Frank Sunderman preheated the oven to 350 degrees, just like somebody baking cookies.
But in his oven, Sunderman had placed 16 chunks of black ceramic tile onto a cloth made of glass.
Nitrogen poured into the oven, and then sucked out to create a vacuum, and later warm chemicals shot in, vaporized, and soaked through.
Sunderman has happily worked this job for 22 years, waterproofing the tiles that cover space shuttles, the same tiles that protect astronauts from the searing heat of re-entering Earth's atmosphere.
It's a job that helped him raise a family and came with a wonderful fringe benefit — he watched more than 75 launches at close range, right outside the building where he works.
But this Friday, on the very last launch in the history of the space shuttle program, Sunderman plans to stay home. That will allow him and his wife to watch the historic launch from their front yard with their 5-year-old grandson, who will be wearing a blue astronaut suit covered with mission patches.
There is another reason for staying home, however.
"It's probably going to be a little emotional," Sunderman allowed. "I don't want to let 'em to see the big guy cry."
A generation of American workers is preparing for the final shuttle launch. It's a milestone in history, but for these workers, it's personal. For many of these employees of NASA contractors such as United Space Alliance, Boeing and others, this has been their last chance to turn a wrench on a ship that leaves Earth.
These are the more than 5,000 men and women who fixed and fine-tuned America's reusable spacecraft with their own hands. They cooked the shuttles' tiles. They pumped fuel stored at 423 degrees below zero and made snowballs out of the icy substance that collects around liquid oxygen lines. They mixed chemicals, sniffed for toxic fumes, pulled wiring out of orbiters and laced it back in. They scrubbed, tinkered, prayed, cried and cheered over behemoth rockets the rest of the nation sometimes ignored.
They came to know Atlantis, Discovery and Endeavour — and yes, the lost shuttles Challenger and Columbia — like you knew the bicycle you rode as a kid.
What many of these workers don't know, exactly, is where they and the American space program go next.
Atlantis is scheduled to lift off Friday and return to Earth on July 20, ending the 30-year space shuttle era.
A round of layoffs hits two days later.
• • •
Cape Canaveral has served as the launch site for American astronauts since the very first one, Alan Shepard, in 1961. Mercury capsules launched there, and so did Gemini flights and the Apollo missions that took 12 men to the moon.
Space shuttles have launched there since 1981, a 30-year period that makes up more than half the era of human space flight. Shuttle launches have become a Florida icon, an image that symbolizes the state almost as much as palm trees and alligators.
Launching shuttles 134 times — this week's will make 135 — has required an army of workers to prep, program, fuel, load and monitor them.
NASA and its contractors began building up their work force at Kennedy Space Center in the late '70s. For some, getting hired into the space program was a lifelong dream. For others, it was an opportunity, a job that paid well.
Eric Miner and Rene Arriens both work for NASA contractor United Space Alliance and began as electricians in the early 1980s.
Early on, they helped wire up Launch Pad 39-B, one of the pads used for space shuttles, which has since been deactivated. They discovered something odd in this job: America's gateway to outer space is smack in the middle of a wildlife preserve that is primeval Florida.
Arriens recalls "one time pulling one of the cables out of the cable tree and I ran head-into a raccoon. I don't know who was more scared." Miner remembers sharing his work space with alligators, eagles, snakes, foxes and the occasional bobcat.
Like a lot of shuttle workers, Arriens and Miner stayed on, stayed friends and rose through the ranks. Arriens got a coveted job on the close-out crew, working inside the shuttle orbiter while it's on the ground. Miner became lead hydrogen technician, working on the super-cold rocket fuel on the launch pad.
Although Arriens proved he's smart enough to work on spacecraft, he never slowed down long enough for a bachelor's degree.
"I get to go in the cockpit of space shuttles every day," he said. "I didn't want to give that up."
• • •
In the late 1980s, Sunderman had relocated from Pennsylvania and was trying to get used to working construction in Florida's heat. He tended to show up late and sweaty for church softball games. One of the older ballplayers finally told him: Frank, you need to put an application in.
So in July 1989, he began working at the space center, in a nondescript "Thermal Protection System" building. He loved the air conditioning.
