Ladies Omega Power reserve

[dnhb]

A friend has asked me to look at her Omega watch saying that it seems to keep stopping. It runs to time on the bench for 12-13 hours: is this a normal power reserve for this size/type of watch? (it's 2cm+ diameter but no indications of the model are visible - I daren't try opening it as it looks like it needs a proprietary tool to do so)

[RichardHarris123]

We need the caliber to know the power reserve.  If you're not willing to open it, how can you help her?

[Nucejoe]

Jax tool would work just spread a plastic sheet on the case back.

Perhaps cal 630.

Twelve to thirteen hours power reserve is low.

[Knebo]

Yes, Jaxa tool or the rubber ball. 

Calibre 630 seems plausible. I recently fixed a 625 (similar to 630, but without centre seconds) and the size/design are similar. 

12-13 hours isn't enough, without question. The cal 630 should do 30h and I believe that's pretty much the lowest you'll find. 

 

 

[dnhb]

On 7/22/2024 at 5:49 PM, RichardHarris123 said:

We need the caliber to know the power reserve.  If you're not willing to open it, how can you help her?

At this stage I think I can best help her by not opening it (I don't want to scratch the back for a start !) & passing on the advice on offer here!

On 7/22/2024 at 7:14 PM, Nucejoe said:

Jax tool would work just spread a plastic sheet on the case back.

Perhaps cal 630.

Twelve to thirteen hours power reserve is low.

Thanks, that's helpful.

[mikepilk]

Omega spec sheets for cals 620/625 show a power reserve of 30h. 

[dnhb]

On 7/22/2024 at 7:14 PM, Nucejoe said:

Jax tool would work just spread a plastic sheet on the case back.

Perhaps cal 630.

Twelve to thirteen hours power reserve is low.

Thanks, that's helpful.

In parallel with seeking advice - and thanks for all the responses - I've been recording the watch power reserve each time I've wound it and over 5 days that has doubled from ~ 13 hours to 26 hours, presumably as the watch has 'run in', it not having been used for some time. During this monitoring period I was thinking a new mainspring might be required but I think the fact that it now runs for more than a day might makes it once again a practical timepiece for my friend.

[mikepilk]

1 hour ago, dnhb said:

I've been recording the watch power reserve each time I've wound it and over 5 days that has doubled from ~ 13 hours to 26 hours, presumably as the watch has 'run in', it not having been used for some time. 

Sounds like it needs a service.

1 hour ago, dnhb said:

During this monitoring period I was thinking a new mainspring might be required 

You don't usually need to change the mainspring.  I'm currently testing a cal 625 I just serviced. The hairspring looked a little 'tired' in the centre coils, but I thought I'd try it.  It's giving a healthy 290° amplitude (240° after 24h) and power reserve of about 40h (spec is 30h). 

[dnhb]

On 7/27/2024 at 5:14 PM, mikepilk said:

Sounds like it needs a service.

You don't usually need to change the mainspring.  I'm currently testing a cal 625 I just serviced. The hairspring looked a little 'tired' in the centre coils, but I thought I'd try it.  It's giving a healthy 290° amplitude (240° after 24h) and power reserve of about 40h (spec is 30h). 

The fact is I'm at a very early stage in my Watch/Clock tinkering and don't have the confidence to address a relatively high-end marque that isn't mine when it can be 'improved' sufficiently without any risky intervention. The owner now feels that the watch is a practical timepiece for her as I've shown it didn't just 'stop running' randomly & was thus unreliable which had been her impression leading to it being unused for some time & why she asked if I could do anything to help. I will, however, pass on your comment that it could nonetheless do with a service. 

[mikepilk]

3 hours ago, dnhb said:

The fact is I'm at a very early stage in my Watch/Clock tinkering and don't have the confidence to address a relatively high-end marque

Wise words. So many think it will be easy, and end up damaging nice watches (despite warnings). The Omega 620/625 are nice simple movements, but just their small size makes them fiddly for beginners. Good luck with your tinkering. One day you will have no problem servicing such movements.