The pencil tip slid a crooked line across the metal sheet. Chen Hao clicked his tongue and shook his aching wrist. He pressed the steel ruler down again, his fingers gripping the edge tightly, afraid it would shift. But with another bit of force, the thin metal plate beneath the ruler actually lifted up slightly.

"This thing's got a temper," he muttered, reaching out to press it with one hand. But his elbow bumped the table, causing the water glass to wobble and almost spill onto the drawings.

Nana reached out and moved the cup aside, her movements so light they barely stirred. She didn't speak, only stared at the bent piece of sheet metal; the terminal interface had automatically redirected to the material stress simulation page.

Chen Hao took a deep breath, changed his posture, squatted down, braced his knees against the table legs, and used both hands to push the saw while holding the ruler. The saw had only moved a couple of times when the teeth got stuck, like teeth biting into a crack in a rock. He put in a little more force, and the saw blade snapped with a "bang," the half flying out and bouncing off the welding machine casing before rolling into a corner and disappearing.

“Another heroic sacrifice.” He picked up the remaining saw handle and looked at the chipped serrations. “How long did it cut? It didn’t even cover a fingernail.”

He threw the broken saw into the scrap bin, where three other saws lay in the same fate. He wiped the sweat from his brow, sat back in his chair, and the chair back creaked under the weight.

"Do you think this steel plate is deliberately trying to make things difficult for me?" He looked up at Nana. "If it could talk, it would be laughing right now."

Nana brought up the data panel: "This plate is high-manganese wear-resistant steel, originally used for old-style crusher liners, with a tensile strength of about 850 MPa. The carbon steel saw blade you are currently using is less than one-third as hard, making cutting it like cutting stone with tofu."

"So it's not that my skills are bad, it's that my tools are just feeding me kills?"

"The conclusion is valid."

"How about we change the saw blade? I heard that alloy steel blades can handle hard materials."

"Only two tungsten carbide bimetallic saw blades remain in stock. They are suitable for benchtop band saws, but manual operation can easily lead to brittleness due to poor heat dissipation."

"So you need special equipment for this?" Chen Hao rolled his eyes. "I thought that as long as you're willing to work hard, you can really grind an iron rod into a needle. Now it seems that before you've even ground the needle, you've exhausted yourself grinding it."

He stood up and stretched his wrists, then walked to the corner, opened a storage cabinet, and pulled out an old angle grinder. The machine was rusty, and the switch was wrapped with electrical tape.

"Want to try this?" He patted the casing. "It shakes like Parkinson's, but at least it's electric."

Nana glanced at the equipment status: "The spindle eccentricity is excessive, and the protective cover fixing bolts are missing. It is recommended not to use it."

"It's okay, I'll cover it with my hand." Chen Hao plugged in the power, and the machine vibrated and hummed after being turned on, making his grip numb. "See, it can still turn!"

He picked up the piece of sheet metal, placed it on the workbench, and used several nuts to hold the edges in place as a clamp. Just as he started the angle grinder and brought it closer, the sheet metal suddenly trembled, jerked up sharply, and the grinding wheel grazed the edge, sending sparks flying.

"Oops! It's veering off course!" He hurriedly pulled his hand back, but the impact caused the angle grinder to slip from his grasp and crash onto the table with a bang. The switch popped out, and the machine shut down.

The sheet metal lay there, its edge chewed into a wavy notch, looking just like the sole of a slipper that had been gnawed by a dog.

“This isn’t cutting, this is performance art.” Chen Hao rubbed his burning palm. “What we’re doing now is called ‘challenging modern metallurgical achievements with primitive methods.’”

Nana has proposed three alternative methods: "First, chiseling method - using a cold chisel in conjunction with hammering to gradually separate the material; second, fire wire cutting - using high-temperature oxidation reaction to melt the metal; third, grinding wheel cutting method - using a hand-held grinding wheel to repeatedly grind along the marked line, which is time-consuming but highly controllable."

“None of these sound good.” Chen Hao shook his head one by one. “The first one requires blacksmithing skills. With my hand strength, I’d smash my fingers nine times out of ten. The second one requires oxygen cylinders. Our cylinder was almost empty when we were welding the windmill, so we need to prioritize repairs. The third one… how long did you say it would take? Forty hours?”

"Based on the current dust protection level and intermittent work rhythm, it is expected that we will need to work continuously for four days, ten hours a day."

“Then I might as well just lie down.” He sighed. “Making a small model takes half a month of my life to make. If I actually make an electric plow, I’ll be buried in the ground as fertilizer for it.”

He picked up the deformed sheet metal and examined it from all angles. Suddenly, he asked, "Couldn't we try a softer material first? Like an aluminum plate? Or maybe just use a thick sheet metal? It's just a model anyway."

After scanning the inventory, Nana responded: "The yield strength of the existing aluminum plates is only 31% of that of the target steel, which will seriously distort the stress test; the galvanized iron sheet is less than two millimeters thick and cannot simulate real tillage resistance. The test data is invalid."

"So we have to use this 'tough steel plate'?"

"Otherwise, the test would be meaningless."

Chen Hao was silent for a few seconds, leaning against the table, staring up at the gaps in the roof where light was seeping through. After a long while, he said softly, "I always thought that as long as I wanted to do it, I could always get it done eventually. But now I realize that not everything can be solved by just waiting." He turned to look at Nana, "Do you know what's most frustrating? You have all the knowledge in the world in your head, you can calculate the force distribution at every angle, you can design perfect structures, but when it comes to actually doing it, we're still stuck with a broken piece of iron."

