By the time Jup reached the apartment, the machine had reclaimed most of his attention.
Saturday had done what he wanted it to do.
For a few hours, Northline had pushed the scanner, Darnell, Liz’s warning, and the unfinished frame far enough away that he could enjoy being somewhere else.
Now the apartment door closed behind him, Sector Seven settled back around him, and the work waiting in his room felt less like an obligation than something he had already chosen.
Aya looked up from the kitchen when he passed.
“Good day?”
“Robert survived.”
“That wasn’t what I asked.”
Jup slowed.
“Yeah. It was good.”
The answer seemed to satisfy her more than he expected.
He went to his room, shut the door without locking it, and found the frame exactly where he’d left it beneath the desk lamp.
Two fitted sections, one support collar — a beginning small enough to look unimpressive unless you knew how many measurements were hiding inside it.
Jup sat down.
Northline hadn’t taught him how to build anything; it had let him see old problems from farther away: impossible loads shared across structures, failures isolated before they contaminated everything around them.
Different machines.
Same engineering truth.
Control the load.
Isolate the damage.
Never make one part solve two problems badly when two parts could solve them correctly.
Jup pulled the next schematic closer.
“All right.” He picked up where he’d stopped.
The remaining inner-frame supports had to seat without force while holding their position inside tolerances narrow enough to punish impatience.
Jup cleaned each contact surface before fitting it, checked the angle under magnification, and tested movement before tightening anything permanently.
The third support seated cleanly; the fourth did not.
It looked right — that was the problem.
Jup measured it once, didn’t like the number, and measured again.
The mounting face was off by less than a tenth of a millimeter.
“Of course you are.”
He loosened the section, reseated it, checked again.
Still wrong.
The frame came apart farther than he wanted before he found the cause: one micro-fastener had settled against the edge of its channel instead of the center, shifting the entire support just enough to matter.
Most machines would have corrected around it; his father’s machine expected him not to make the mistake.
Jup fixed it, put the frame back together, and this time the measurement held.
He moved on to the regulator carrier, where four channels had to sit close without interfering with one another.
The fourth — the regulator worth several months of rent — made Jup wash his hands again before touching it.
He connected only the diagnostic feed.
No active crystal.
No adaptive chip.
No full power.
The first two channels held.
The third drifted as the housing warmed.
“That’s not drift,” he muttered.
“That’s attitude.”
Jup traced the heat to the lower carrier edge, adjusted the thermal bridge by less than a millimeter, and ran the cycle again.
Better.
One more test held clean.
Forty-three minutes to fix something nobody would ever see.
He understood exactly why he had dreaded this.
A knock touched the door, and Aya came in carrying a plate.
She looked at the desk, then at him.
“Close?”
Jup laughed once.
“Absolutely not.”
“Good.”
“That’s a strange response.”
“Means you still know what time is.”
She set the plate beside him, safely beyond the tools.
“Eat while it’s warm.”
Jup glanced toward the frame.
Aya followed the look.
“That’s what I’m afraid of.”
She left before he could negotiate.
He ate, and Dominique appeared while he was routing the first section of shielding around the signal paths.
She leaned against the doorway.
“It looks like a bug.”
“It doesn’t.”
“Robot spider.”
“Four limbs.”
“Disabled robot spider.”
Jup turned slowly.
Dominique smiled.
“I’m helping.”
“Go help Mom.”
“She sent me away.”
“Smart woman.”
Dominique disappeared, still pleased with herself.
Jup returned to the shielding.
His father’s material was thinner and less forgiving than anything he normally worked with; the layers had to follow the signal routes without interfering with the regulators or folding joints.
The first section went down cleanly; the second wrinkled at a turn.
Jup studied the wrinkle.
He could flatten it, could probably make it work.
He peeled the entire section back off.
Close enough had already cost him most of an hour once tonight, and he was not paying twice.
Near midnight, the inner frame finally held together.
The regulator carrier stayed stable, the shielding passed isolation, and every joint moved cleanly.
It was still mostly skeleton, but it was no longer a pile of parts.
Jup rested his forearms on the desk and looked at it.
Friday’s first connection had felt symbolic; this felt real.
He reached for the next schematic and stopped when his fingers cramped around the edge.
Jup opened and closed his hand once, then twice — the second time hurt.
He looked at the clock: 12:18.
His father’s letter sat beside the lamp.
Understand before you use.
Jup had always assumed the warning was about the machine; tonight, it applied just as well to his own hands.
He powered down the diagnostic rig, covered the regulator assembly, and left the adaptive chip untouched in its clear sleeve.
The hardest part of stopping was that he knew exactly what came next: the outer chassis, the folded limbs, the control paths, enough work to make Saturday night look merciful.
Jup stood, stretched until his back complained, and looked once more at the black frame beneath the lamp.
