Actual production methods: Detailed description of the production of waterwheels, such as pig iron casting in the Eastern Han Dynasty and steel pouring method in the Song Dynasty, selection and drying of wood, and tolerance matching of key components. Each technological improvement resulted from specific production challenges (silt clogging of riverbeds, changes in water velocity).
· Fictional social background: Place the rupture of technological inheritance in the context of dynasty changes, war turmoil, and changes in the social status of craftsmen (such as official craftsmen → military craftsmen → civilian craftsmen).
