Accumatic A-506
1965–1972 · Stainless Steel · Automatic
About the Accumatic A-506
Made from 1965 through 1972, the Accumatic A-506 is a clean, no-nonsense automatic on Hamilton's caliber 689A, running 17 jewels. Part of the broader Accumatic family of self-winding watches, the A-506 kept things simple: a round stainless steel case, sweep seconds, and a choice of dial finishes that gave buyers a bit of flexibility at the counter. The base configuration came on a strap at $59.95, with a bracelet version available for $65.
Dial variation is the main thing to sort out with an A-506. Hamilton offered a textured silver dial with raised gold markers as the catalog standard, but a black dial was listed as an alternate from the start, and examples also turn up with smooth black and textured gray dials. Raised gold numerals at 3, 6, 9, and 12 anchor whichever dial you find, so the overall look stays consistent even across variants. The seven-year production run means examples aren't hard to come by, which makes condition the deciding factor rather than scarcity.
From the Catalog
Hamilton's 1965 catalog listed the A-506 with a textured silver dial and raised baton markers, with an alternate black dial also available. Strap-mounted examples retailed at $59.95, with the bracelet version priced at $65.
Hamilton Catalog Images
1965
1966
1968
What to Look For
| Dial | Look closely at the dial surface under good light. On silver or gray textured dials, check for discoloration, spots, or separation around the raised markers. On black dials, inspect for fading or uneven color. Avoid anything with moisture damage or a cloudy look near the center, and be cautious about dials that have been cleaned, since the lacquer finish does not hold up to solvents. |
| Crystal | These take a flat acrylic crystal. Deep scratches can be polished out, but cracks or chips mean a replacement is needed. A hazy or yellowed crystal is normal for the age and inexpensive to address. |
| Movement | The 689A should wind from wrist motion and run continuously without any need for shaking or hand-winding to keep it going. If it stops when set down and only picks up when moved, dried lubricants are the likely cause. A service is overdue on most examples at this age regardless of whether the watch appears to be running fine. |
| Case | Stainless steel holds up well, but check the lugs for wear and the caseback for pry marks or stripped threads. The case back on these can be stubborn to open, which sometimes means previous owners got rough with it. |
| Crown | The crown should pull out to the time-setting position smoothly and push back in with a positive feel. Sponginess or resistance can indicate a worn stem or damaged crown tube. Even though the original spec included weatherproofing, do not assume any vintage example is water-resistant with seals of unknown condition. |
The Movement
The caliber 689A is Hamilton's 17-jewel automatic, built to wind from the motion of the wrist through a rotor system rather than requiring manual winding. It runs a sweep seconds hand, which gives the dial a more dynamic look than a traditional subseconds dial. The 689A is a capable workhorse movement, though after 50-plus years the lubricants are almost certainly dried out, meaning a full service is the right starting point for any example that hasn't been recently cleaned.