Alex Hamilton’s fourteenth lesson focuses on maximizing power and amplitude by correctly servicing the mainspring barrel, particularly in automatic movements. He details the essential inspection of the mainspring bridle—the “release valve” that prevents overwinding—and demonstrates how to diagnose and correct issues like coned springs or domed barrel lids. The tutorial provides advanced techniques for polishing arbor holes and arbors to a mirror finish to minimize friction, as well as a comprehensive guide to selecting and using mainspring winders. Hamilton also shares his preferred method for lubricating automatic barrel walls, emphasizing a light, centered coat of grease to ensure smooth bridle slippage without contaminating the mainspring coils.