But Sunderman and other workers soon learned their job was complex and critical. Each shuttle orbiter is covered with more than 24,000 tiles, which come in many sizes.
Work inside the Thermal Protection System building shows it's not just the minds of engineers that keep shuttles flying. It's also the steady hands of workers like Frank Sunderman's wife, Kay, who is originally from Trinidad. The two met on the job.
Kay Sunderman built much of her 22-year career out of something called the SIP layer. It stands for "strain isolator pad."
Wearing safety glasses and cotton gloves covered with latex, she would precisely cut a thin, felt-like substance using scissors or a cutting board. Most pads are set back half an inch from the edge of the tile, accurate to within 0.06 of an inch.
"After a while, you have that precision, you can tell a half-inch from a mile away. … You get calibrated eyes," she said.
After cutting the pads, she glued them onto 6-inch wide shuttle tiles, using precise amounts of glue, and put them in something called a "vacuum bag." A quality control worker checked them later.
Together, these pads serve as shock absorbers, reducing the strain on the shuttles as they plunge back to Earth.
Walking outside her building, she would see Atlantis, Discovery or Endeavour as they rolled over to the giant Vehicle Assembly Building, and sometimes pick out the parts of the shuttle she had touched with her own hands.
"When it's rolling out, I say, 'Oooooh, I know that tile,' " she said.
When a shuttle launches, "You say, 'This is a part of me going up. That's my hands on that.' "
But for a tile worker, a launch is only the beginning. They all know the biggest purpose of tiles and other protective materials is to prevent the shuttles from burning up as they plunge through 3,000-degree heat while returning to Earth.
After the landing, she said, "then you can breathe a breath of fresh air."
It still rankles Frank Sunderman that people sometimes think Columbia was destroyed in 2003 because of a failure with tiles. That's not exactly right. A piece of foam fell from the shuttle's giant external fuel tank, knocking a hole in a panel on the leading edge of a wing.
"I have no problem correcting them, you know what I mean?" says Sunderman. When he hears that, "It almost feels like you're to blame. . . . I know that's not the case."
• • •
Thousands of workers already have been laid off from NASA contractors, and many will work their last day on July 22.
Even for some of those still on the job, the work is dwindling — there's not much need for new tiles when the last shuttle already has been wheeled to the launch pad.
But Travis Thompson still has a job to do. He's the lead on the close-out crew, the select group of workers who bring astronauts into the orbiter just before launch and make sure everything is working inside.
His crew will strap the astronauts in for their final flight. They will close the hatch on Atlantis, and also on a chapter of history.
His job is technically demanding and hazardous in ways that might not be obvious.
Thompson will eyeball the inside of Atlantis like a hawk, looking for absolutely anything that shouldn't be there. Something as innocuous as a forgotten roll of duct tape could shoot around the crew compartment during launch.
On Friday, this crew will be among the few authorized to go near the shuttle, when it is brimming with flammable materials. The giant orange external tank, standing 15 stories tall, will have been filled with a half-million gallons of super-cold liquid hydrogen and liquid oxygen, and the launch pad will mumble with sounds of gases venting and hissing.
"You've got this black-and-white orbiter and all this steam, and it's alive," Thompson said. "You can tell, it looks like she's living. And you hear things that you don't hear on a normal day because of the cryogenics. … The whole pad's talking to you."
Sometimes he and his crew will see ice on an oxygen line and make a snowball out of it, or use a finger to write the mission number (the last one is STS-135).
"One of my guys said, 'You know, we should be videotaping this,' '' Thompson said. "I don't know why, all these years, we didn't think to do that.''
Maybe it's because Thompson, who has worked in the program since the late 1970s, always knew another launch was coming.
Now there is only one.
Thompson has been talking to people about staying on with the space program but so far has no guarantees.
"I've been wondering how I'll actually feel," he said, and then sounded like he didn't want to dwell on emotions too much. "I have to stay focused. I have to make sure we do everything right."
But he did allow himself a little reflection.
"I've been doing this for 33 years. It's all I've ever wanted to do. My job is to put American astronauts into spaceships, and it looks like I'm not going to be doing that for a while.
"A big part of my life," he said, "is going to leave on that launch pad."
Times photographer Stephen J. Coddington contributed to this report.