First successful service - Luvaco Chronometer

[fellerts]

I wanted to share the fruits of my recent labor: a Luvaco automatic housing an ETA 2472 chronometer grade movement. Not sure when it's from, but I'd guess the '60s.

 

I bought a lot of non-runners solely because I could just about squint "chronometer" from the listing. Included in the lot I also found a nice Certina and another ETA 2472-based watch which has been a bit troublesome recently, as well as a handful of ladies watches.

I recorded the initial uncasing. Never did I expect an absolutely _perfect_ dial under that dirty and cracked crystal! The hands have some discoloration but I don't mind as it's the only thing that reveals the age of this thing

It was indeed a non-runner and arrived with a full wind and no slippage inside the barrel. It would run for a couple seconds given a hard shake. After a full clean I assembled it with the old mainspring (which looked fine) and it still wouldn't run. The balance was moving sluggishly but fired right up when I loosened the balance cock screw. In the end I opted to shim the bottom balance jewel assembly with some aluminium foil which seems to at least have freed the balance. Here's a picture of that assembly:

The watch now runs as well as I could ever have hoped for, and in the last week, it has consistently lost between 9 and 11 seconds per day, which means I should be able to regulate it nicely into a good timekeeper.

Here are some numbers I just recorded on a full wind:
    DD -13 s/d 315 deg 0.1 ms
    DU -5 s/d  305 deg 0.0 ms
    PR +16 s/d 264 deg 0.0 ms
    PD 0 s/d   265 deg 0.1 ms
    PL -23 s/d 265 deg 0.1 ms
    PU -4 s/d  260 deg 0.2 ms

As for why the balance was stuck, my uneducated guess would be that the balance staff was replaced at some point with one slightly too long. I've heard that you might need to bring the balance wheel into poise again when replacing the staff, lest you get varying rates in different positions. That's exactly what I'm seeing, so my tentative conclusion is that this movement went through a sloppy balance staff replacement. I'd love to hear other people's opinion on this!

With a new crystal and strap, this watch quickly became a dear friend. May it live another 60 years!

Edited January 20, 2023 by fellerts
Failed to spell "successful"

[Nucejoe]

You seem to have a good balance complete, but not a chronograde and certianly not adjusted.

I suspect the original chrono balance complete having got damaged and replaced with a non chrono one. 

Rgds