Secometer B
1948–1952 · 10k Yellow Gold Filled · Manual Wind
About the Secometer B
The Secometer B was produced from 1948 through 1952, sharing its platform with a small family of sweep-seconds models that included the Secometer, Secometer C, and the Rodney. At its core is the caliber 748, an 18-jewel manual wind movement built specifically to drive a center sweep seconds hand rather than a subseconds dial, a feature that gave the whole Secometer line its name and its character. The case is 10K yellow Gold Filled, round in shape, and the dial came in at least two distinct configurations: applied gold numerals or a black figure version.
Surviving examples vary more than you might expect for a watch with a relatively straightforward design. The luminous painted numeral dials show their age differently than the applied gold numeral versions, and the lume itself is worth a close look for even application and no flaking around the numerals. The sweep seconds hand is one of the first things to check for originality, since it's a defining feature of this reference and a replacement that doesn't match the period can undercut the whole watch.
From the Catalog
Hamilton listed the Secometer B at $66.00 in 1948, describing it as a grade 748 with 18 jewels in a 10K natural gold-filled case, with the buyer's choice of an 18K applied gold numeral dial or a black figure dial.
Hamilton Catalog Images
1948
1949
1950
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1952
What to Look For
| Dial | Confirm which dial variant you have: applied gold numerals, luminous painted numerals, or black enamel figures. Each is correct for this model, but they present very differently and condition standards vary. On luminous dials, look closely for flaking or loss around the numeral edges, since painted lume can peel away over time even when the rest of the dial looks clean. |
| Crystal | Round acrylic crystals for this period are generally still sourceable, but check that the current crystal fits flush with no gap at the bezel edge. A poorly fitted crystal usually means someone used a close-but-not-right replacement. |
| Movement | The caliber 748 is genuinely difficult to service correctly. Reassembly requires four wheels to align simultaneously, and the escape wheel pivot breaks easily if any force is applied during that process. Ask directly whether the watch has been recently serviced by someone familiar with this movement. A 748 that has sat unworn for years will have dried oil creating enough friction to stop it, even if it appears to run when wound. |
| Case | Check the case back for signs of forced opening, tool marks or a deformed edge suggest someone got in there without the right equipment. The gold-filled surface on the case and lugs can wear through to brass at contact points, so look at the lug undersides and the back where it meets a wrist. |
| Crown | Confirm the crown is original or at least period-correct in profile. A mismatched crown on a round dress watch is easy to overlook but immediately noticeable once you know to look. Check that it winds smoothly with no gritty resistance, which can indicate debris in the keyless works. |
The Movement
The caliber 748 is an 18-jewel manual wind movement built around a center sweep seconds complication, meaning the seconds hand runs from the center of the dial rather than a separate subseconds register at 6 o'clock. That arrangement requires a more complex gear train than a standard layout, which is part of why the 748 has a reputation for being difficult to work on. It's a capable movement when properly serviced, but it rewards watchmakers who have spent time with it specifically.