Thin-o-matic T-476 Calendar
1961–1962 · 10k YGF / SSB
About the Thin-o-matic T-476 Calendar
By the early 1960s, Hamilton's Thin-o-matic line was pushing the boundaries of how slim an automatic watch could be, and the T-476 Calendar brought a practical complication into that slim package. Made from 1961 through 1962, this model adds a date display to the round Thin-o-matic format, housed in a 10k yellow Gold Filled case with a stainless steel caseback. Within the Thin-o-matic family, the Calendar variants occupy a distinct spot, pairing everyday functionality with the line's characteristic low-profile design.
Gold Filled cases from this era can vary considerably in how well the plating has held up, so the lugs and case edges are the first place to check for wear-through to the base metal. The date complication also means there's a quickset or date-change mechanism to evaluate, so confirming the date advances cleanly through the night cycle is worth doing before committing to a purchase. Finding one with a clean, unpolished case and a dial that hasn't faded or separated from its base is genuinely satisfying given how hard these get used over sixty-plus years.
Hamilton Catalog Images
1961
What to Look For
| Dial | Look carefully at the date aperture surround for separation or discoloration, which can happen as dials age. Check that the overall dial surface is even in tone with no fading, spotting, or re-printing. |
| Crystal | Original crystals on these are acrylic. Deep scratches can be polished out, but a cracked or heavily crazed crystal should be budgeted as a replacement. |
| Movement | Ask when the movement was last serviced. Oil in a movement this age dries out and creates enough friction to stop it running altogether, so a service history matters even if the watch appears to be running. |
| Case | Examine the lugs and high edges of the case closely for wear-through on the gold filled surface. Once the base metal is exposed, there's no reversing it. The stainless steel caseback can be tricky to open, so look for evidence of tool marks around the back edge indicating rough prior handling. |
| Crown | Check that the crown threads or seats properly and that setting the date feels positive and controlled. A crown that slips or a date that advances inconsistently can point to wear in the setting mechanism. |