The model is constituted of an abrasive disk that turns on a vertical transmission shaft actuated by a crank. A connecting rod and crank system is mounted on the same shaft. An arm is attached to the connecting rod, which runs along the abrasive disk bearing the mirror to be polished. The crank is turned to produce two movements: the rotation of the abrasive disk and the simultaneous, alternating movement of the mirror mounted on the arm connected by the connecting rod and crank system, producing a uniform and regular polishing.
The model is based on the drawing:
- Codex Atlanticus f. 1103 v. (1513-1515)
Milano, Biblioteca Ambrosiana