Accumatic A-504
1965 · Stainless Steel · Automatic
About the Accumatic A-504
Made only in 1965, the Accumatic A-504 is a stainless steel asymmetrical-cased automatic from Hamilton's Accumatic family, running on the caliber 689 with 17 jewels and a sweep seconds hand. The asymmetrical case was a recurring design gesture in Hamilton's mid-1960s lineup, and the A-504 shares that sensibility with related models like the Blade and the Electric Regulus. The dial is silver with applied baton markers, and some examples show textured markers at 12, 3, 6, and 9, giving those versions a slightly more dimensional look.
The applied baton markers are worth close attention on any example you're considering, since replated or refinished dials are out there and the fine detail of the marker bases is often the first thing to suffer. Finding one with the original silver dial intact and the asymmetrical case in good shape, without significant wear to the edges or case flanks, is genuinely satisfying given how compact the production run was.
From the Catalog
Hamilton listed the A-504 in 1965 at $65 on a strap and $69.50 on a bracelet, describing it as a stainless steel automatic with a silver dial and applied baton markers. The weatherproof rating was part of the standard Accumatic pitch at the time, though any vintage watch should be kept away from water regardless of its original rating.
Hamilton Catalog Images
1965
What to Look For
| Dial | Look for the applied baton markers sitting flush and straight, with no signs of separation, corrosion underneath, or amateur reluming attempts. On examples with textured markers at 12, 3, 6, and 9, check that the texture is consistent and not worn flat. The silver finish should be even, not blotchy or over-polished, and the lacquer layer should be intact. Do not attempt to clean a vintage silver dial like this, as the lacquer will peel and take the finish with it. |
| Crystal | The asymmetrical case shape means a replacement crystal has to fit correctly or it will look obviously wrong. Check for chips at the edges, deep scratches across the center, or any crystal that sits unevenly in the bezel. A correct-fitting crystal follows the contour of the case precisely. |
| Movement | The 689 is an automatic, so it should wind from wrist motion and run continuously without prompting. If dried lubricants have thickened over 60 years, there will be enough friction to stop the watch even if it seems to run briefly when agitated. A service should address that before daily wear. |
| Case | The asymmetrical case has edges and angles that show wear differently than a round case would, so inspect those curves and the case flanks carefully. Over-polishing tends to round off edges and soften the lines that make this case design interesting. Case backs on these can be stubborn to open, so avoid any example where someone has clearly forced the back and left tool marks. |
| Crown | Check that the crown threads smoothly and that the stem hasn't been compromised. The two-piece stem design used in this era is a known fragility point during movement removal, so any crown that feels loose, spins without resistance, or pulls out too easily deserves a closer look before purchase. |
The Movement
The caliber 689 is a 17-jewel automatic movement that Hamilton used through the mid-1960s in its Accumatic line. It winds automatically from wrist motion through a bidirectional rotor, with no need for manual winding under normal use. It's a reliable workhorse of a caliber, though like any movement of this age it benefits from fresh lubrication and a proper service before being worn regularly.