ETA 2442
Description
If you pick up one of the common Flume movement finders, K2 or K3, you will come across the ETA 2442 at the latest on the second page of the size-sorted illustrations, which is not only the smallest ETA movement, but one of the smallest watch movements ever produced.
size compared to a 1 Euro Cent coin
Even a 1 Euro Cent coin is significantly larger than this marvel of miniaturization, which measures a mere 6 lines in diameter, or 13.3 mm.
As is often the case with ETA movements, it was available in different configurations, though in the exhibited examples these are limited to the color and type of balance wheel:
Version "Dugena 1211"
golden colored version with screwless Glucydur balance wheel
copper colored version
The design, which is identical in construction to the ETA 2412, is flawless, as can already be seen from the base plate, in which of course all important bearings are equipped with jewels:
base plate
Here too, the modern, space-saving gear train arrangement was used, in which there is no central minute wheel, but the hand mechanism is driven via the pinion of the third wheel.
The large mainspring barrel is connected to second wheel with its thick axle, followed by the third wheel, seconds wheel, and escape wheel. The latter must be inserted laterally during assembly.
gear train
The lever of this pallet lever system, like the escape wheel, is beared in olivedized rubies and is very difficult to assemble.
The balance wheel used in the examples at hand is always a large Glucydur balance wheel, which operates at a semi-fast 21,600 A/h and is beared in a pair of Incabloc shock protection devices.
The adjustment is made directly on the hairspring key, and unfortunately, it is almost a matter of luck to adjust the movement precisely.
side view of the gear train
As with the ETA 2412, the ratchet mechanism is located below the ratchet wheel.
ratchet
On the dial side, the pinion of the third wheel drives the minute wheel, on which the cannon pinion is mounted via a slip clutch.
dial side w/o hour wheel
Naturally, the ETA 2442 uses a yoke winding mechanism.
ETA 2442: Dial side
The different color variations can also be seen on the dial side:
dial side, golden toned version
dial side, copper toned version
In the lab
Timegrapher result
The movement was very difficult to regulate, but considering that it came from a “scrapped” watch, it still shows a satisfactory accuracy. Significantly better results could certainly be achieved in better condition.| horizontal positions | |||
|---|---|---|---|
| dial up | +-0 s/d | 283° | 0.1ms |
| dial down | +-0 s/d | 292° | 0.0ms |
| vertical positions | |||
| crown right (12 up) | +34 s/d | 226° | 0.3ms |
| crown up (3 up) | +31 s/d | 226° | 0.1ms |
| crown left (6 up) | +25 s/d | 229° | 0.1ms |
| crown down (9 up) | +35 s/d | 227° | 0.2ms |
Technical data
| Manufacturer: | ETA |
| Caliber: | 2442 |
| Caliber base: | ETA 2440 |
| Size: | 6''' (measured: 13,3mm) |
| Height: | 3,20mm |
| A/h: | 21600 |
| lift angle: | 53° |
| Number of jewels: | 17 |
| Escapement: | Pallet lever |
| Balance types: | Glucydur screw balance (two legs) Glucydur anular balance (three legs) |
| Shock protection(s): | Incabloc |
| Balance bearing / direction hairspring: | Clockwise |
| Moveable stud: | yes |
| Adjust mechanism: | Hairspring key |
| Construction: |
|
| Construction type: | solid construction |
| Winding mechanism: | yoke winding system |
| Setting lever spring: | 1 hole |
| References: | Flume: K2 2 |
| Mentioning in literature (years): | 1963 - 1971 |
| Inventory number: | 25013 |
Usage gallery
Amado ladies' watch (case missing)
Livano ladies' watch (case missing)
Arctos ladies' watch (case missing)
Dugena ladies' watch (case missing)
Priosa ladies' watch (case missing)