The loose vise didn't disrupt Liu Li's rhythm; instead, it seemed to smooth things over—all the panic she had felt earlier disappeared, and when the timer started again, her hand holding the file was even steadyer than before.
Only one final step remained: assembling the machined punches and dies, along with the other parts, and ensuring they moved smoothly after assembly. This wasn't a simple matter of piecing together building blocks; even the slightest misalignment would prevent the assembly from happening, and even if it did, it would jam. Liu Li didn't rush into action. First, she gently rubbed the edges of the parts with a fine oilstone, removing the almost invisible burrs. Then, she used washing oil and cotton yarn to polish the mating surfaces until they shone brightly, ensuring there wasn't even a speck of iron filings—this thing was like a jigsaw puzzle; not a single impurity could be tolerated.
After wiping the parts, she mentally reviewed the assembly sequence again: first install the die, then the punch, and finally the locating pins and moving parts. She figured out where to clamp tightly and where to leave a gap. She placed the die steadily on the wooden pad, picked up the punch, and instead of pressing it down directly, she tilted it slightly so that the edge of the punch touched the die opening first. She used her fingertips to feel the "air" when the two metal surfaces were about to touch—she couldn't rush it; she had to let them "align themselves."
After adjusting the angle, Liu Li held her breath and gently lowered her arm, using that little bit of force to guide the punch to slide in. At first, it went quite smoothly, but when it came to the part where the coordination was most crucial, her heart was in her throat—she didn't hear any harsh friction sounds, nor did she feel any jamming; the punch seemed to have a suction force, slowly drilling into the die.
Finally, she heard a soft "click," like a key fitting perfectly into a lock cylinder. The punch slid completely into the bottom of the die, and the two parts fit together seamlessly, so perfectly that she couldn't feel the gap by touch! Liu Li breathed a sigh of relief. Without stopping, she quickly took the locating pin and pressure plate and installed them. She was especially careful when tightening the bolts, applying force evenly—she had to tighten them tightly without squeezing them too hard and deforming the parts.
After all the parts were assembled, Liu Li tried pushing the moving component—it was a bit tight, not quite smooth. She didn't panic; this was common in high-precision fittings. It might be that there were still small burrs somewhere, or perhaps it was slightly misaligned during assembly. Instead of disassembling it, she watched the movement of the moving component and slowly pushed it with her hand, feeling where it was tightest. After a couple of touches, she roughly knew where the problem was—a small protrusion might be on the auxiliary positioning surface.
She took a very small file, its blade gleaming, and gently rubbed it against the edge of the locating surface, as if touching it with her finger, carefully examining any small bumps that might be there. She'd rub it once, then try pushing the moving part; rub it again, and try again. Sweat dripped down her face, but she didn't bother wiping it away, her eyes fixed on whether the part was moving smoothly and steadily.
On the fifth try, she pushed the moving part again—and it slid smoothly! It glided perfectly evenly, without any jamming or looseness throughout the entire stroke, just as required by the blueprint! Liu Li straightened up, let out a long sigh of relief, and looked at the assembled parts on the table. The metal gleamed under the light, and it could move smoothly. She felt completely at ease.
The whistle blew to signal the end of the competition. The referees came over to inspect, using a pneumatic gauge to measure the fit clearance, an optical comparator to check the form and position tolerances, and repeatedly pushing the moving parts to check for smoothness. When it came to Liu Li's part, the referees watched for a long time, especially the veteran technician who had previously dealt with the bench vise problem. He personally measured several key data points, and finally put down his measuring tools, his tense expression easing a bit. He even quietly nodded and wrote comments on the record sheet.
Some of the other competitors looked dejected, while others were still fiddling with parts they hadn't finished assembling. Liu Li, however, remained calm, slowly tidying up her files and measuring tools—wiping each file clean and putting the tools away neatly. She knew that the unexpected incident earlier hadn't stumped her; instead, it had allowed her to showcase her true abilities. Now, she was just waiting for the final results, feeling no panic whatsoever. All her practice had paid off.
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