This is a rare Universal Geneve (UN) Aero Compax Calibre 287 from 1946. This watch was marketed to international aviators who would benefit from an independently adjustable second time zone indicator along with a comprehensive chronograph for long flights. The crown on the left sets the timezone. No other chronograph of the era had this function. The inscription on the back references Chile and 1946. I serviced this watch for a family member who inherited it from their grandfather. The watch came to me in very poor condition. I was motivated by the potential of its beauty and historical significance. Full of rust, past watchmaker errors, and inherent parts scarcity, this watch offered significant challenges throughout the process. Broken parts, wrong screws, damaged manipulate, damaged balance, damaged hairspring, worn parts requiring adaptation, and as if this wasn’t enough, in the end the irreplaceable chronograph center seconds hand was unusable in its current state. On this movement variant the center seconds hand is very unusual. The pipe length and dimensions match nothing in today’s movements much less older movements and they are no longer available. There was only one option, which was to repair the hand. This is far more difficult than you might think because the g-forces on these chronograph hands are tremendous. Recreating the factory manufacturing process is not as easy as it may seem. The problem you hit outside of the precision of the very small pipe and reattaching it to the hand is the strength and precision of the tiny brass rivet you must make. If not perfect, the hand comes loose from its pipe and fails to function properly. After more than a no few attempts, I was successful. Once completed, the watch came together beautifully. Now functioning flawlessly and running with fantastic accuracy, amplitude, and beat error across all positions, the watch is ready to guide its owner and future generations on long flights once again.