It had taken him most of the night to make something that still looked unfinished.
He smiled anyway.
That was engineering, and Sunday could have the rest.
Sunday morning found Jup back at the desk before his shoulders had forgiven Saturday night.
He rolled his right wrist once, checked that his fingers had stopped cramping, and opened the next section of the schematics.
The articulated assemblies were already familiar on paper; building them was less polite.
Each of the four limbs folded against the chassis and could brace, stabilize, land, or manipulate depending on what the machine needed.
The geometry made sense; the work required to preserve it did not get any shorter because he understood it.
He began with the left-front assembly, where the first bearing seated smoothly but the second stopped halfway through its channel.
Jup froze before instinct could turn resistance into force.
He removed the bearing and checked the channel under magnification.
A burr along the inner edge barely caught the light; three careful passes with a finishing tool removed it.
The bearing slid into place under its own weight.
“That’s better.”
The rest of the first limb took nearly an hour; the second went faster.
By the time Aya called him to breakfast, two assemblies were attached and neither had passed final calibration.
Jup went anyway, mostly because she used his full name the second time.
When he came back, Mark was standing in the doorway looking at the chassis.
“It grew.”
“That’s generally the plan.”
Mark stepped closer without touching anything.
“What does that part do?”
Jup followed his gaze toward one of the folded limbs.
“Depends on what the machine needs.”
“That answer sounded expensive.”
“You should see the regulator.”
“I have bills. I’d rather not.”
Jup smiled and returned to the desk.
The next few hours disappeared into pivot geometry and calibration.
The contractor-camera servos gave Jup a familiar reference while he tested his father’s movement system, which measured where a limb actually ended up instead of trusting the command that moved it.
Jup liked that more than he should have.
Never let a system grade its own work.
The third limb passed calibration on the second attempt; the fourth developed an argument with reality.
Too much rotation under side load.
Jup adjusted it repeatedly until frustration turned the problem personal.
On the sixth attempt, he realized he was correcting the wrong thing.
He pushed away from the desk and went to the kitchen.
Dominique looked up.
“Spider winning?”
“It is not a spider.”
“So yes.”
Jup opened the refrigerator while Aya hid a smile behind her cup.
He drank water and stayed away from the machine for ten minutes.
When he returned, the mistake practically introduced itself.
The pivot was fine; the mounting plate beneath it was flexing under load, changing the angle after the actuator had already stopped where it belonged.
Jup looked over the assembly.
“I owe you an apology.”
He redistributed the mounting pressure across the plate and ran the test again.
The limb stopped exactly on specification — few pleasures in life were as specific as finding out the problem had been somewhere else.
By early afternoon, all four limbs folded cleanly against the frame.
The black outer plates changed the machine faster: they overlapped instead of meeting edge to edge, each one protecting the structure beneath while leaving room for cooling, field clearance, and movement.
Jup fitted the left side, checked articulation, then mirrored the process across the right.
By then, the thing on his desk finally looked intentional from across the room.
Compact, low, four folded limbs tucked around an empty central housing.
Dominique appeared again and leaned against the doorway, and Jup waited.
“It looks less like a spider.”
“Thank you.”
“Now it looks like a spider with money.”
Jup closed his eyes, and she left laughing.
The control architecture took most of the afternoon.
Jup routed the control lines through the frame and tested each actuator with minimal current.
ACTUATOR 01 — PASS
ACTUATOR 02 — PASS
ACTUATOR 03 — RESPONSE DELAY 0.006
His father’s limit was two thousandths.
Jup traced the delay to a tiny break in the shielding near one joint, repaired it, and tested again.
ACTUATOR 03 — PASS
The fourth passed immediately, but he ran it twice more out of principle.
By sunset, the machine could move every structure Jup had installed.
It had no reason to — that came later.
The contact lattice waited next.
Jup unfolded it beneath the magnifier.
The material was delicate enough that tightening one point could shift another across the assembly, and every contact had to align with the central housing without touching the frame.
He started at one end, adjusted, measured, moved to the next, measured again, then returned to the first because the second had moved it.
There was no clever solution, no shortcut waiting for him to notice — only patience.
The lattice took almost two hours.
When the final point settled inside tolerance, Jup rested both hands on the desk and sat very still.
The adaptive chip remained inside its clear sleeve near the back of the work surface.
He had already studied it, already tested its reaction to Nia’s crystal, already watched gold cross its surface while a recorder lost frames.
Tonight he wanted nothing from it — not yet.
Jup checked the time; his hands were steady, but his eyes had started burning.
He could install the processor housing and keep moving, or he could turn one tired mistake into a weekend spent rebuilding work that was already correct.
Jup covered the chassis.
Sunday wasn’t over.
Neither was the build.
After a day spent finding out how wrong close enough could be, leaving something unfinished felt like the fastest way forward.