Reply With QuoteThank you for posting! Really interesting. If I had my time again, I would love to have trained in this sort of field as it always fascinates me. Looks like a great job!Originally Posted by Horlogerie France
Repair and Servicing of Omega Military Cal 283
The owner said that the watch was not keeping accurate time and that it would start and stop. It was sent in for diagnosis and repair of the defect, along with a full servicing.
Here is an overall view when it arrived:
With the caseback removed, it doesn't look too bad and if you were buying this watch based on these photo's alone, you would not have much to worry about...but, if you look closely, you can spot a defect right away.
Look closely and see if you can find the defect, it's good practice to train your eyes to observe everything. Can you see it??
Did you notice the defect?
A closer view of the balance cock and you can see that the hairspring is bent and damaged, big glaring defect to the trained eye, but if your not looking closely, you missed it altogether...
Never trust your initial inspection
Overall the movement is in poor condition, which reveals itself as soon as you start to tear it down, it's very dirty and gummed up with old oil, the sweep seconds wheel was bent and touching the bottom of the sweep seconds pinion cock, and there was surface rust in the keyless.
The movement was completely disassembled, here is an overall view of the movement in pieces ready for the cleaning.
Hairspring defect
So why was the hairspring bent and distorted? The damage certainly didn't happen on it's own, someone carried out the rate adjustment and didn't pay attention to the regulator pin position and the effect that the regulator was having on the hairspring.
A close look at the regulator pins shows that they are not positioned properly, the pins should be perfectly parallel with each other with a small gap each side of the hairspring. As shown below, the pins are too close together, and tapered, which doesn't allow the hairspring to breath properly. When the regulator was moved, instead of the pins sliding along the hairspring surface, the regulator pins grabbed hold of the spring and the spring was bent.
Here is a close up view of the regulator pins, see how they are tapered and too close together, as well as being very dirty, you can see how the pins would grab hold of the hairspring.
BEFORE
After cleaning in the ultrasonic machine, I fixed the pins and here is what they should look like, now the hairspring can breath properly and slide between the pins as the regulator is adjusted.
AFTER
Here is a closer look at the hairspring once the balance was removed from the cock, you can see that it's not concentric.
This type of defect is repairable, however there is always a risk with a bend near the stud that the spring will break during manipulation, but that is a risk you have to take. If during manipulation the hairspring was broken from the stud, I would remove the taper pin from the stud, reinsert the spring end, and secure it once again with the taper pin.
Some careful manipulation with tweezers takes care of the defect, here's the result with it installed. The overcoil now follows the arc path of the regulator arm and the regulator pins no longer grab the spring when adjusted.
Amazing what a cleaning will do...
After the ultrasonic bath, rinses, and drying, the parts came out nice and clean.
Here is the sweep seconds wheel and pinion, cleaned, oiled, and with the wheel installed level with the bridge.
Before
After
Keyless works looks much better after clean up.
Before
After
Before
After
After assembly and oiling, a slight adjustment of the beat was needed. Adjusting the beat on a fixed stud design has to be done by removing the balance from the balance cock, then you move the hairspring collet on the balance staff, reassemble the work, and put on the analyzer to see if you got it right, that being direction of adjustment and amount. Along with the beat adjustment, the hairspring needed a slight adjustment in the flat, and the rate adjusted. I timed and adjusted the movement in all 5 positions, and the movement ran well within specifications.
Thank you for reading.
Rob
Thank you for posting! Really interesting. If I had my time again, I would love to have trained in this sort of field as it always fascinates me. Looks like a great job!
Great stuff, as always - thanks for posting.
These threads are really interesting, thanks for posting.
Fascinating.
I love these posts.
As always, a delight. A master craftsman at work. What this illustrates is how vintage watches can be repaired and kept going for many decades. I just hope that there is enough decently paid work for watch repairers to allow a new generation to come along. Without them, the whole hobby would wither and die.
Which, incidentally, is why the big companies should stop the practice of refusing to supply parts to small independents who haven't danced to their tune.
Fantastic post.
Very interesting. Makes me want to have a poke around with a couple of cheap broken watches I have in the drawer!
Thanks for posting, Rob - wonderful stuff as always and a real insight for me (as a vintage enthusiast) into what horrors may be lurking in a movement that on casual inspection looks reasonably clean!
Excellent read.
Thanks for these very interesting posts.
looking forward to the next one.
Great post :)
Thanks for taking the time to show us.
I am always surprised how dirty the movement gets!
Is it down to too much lubricate, parts wearing against each other, moisture getting in or all of these?
Have you ever lost any small components down that hole in your bench? In my experience if it's possible for parts to end up in the most awkward place they will
Again, interesting and educational. Ta.
F.T.F.A.
The before and after pictures are stunning! What an amazing transformation.
As usual a great read. What camera do you use?!
A great read... more please!!
Very pleased to say I did spot the bent spring in the photo before scrolling down to see what the defect was! These are always fascinating to read so thanks for sharing :)
Thanks for the positive feedback.
An old Olympus with a macro lens.
Not yet, I work on the matt not on the wooden section in the photo.
Yes, all of the above.
In order of relevance, these are the biggest problems with movements:
#1 Botched workmanship from so called 'watchmakers'
#2 Lack of regular servicing
#3 Dirt and moisture ingress
Well unfortunatly that decision by the Swiss has already been made. It won't be the end of the trade of watchmakers, but eventually the same result for the Swiss as happened in the 1970's when the Swiss were beaten down by the Japanese makers (Seiko, Casio, and Citizen). It's already started where the Japanese are filling the void...
The topic has been discussed at length, so I won't add anymore, but to answer your question, I do think the future is bright, and so does the BHI with their new British Horological training school under the funding of the HLF...
Excellent, you have a good eye for detail!
Very enjoyable reading. Please keep posting.
Thank you.
I have set aside time every Friday morning for writing and posting this type of short article, so hopefully members will find them interesting and useful.
Rob
Good news, these are fascinating and a welcome departure from some of the threads in WT
Where in Charente are you?
Just south of Angouleme...Good news, these are fascinating and a welcome departure from some of the threads in WT
Where in Charente are you?
A great read, thank you.
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Real good educational post. Thank you for sharing.
Lovely! I'll be staying in Triac in September for the annual pilgrimage to the Circuit de Remparts
I love these old Omega movements, I`ve worked on a few and they always seem to run well after a bit of care and attention. Truing up the hairspring and getting the thing back in beat can take some time, that's the only thing I don`t like about them. Definitely built to last!
Paul
nice.
I'm really enjoying these posts, thank you Rob. As someone who has benefited from your amazing skills it's lovely to see the work you've done on other watches too.
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Top stuff as ever, Rob.
Nice to hear you’re willing to set aside time to provide us with more insights as to what you get up to each week.
love these posts, factual with photos, for the lesser men among us to understand (like me)
thanks
Thank you for your contributions. They are very entertaining and educational, a balancing act not easily achieved.
Thanks also from me, I really appreciate you taking the time to write these informative commentaries.
Very nice! Somebody will be happy to have his '53 FA back in service. Thanks very much indeed for posting this, I enjoyed it a great deal.
Very enjoyable.
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