Cal 503 frustrations

This was my first ever vintage watch (crap photo, sorry)

i bought it (massively overpaid) at a bricks and mortar store after I got my first bonus.

I hadn’t worn it in years and years (there was a crack in the crystal, and kept putting off getting it replaced). I finally sent it off to service and replace the crystal, only to be told it looks like the movement can’t be fixed

The movement is mostly fine with one major caveat. The balance itself needs to be replaced. Positional timekeeping will never be in spec without doing so. The hairspring has lost its tension and the balance pivots are worn. This would likely be down to long periods without maintenance. At the moment there are no balances on eBay and they have been NLA from Omega for quite some time. As much as I’d like to strip it down completely and clean it, I know it will be a losing battle to get it to keep time afterwards. When the balance was still available from Omega they were $680. It’s anyones guess what one might cost on the secondary market, they are rare though. The only thing to do is to keep looking in the hope that one turns up.


Based on that assessment, I’m guessing the movement was already in a bad way when I bought it about 10years ago. And in fact, in retrospect, it never kept good time.

So, now I’m on the hunt for a donor movement or at least a balance.

All watchmakers have different skills and, if you do a lot of modern calibres, it's often easiest and cheapest to replace the complete balance than try and solve an issue with it. An ETA 2892 balance complete is under US$100 depending on the specification (for example, chronometer).

It's unusual to need a complete balance on a vintage watch. I see two issues are mentioned (there may be others that we don't know about):

balance pivots are worn: Easy one first - the pivots can be polished with a Bergeon 5482 tool and this will bring back slight flatting and I do this every week. If not enough, it's in the Jacot to polish the pivots properly. And then, change the staff for a new one when all else has failed, which only happens a few times a year for me. Staffs for the 500 series are available for under US$100.

The hairspring has lost its tension: I'm not sure what is meant by this as it is not likely that the hairspring elastic modulus has changed. So, it sounds like the balance is vibrating at the completely the wrong rate and this was a quick explanation. This is often due to someone having shortened the hairspring after breaking it close to the stud but may just be a damaged hairspring. Hairspring damage is often recoverable even when it looks hopeless. These are screwed balances so, within reason, you can add washers to slow the rate or reduce the screw masses to increase the rate if that is the issue.

It would be worth getting an opinion from a different watchmaker as, like I say, everyone has different skills so it may be that the watchmaker you are using doesn't want to get involved in something that will just take a lot of time and be difficult. We all turn work down.

Good luck, Chris

According to Jules Borel.

Balanced was used in the 490, 491 and 500 - 505

I have 3 - 490, 502 and 503

However. Guy on Ebay has one for about $75.00 including s/h and a little plastic holder

https://www.ebay.com/itm/OMEGA-490-...336691&hash=item3d9c598061:g:lhwAAOSw5M9ajisb

Regards

DON