ETA 2842

 
ETA 2842 | 17jewels.info - The Movement Archive

ETA 2842

Description

After the ETA 2840 and the ETA 2841, the ETA 2842 is the third iteration of the reduced ETA 2824-2, exclusively made for Swatch wristwatches.

What exactly the differences are between these three “Swatch” movements, is unknown, especially since the ETA 2842 featured here uses neither a plastic escapement nor a date indication.

ETA 2842: base plate

base plate

The base plate of this 11 1/2 ligne movements shows its high quality. All bearings, except for the center seconds pinion, contain rubies.

Since some other bearings don’t contain rubies, it uses “only” 23 jewels, and not 25, like the [ETA 2824-2].

ETA 2842: gear train

gear train

We have the standard ETA gear train here, with mainspring barrel, second wheel, third wheel (which drives the hands on the dial side), center seconds wheel and escape wheel.

The latter ones uses fewer teeth, since the beating frequency was reduced.

The ETA 2842 does not offer a hacking function, altough it is already prepared (upper pin next to the winding stem).

ETA 2842: side view of the gear train

side view of the gear train

Of course, a swiss pallet lever escapement is used, and as balance, the standard monometallic three-leg anular balance.

It beats with only 21600 A/h and can only be regulated directly at the hairspring key, which is inconvenient, since the hairspring key is located below the selfwinding module.

ETA 2842: different side view

different side view

The ETA 2842 uses no Incabloc shock protection, but the slightly cheaper Novodiac shock protection, which was later rebranded to Etachoc.

ETA 2842: w/o selfwinding mechanism

w/o selfwinding mechanism

The upper bearing of the second wheel is not a bearing ruby, but a white plastic bearing (at position 5 o’clock).

ETA 2842: lower side of the selfwinding module

lower side of the selfwinding module

.

This is not the only odd plastic bearing, on the selfwinding module, there are three further plastic bearings on its lower side. Their durability during decades will probably never be tested, since the plastic cases of the Swatch automatics often break on the lugs after several years, just like on the specimen shown here.

If you wind the movement by hand, the pawl changers turn with enormous speed, abd so does the oscillating weight, because the decoupling does not fully work. Because of this, you should wind it manually only, if it really neccessary.

ETA 2842: w/o oscillating weight

w/o oscillating weight

The pretty simple oscillating weight of the ETA 2842 is already ball-beared!

ETA 2842: inside the oscillating weight

inside the oscillating weight

On the yet empty dial side, you see at position 8 o’clock near the center the gears of the third wheel, which later drive the hand works.

Additionally, the color of the yoke keyless works is notable, since a golden tone is pretty unusual here.

ETA 2842: empty dial side

empty dial side

The pinion of the thrid wheel drives the center minute wheel, on which the cannon pinion is attached with a slipping clutch. The cannon pinion carries the minute hand and drives the changer wheel for the hour wheel.

ETA 2842: open display works

open display works

On the ETA 2842, the gears of the display works are covered to allow the use of e.g. transparent dials or even no dials.

It’s noteable, that on the left of this picture, you can see the preparations for a date indication. Probably, other versions of this movement might have a date indication.

ETA 2842: ETA 2842: Dial side

ETA 2842: Dial side

In the lab

This movement came in a badly treated case, but without any visual abusement traces or dirt into the lab and got a simple service and was adjusted (which was difficult, since the hairspring key is located below the selfwinding plate).

Timegrapher result

Absolutely impressive, what a fantastic result this movement shows on the timegrapher. And even when it’s just a momentary consideration and probably won’t be stable over a long time, it shows, how good even the simplest ETA movements are!

horizontal positions
dial up +1 s/d 279° 0.3ms
dial down +-0 s/d 278° 0.1ms
vertical positions
crown right (12 up) +-0 s/d 244° 0.2ms
crown up (3 up) +-0 s/d 247° 0.1ms
crown left (6 up) -3 s/d 233° 0.2ms
crown down (9 up) -3 s/d 242° 0.3ms

Technical data

Manufacturer:ETA
Caliber:2842
Size:11 1/2''' (measured: 25,8mm)
A/h:21600
lift angle:52°
Number of jewels:23
Escapement:Pallet lever
Balance types: monometallic anular balance (three legs)
Shock protection(s): Novodiac
Moveable stud:yes
Adjust mechanism:Hairspring key
Construction:
  • lever
  • escape wheel, seconds wheel, third wheel, large driving wheel
  • mainspring barrel
Construction type:solid construction
Winding mechanism:yoke winding system
Setting lever spring:2 hole(s)
Attachment of setting lever:plugged
Features:
  • SCD (direct center seconds)
  • AUT (selfwinding)
Inventory number:23006

Usage gallery

ETA 2842: Swatch Automatic (1993)

Swatch Automatic (1993)

This movement and watch is an anonymous donation to the movement archive. Thank you very much for the kind support!