by changing and controlling the flow of electricity through electrical relays and solid-state electronics. And though it’s conventional, it’s pretty sophisticated wiring. It has to be, when you’re trying to run 32 trains at a time plus bridges and track crossings.”

While a crash might thrill onlookers, the thought makes museum types cringe. “It will be totally automated–the trains will be able to detect each other as well as breaks in the track,” Llewellyn says, a bit nervously. “But I can’t totally control what visitors throw on the tracks.” Something else Llewellyn is nervous about: the transcontinental passenger trains are all modeled after those of troubled Amtrak, which has teetered on the edge of collapse all year. “I hope it stays around, just for the sake of the exhibit,” says Llewellyn. “But if it folds, I guess we can market the exhibit as a history piece.”

The Museum of Science and Industry is at 57th and Lake Shore Dr. (773-684-1414). It’s open Monday through Saturday from 9:30 to 4 and Sunday from 11 to 4; admission is $9, $7.50 for seniors, and $5 for children, with discounts available for Chicago residents.

Art accompanying story in printed newspaper (not available in this archive): photos/Eric Fogelman.