Seiko

lars martel
1

• Show profile
• Show other posts

Tide calculator versus tide clock

I’ve been looking closely at this Seiko, and I’m increasingly convinced it isn’t a “tide watch” in the usual sense at all but a tide wheel calculator built into a watch case.
On a true tide watch, the tide indicator is geared to the movement, so the tide hand or disc slowly advances as the clock runs. On this one, the three discs (outer tide scale and the two inner date/time dials) appear to move only when you turn them by hand, and do not rotate with the clockwork. If that’s right, it means the watch isn’t “telling” the tide in real time; you’re meant to align the wheels manually—exactly like an old‑school plastic or cardboard tide calculator—to estimate future tides.
So your experience actually makes sense: if you were treating it like a live tide indicator, it would be baffling. It only becomes logical if you think of it as a little mechanical tide slide rule that just happens to be living on a watch dial.