The “nip chips,” as the manipulator arrays were called, had a “mean time between failure” of one billion hours, which meant that by the end of a single pid one or two of them in a batch were probably on the brink of failure. So when the pid's second shift came in, the machines were shut down and the nip chips swapped out and recycled.
This created a huge demand for nip chips—which had no other use except the manufacture of fax machine print plates—so they were produced on-site as well, and then tested extensively before being placed into inventory. “Inventory” in Conrad's experience had always meant a room or building with an element-sorting mass buffer, a fax machine, and enough floor space to assemble and disassemble the equipment you were faxing. Here, though, it referred to an old-fashioned warehouse full of vibration-dampening shelves, holding row after row after row of tiny diamond vials filled with chemically inert argon, in which the nip chips awaited their turn on the print plate assembly floor.
There were other warehouses as well, for the storage of ore and semipurified element stock, and there were traditional inventories—here called “smalters”—which fed the element stock into mass buffers, which in turn fed, through “teleport valves,” the tiny fax machines which produced the atoms which were assembled into print plates by the stitching machines. And then there were the “clean rooms,” which were also filled with argon, so that the workers inside had to wear space suits. There were test chambers, where finished plates were tortured with heat and cold, vibration and caustic chemicals, electric fields and ionizing radiation. Those that survived were then tested functionally—faxing a series of increasingly complex objects—and then torture-tested again just to be sure.
Conrad was no genius, but it didn't take one to grasp what a huge undertaking this all was. Even sweeping the floors of this place was a formidable—and constant!—task. And yet the output—the brace of shipping crates in the finished product warehouse—was tiny. Despite the scale of the operation, the facility produced an average of just one print plate per day. And although their quality fell along a “multivariate continuum of lifetimes and probable failure modes,” the plates were sorted into three sales categories: personal, industrial, and medical.
“Faxing a cup of coffee is one thing,” Brenda explained. “You can tolerate a lot of impurity and displacement. The human body is a lot more difficult. You want it to still be living when it steps out, right? More than that, you want to preserve all its electrical potentials, or the person will be unconscious or dazed or amnesic. Sometimes psychotic. And the collapsing potentials have to be perfectly synchronized, or you'll see epilepsy and cardiac fibrillation, or worse. Testing on the medical-grade fax machines can get pretty ugly for this reason. The vast majority are rejected. And Conrad, seriously, don't ever let anyone talk you into feeding your body through an industrial plate. Even if it's life or death, you're better off taking your chances.”
While she was speaking, she handed a wellstone sketchplate off to another copy of herself. This place turned out to be crawling with Brendas—dozens or perhaps even hundreds of them. About one person in twenty was a Brenda, and they all looked tired and unhappy. A few glanced at Conrad in surprise, but hurried on with their business. The others simply ignored him, too wrapped up in their own affairs to pay any attention.
“Do you integrate all these copies?” Conrad asked, trying to keep the amazement out of his voice. His own brain threatened overload when he merged even three or four copies back together. He hadn't run any more plural than that even in the best of times, for fear that he'd damage his neural wiring and have to scrap the memories anyway.
“Only the variances,” she said. “I developed a filter for it: anything significant, anything that deviates from the norm, is weighted and blended with my baseline daily experience. I let the copies run for a few weeks, and reintegrate them in groups of five, then reintegrate the fivers to update the canonical me, whom you spoke with earlier.”
“Sounds complicated.”
She shrugged. “You get used to it. Anyway, no one else wants to volunteer for medical testing. I burn a lot of copies that way as well.”
“Ouch,” he said, with genuine sympathy.
“Yeah, tell me about it. I don't know what a hard failure feels like, because the memories of it are destroyed in the process, but judging from the sounds I make and the looks on my face, it's pretty damned unpleasant.”
“So every medical fax that comes out of this place has produced at least one Brenda?”
“More like a hundred,” she said, looking about as uncomfortable as people ever did while still keeping their composure. “We have to be sure there isn't a glitch somewhere. Unfortunately, generally speaking, there usually is.”
“Ouch,” Conrad said again. Then, feeling her need to change the subject, he said, “Tell me again why you can't just fax more fax machines? I've always known it was so, but I've never understood it.”
The unease of her expression was displaced by irritation. “I wish one person could come through here without asking me that. Really. Look, inanimate systems like a metal beam, or even a diamond monocrystal, are extremely forgiving. They practically assemble themselves, which is why even a personal fax machine can produce them. Food is even easier to build, although it's chemically more complex, because the placement of molecules in a dead biological system is kind of arbitrary. If the cell walls don't quite come together, who cares? You're just going to digest it anyway.
“Living bodies are difficult for the reasons we've already discussed, but even there you've got considerable slop in where and how you place the pieces. Our bodies are wet, flexible, self-correcting mechanisms. If you're careful, you can make near-perfect copies of them with only nanometer precision on the placement of atoms. DNA and proteins and fats are all extremely stable. The atoms want to fall into those patterns, or life could never have arisen in the first place. Wellstone is about as complex, though for different reasons.
“But a print plate is a whole other thing. In technical terms, it's a heterogeneous mix of quantum-wave structures supported by the level fluctuations of valence electrons. Even the sorriest, crappiest fax machine—a garbage disposal, say—requires zero impurities, zero defects, and picometer precision on assembly, which is five hundred times better than the fax itself can achieve.
“And even then, you've still got to get the waveforms right. Once they're established, the plate does fortunately have some damage tolerance. If it didn't, we could only use them in a bath of liquid helium, and the first object you printed would destroy the machine. But to get the fields up and running, you have to build the plate exactly right on the very first try. Ninety-five percent of the plates we manufacture go straight into the disposal.”
“So,” Conrad said as he struggled with all this new information, “you're using fully half the colony's resources, but the medical-grade faxes are a fraction of a fraction of a fraction of your total output.”