ETA 2412

Description

With a diameter of just 6 3/4 lines, the ETA 2412 is one of the smallest ladies’ watch movements on the market in the 1950s and 60s. Dugena gave it the internal designation Dugena 1201.

Over the course of its long production run, it was available in different versions, such as with screw balances of varying quality:

Of course, there were also screwless versions, also in varying qualities:

Und selbst bei der Farbwahl gab es mehrere Varianten:

Regardless of the version used, they were always impeccably crafted, as can be seen, for example, in the bearing fittings of the baseplate: all important bearings are equipped with rubies.

What’s special about this movement is that it no longer uses a directly driven center minute wheel, but instead, for space reasons, the hands are indirectly driven by the pinion of the third wheel on the dial side. The second wheel at the edge of the movement engages with the mainspring barrel.

The advantage of this design is that both the mainspring barrel and the balance wheel can be made very large in diameter, which on the one hand ensures a sufficiently long power reserve, and on the other hand ensures stable and good timekeeping.

Unfortunately, during assembly, the gear train is almost impossible to assemble without the mainspring barrel, and very difficult to assemble even with the mainspring barrel.

All versions use a balance wheel that oscillates relatively quickly at 21,600 A/h which is shock-protected by a pair of Incabloc shock protection devices. The slower oscillation (18,000 A/h) version of this movement is the ETA 2410.

The adjustment, at least in the versions presented, is always made directly on the hairspring key; the balance spring stud carrier is still fixed to the balance cock in the older versions, newer versions already have a movable hairspring stud carrier with which the beat error can be corrected.

The ratchet is mounted below the ratchet wheel.

On the dial side, one can see the familiar ETA construction with the yoke winding mechanism, the adjustment minute track, the preparations for the addition of further cap jewels (in the 17-jewel version) and the non-jeweled pinion of the third wheel (at position “8”), which drives the center minute wheel on the dial side.

The minute wheel is connected to the cannon pinion via a slip clutch, into which the change wheel engages, which in turn turns the hour wheel.

As already shown on the movement side, different colored versions can also be admired on the dial side:

In the lab

Timegrapher result