In the seventh lesson of his watch repair series, Alex Hamilton highlights the critical role of “end shake” and mechanical tolerances in ensuring a movement operates correctly. He emphasizes that because these clearances are too small to measure with standard tools, developing a visual and tactile “feel” for proper part interaction is essential for any watchmaker. The tutorial provides detailed demonstrations on inspecting the vertical play of wheels, the flatness of hairsprings, and the condition of pivots and jewels. Hamilton also shares a practical “bonus tip” for identifying cracked or chipped jewels by illuminating them from beneath with a flashlight.
