In the face of a previously unpracticed problem, the approach to solving it is often far more important than effort.
Chen Zhou's idea, though bold, couldn't withstand the fact that the material used to make the block was too special. Its excellent properties gave the lead casting method plenty of room to play.
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On May 21st, when Chen Zhou began his attempt, he succeeded in casting a lead key blank in just two tries.
To be more precise, he actually succeeded easily with just one attempt—
Because during the first try, the lead inlet reserved was too small, making it impossible for the lead liquid to successfully enter the mold. Strictly speaking, this wasn't a failure.
After the lead liquid inside the mold solidified and cooled, he broke open the white clay wrapped around it, and Chen Zhou obtained a key blank closest to the correct answer.
He meticulously polished the entire key smooth.
