ETA 853

 
ETA 853

ETA 853

Description

With a diameter of 31.4cm (14 lignes), the ETA 853 not only belongs to the larges movement, which ETA ever made, but also to the largest movements, which were used in contemporary wristwatches.

base plate

base plate

The execution of this movement from the late 1049s is very well. It is a massive construction, has got a large mainspring barrel and of course uses in all important bearings rubies.

gear train

gear train

The gear train with its classical execution is like from a textbook.

The mainspring barrel drives the center minute wheel, followed by third wheel, seconds wheel at 6 o’clock (with prolonged axle on the dial side to carry a seconds hand) and steel escape wheel.

Because of the large size of the movement, the gears look very filigree in comparison.

side view of the gear train

side view of the gear train

The ETA 853 uses a monometallic screw balance as regulating device.

As usual at that time, it is not shock protected and beats with 18000 A/h. A long regulator arm is used to adjust it.

Detail: Lever

Detail: Lever

A funny detail of the specimen shown here is, that is lever has got to differently colored pallets. While they look interesing, it should not have any technically effect.

ETA 853: Dial side

ETA 853: Dial side

Nice and tidy looks the dial side, on which you can see the yoke keyless works.

Around 1 o’clock, you can see a few minute markers. They were used to allow a regulation of the raw movement without the need for a dial.

In the lab

The specimen shown here came well used and with a slight water damage into the archive and got a simple cleaning with oiling afterwards.

Timegrapher result

The rates are not really well, without spare parts, it is unlikely, that they improve.
The amplitude values are missing here, because they were mistakenly traced with 52° instead of the correct 44° lift angle.

horizontal positions
dial up +21 s/d 1.8ms
dial down +43 s/d 1.7ms
vertical positions
crown right (12 up) -7 s/d 2.6ms
crown up (3 up) +34 s/d 2.7ms
crown left (6 up) -57 s/d 2.2ms
crown down (9 up) -91 s/d 1.9ms

Technical data

Manufacturer:ETA
Caliber:853
Size:14''' (measured: 31,4mm)
A/h:18000
Number of jewels:15
Escapement:Pallet lever
Balance types: monometallic screw balance (two legs)
Shock protection(s): none
Balance bearing / direction hairspring:Clockwise
Moveable stud:no
Adjust mechanism:Long regulator arm
Construction:
  • lever
  • escape wheel
  • seconds wheel, third wheel, center minute wheel
  • mainspring barrel
Construction type:solid construction
Winding mechanism:yoke winding system
Setting lever spring:2 hole(s)
Features:
  • s (decentral seconds)
References: Ebauches: 1949 62
Feilner: 39 3037
Flume: 1947 43
Inventory number:21026

Usage gallery

Dogma gents watch

Dogma gents watch

This movement is a kind from donation from Lars Schröder to the movement archive. Thank you very much for your great support!