This well engineered Hamilton Thin-o-Matic Caliber 628 micro-rotor watch showcases the precision and elegance of 1960s automatic design. Our repair and restoration service returned this vintage Hamilton to good performance, including the replacement of a broken set lever screw with an authentic NOS part.
If you would like to initiate the repair of your vintage timepiece, be sure to visit getting started. For additional information on watches we work on please visit these pages: Vintage Rolex repair, Vintage Breitling repair, Vintage Omega repair, and Vintage Heuer repair.
Complete Service and Restoration of the Caliber 628 Movement
This Hamilton Thin-o-Matic watch, powered by the Caliber 628 micro-rotor movement, received a complete disassembly, cleaning, and lubrication service. During inspection, the set lever screw was found broken. A new old stock (NOS) replacement screw was sourced and installed, restoring full setting and winding functionality. The movement was then regulated for accuracy and tested for proper automatic winding. The Cal. 628 is a finely engineered mechanism, noted for its thin profile and efficient micro-rotor design.
History of the Hamilton Thin-o-Matic and the Caliber 628
The Hamilton Thin-o-Matic line was introduced in the early 1960s, during a time when watchmakers were racing to create ever-slimmer automatic watches. The Cal. 628 (actually a Buren Caliber 1280) movement is a compact derivative of the Heuer Caliber 12, known for its micro-rotor construction and precision engineering (learn more about the Caliber 12 here). Hamilton’s partnership with Swiss manufacturers like Buren enabled the brand to blend American design with Swiss mechanical excellence, resulting in watches that remain highly regarded among collectors today.