Nana looked at him calmly: "Knowledge cannot replace physical conditions. I can provide the optimal path, but execution still depends on available resources."

"So the problem isn't the idea, nor the blueprints," he said with a wry smile. "The problem is that we don't even have a tool that can properly cut a piece of iron."

He straightened up, walked to the welding machine, lifted the side panel, and checked the wiring. Then he took out the welding torch, adjusted the current, lit the flame, and burned a red-hot line along the edge of the iron plate.

"Try hot cutting?" he said. "Heat it up to soften it, then use a handsaw to cut it while it's still hot."

Nana cautioned, "Local heating may cause a phase transformation, which can actually increase brittleness."

“I know the risks,” he said without looking up, “but we have to try, otherwise we’ll end up with nothing today.”

After the flames burned for five minutes, the edges of the steel plate turned a dark red. He quickly put down the welding torch, grabbed the newly replaced saw blade, and pushed it upwards. After only two sawing strokes, there was a crisp "snap," and the iron sheet shattered directly along the heated area, the crack jagged, like a broken biscuit.

The test panel was scrapped.

Chen Hao stood frozen in place, still gripping the saw, his forehead covered in sweat. He slowly squatted down, plopped down on the ground, and gasped for breath.

"It's over," he muttered. "I can't even make a toy."

Nana bent down and carefully picked up the fragments, sorting them neatly. She offered no words of comfort, but instead pulled up a new document with the title: "Feasibility Analysis of a Simple Metal Processing Device."

"This failure was attributed to uncontrolled heat treatment, resulting in localized embrittlement of the material. We recommend focusing on developing or acquiring alternative processing tools for future applications."

Chen Hao looked up at her, his eyes somewhat vacant. After a long while, he slowly spoke, "Tools...we don't have any ready-made, so we'll just have to make one ourselves?"

He slowly stood up, brushed the metal shavings off his pants, and walked to the storage rack in the corner, piled high with miscellaneous items. Inside were scrapped motors, twisted steel pipes, half-finished pulley systems, and gearbox casings left over from who-knows-when.

He reached in, pulled out a rusty bench vise, shook it, and found that the fixing bolts were long gone.

"If this thing were still usable, it could at least hold the iron plate in place." He examined it from all angles. "It's a pity it doesn't have a base, so it can't be mounted on a table."

He then pulled out a small DC motor; the label was blurry, but it could still turn. He tried connecting the battery, and with a soft hum, the shaft began to rotate.

“This motor… isn’t very powerful, but if you pair it with a saw blade…” His eyes lit up for a moment, then dimmed again, “but there’s no support frame, no transmission, not even a decent pulley.”

He placed the motor on the table and stared at it for a long time.

Nana stood to the side, the terminal interface still on the first page of the feasibility analysis, waiting for instructions.

The workshop was quiet, with only the welding machine's cooling fan still running at a low speed, emitting a soft hum. On the table, the blueprint that read "First Generation Electric Assisted Plow - Prototype Project Launch" was somewhat blurred from being rubbed, and there was a bit of oil stain in the lower right corner.

Chen Hao suddenly turned around and pulled open the bottom drawer of the tool cabinet. Inside, wrenches, screws, broken drill bits, and several discarded circuit boards were haphazardly crammed together. As he rummaged through them, his fingers touched a heavy metal block.

Upon closer inspection, it turned out to be an old-fashioned flywheel with teeth-like patterns on the edges, as if it had been salvaged from an old machine.

He weighed it in his hand and then looked at the badly worn grinding wheel on the angle grinder.

"If only we could modify the flywheel into a saw blade... and then use a motor to drive it..." he muttered to himself, "Although the precision wouldn't be great, at least we could cut out a rough shape."

He looked up at Nana: "Do you have any reference designs for this kind of simple method? It doesn't need to be very precise, as long as it can rotate."

Nana has already started searching: "There are similar cases - during World War II, field workshops used car generators to modify cutting devices, with an average cutting efficiency of 23% of the standard equipment, but with emergency availability."

“That means it works.” Chen Hao put the flywheel on the table and dusted it off. “We’re not looking for efficiency now, we just hope the saw doesn’t die so badly again.”

He picked up a pen and drew a rough sketch on a scrap of paper: the motor was erected vertically, the flywheel was mounted on the side, and a rubber ring was used for transmission in the middle. The base was welded with angle iron and then weighed down with a heavy object.

"It may be ugly, but as long as it can move, that's a victory," he said. "This time, I'm not in a hurry to cut the plowshare; let's make something that can cut iron first."

He pushed the sketch in front of Nana: "Take a look and see if there are any obvious flaws? Like the kind that explodes as soon as you turn it on."

Nana glanced at it and marked three risk points: transmission slippage, unstable center of gravity, and lack of protection.

“It can be modified.” Chen Hao pointed to one of the locations. “Add a tensioning wheel here, and weld two triangular supports there. As for protection…” He looked around, his gaze landing on a piece of scrap metal. “Cut a piece and use it to enclose the area; it’s better than nothing.”

He stood up, walked to the welding machine, and casually picked up the welding helmet and put it on his head.

“Since this piece of iron refuses to bow down,” he pressed the start button, and an electric arc flashed, turning half of his face blue, “then let’s build something that can make it bow down.”