I thought I could suggest a small but nice thread showing Eterna cal. 852 watches. The occasion is the completion of a repair of one of my current favorites, a 36.5 mm steel watch with the 852S - still without shock protection. The balance staff was broken, as well as the bearing jewel under the balance. In addition, the mainspring was weak. Now everything is like new and I am very happy.

Best regards - HU

 

A beauty, HU!

Congratulations, and all the best for the New Year.

 

It really is like new. Great photos of a beautiful example.

 

Fabulous watch, congratulations. I thought that the screwed in element seen under the regulator arm was part of some kind of shock protection on these great movements. No?

 

Correct. I should have written that the watch has an "early" shock protection. My point was to distinguish between the "early" shock protection (which I can't really imagine springing the baring jewels in such a way that the balance staff is halfway secured - especially since a really large balance is mounted) and the later shock protection concepts, where you can recognize from above that a spring is active.

Thanks Tony and of course the same for you!

Thanks also to DD12 who helped me a lot with this watch!

 

After a restless night with dreams of baring jewels, feathers and staffs, I spoke with my watchmaker on the phone. On my question whether he finds that the watch has a shock protection, he answered spontaneously with "No". On my objection that it must be a "kind" of shock protection (or intended as such) he said that then the steel plate on the balance cock (with the two screws) should be much thinner or softer - e.g. made of brass. But it looked as if someone had thought that construction at least in the direction of shock protection...

 

Here´s my other 852S (better shock protection...)

 

It seems that your watchmaker is commenting on the quality of the device, but it certainly is an early, Eterna-designed shock protector.



more from the source of the above image:

https://eterna-fanatic.com/shock-protection-device/

 

Interesting information about the stiffness of the steel plate, thank you.

 

P.S.:
On the main plate of the watch shown at the top, there`s a "L" in addition to "852S". I had not noticed that before.

 

Here's another 852S (similar to the one from the beginning of the thread, maybe a year or two older) with 37mm case in pretty good condition.