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The Seamaster Cosmic, projecting a "modern" 1970's vibe on the outside with a very traditional watch on the inside.
It's a nice looking watch, but it has had a long life & seen a lot of use. The seconds hand will turn for short spells but then stop, & it feels like something in the winding mechanism is stuck.
Let's see if we can get it fixed up & looking good...
Case has lots of scuffs, but this is normal wear
Doesn't explain how the dial got marked up, though
The Seamaster Cosmic uses a one piece case (no removable case back), & the movement comes out through the front.
The idea behind the one piece case is to (supposedly) provide improved water resistance. By not having a removable case back the watch has one less seal & therefor one less possible point of failure. In practice it doesn't work great, generates more fussing around trying to get the crystal set just right, & prevents inspection or adjustment of the movement without a complete disassembly.
Modern Omega Seamasters all now use a conventional case with the removable case back. For some collectors the uniqueness of the case design is part of the appeal for these old Seamasters (just don't go diving with it...).
Removing the hands
Dial paper underneath the hands & plastic sheet on top to protect the dial finish
(too bad the last guy didn't care to...)
Seconds hand has a little kink to it
Will (gently) try to straighten this out
Dial Side of the Movement
Dial screw to clamp the dial foot in place
Can see puddles of excess oil on top of the calendar works cap
(not supposed to have puddles of oil anywhere in the watch movement...)
Calendar disc & calendar works cap
Keyless works for winding & calendar works for advancing the calendar disc
Calendar disc
Hour wheel
Calendar works
The steel disc with the cam poking up is called the 'finger'. This is geared to come around once every 24 hours & advance the date disc.
Cannon pinion
Watchmaker Side of the Movement
Now to see about the winding & running issues...
Well that's not good...
So how much damage has been done by steel pinions turning brass wheels when the brass wheel aren't going to move?...
The brass leaves (gear teeth) are tiny, & no match for the steel pinions of the automatic winding mechanism.
Damage done, let's see how bad.
Stray case clamp freed
Winding rotor & retaining pin
Automatic winding bridge & auto-wind mechanism
The auto-wind mechanism for the Omega cal 565 exists very much as its own separate entity. No real pretense of the auto-wind function being built into the movement, this is a standalone module added on top of a standalone movement. The cal 565 was almost certainly adapted from an existing manual wind movement design to accommodate the added auto-wind module.
This works fine but adds thickness to the completed movement, as compared to a clean-sheet design where the layout of the timekeeping mechanism is adapted to also natively include a built-in auto-wind.
There's that screw
Intermediate winding drive wheel is not looking so great...
Auto-wind cap
Alternating auto-wind drive wheels
Auto-wind reversing wheel
Intermediate winding drive wheel
The intermediate winding drive wheel is what took the damage from those stray parts
The part is not salvageable, so off to the internet to try & learn the Omega part number, then off to eBay to try & source a replacement.
Sometimes you get lucky & find an all new individual replacement part in the original packaging. If that's not available, then may need to source a used intermediate winding drive wheel, or a whole used auto-wind module. If the value of the restored watch is high enough, sometimes the watchmaker is forced to go source a complete donor movement just to recover that one bad part.
In the end, this individual part was not available, but I was able to find a used whole auto-wind mechanism at a reasonable cost to serve as a parts donor.
The remaining case clamp,
screwed down where it is supposed to be
And the empty void where the loose clamp & screw escaped from
On to the escapement, & first contact with anything actually related to the timekeeping mechanism of the movement.
Balance wheel, hairspring, regulator, & balance cock
The hairspring is extremely fragile & very often difficult to replace if damaged
Can see the very small holes bored into the underside of the balance wheel. This would have been done at the factory to remove a heavy spot on the balance wheel, same principle as balancing a car tire.
Good practice to get the balance & hairspring out of the way & protected from any stray touching
Upper balance hole jewel & upper balance cap jewel
With the balance out of the way can get a clear view of the pallet & the going train
Pallet & pallet bridge
Going train bridge
Can see the progression of the going train
From right to left, the grand wheel of the mainspring barrel, second wheel (one rotation per hour), third wheel, fourth wheel (one rotation per minute), & escape wheel.
Third wheel
Fourth wheel
Escape wheel
The second wheel remains captured by the barrel bridge for now
The seconds pinion spring holds down the seconds pinion. The seconds hand is attached to the seconds pinion back over on the dial side.
Crown wheel core & crown wheel
Dual ratchet wheel, allows the mainspring arbor to wind the mainspring by either the auto-wind or via the crown
Click & click spring
The click provides the ratcheting action for the ratchet wheel & mainspring arbor, this allows the mainspring to be wound at the mainspring arbor, & at the same time prevents the mainspring from unwinding through the mainspring arbor.
Barrel bridge
This also holds the second wheel in place
Second wheel
Mainspring barrel
Mainspring barrel cap
Mainspring barrel arbor
The mainspring
The changing radius & contours of the mainspring all serve to provide a more even power discharge from full-wind to empty. The added flange on the right provides pressure, pushing the outside end of the mainspring to the inside of the barrel wall. Since this is an auto-wind movement, the mainspring needs to be protected against over-winding, hence at full-wind the outside end of the mainspring (right) will slip against the inside of the barrel wall & not accept any additional winding power. Below full-wind, the pressure & friction provided by the flange will hold the outside end of the mainspring fixed against the inside of the barrel wall, the mainspring then turns the barrel & drives the going train forward.
Back to the dial side & disassembly of the keyless works
Setting lever cap spring
Date corrector yolk
This provides the date quick-set function via the crown
Minute wheel & setting wheel
Clutch lever
Setting lever detent spring
Setting lever
Clutch, winding pinion, & winding stem
Grossly excess oil (doesn't smell great, either...)
Lower balance cap jewel & hole jewel
And that completes the breakdown.
The calendar works & auto-wind mechanism fill up a few more cubbies in the parts tray, & each section is kind of its own functional group. Add up each of those functional groups & you have yourself a complete watch.
Into the ultrasonic cleaner for two cycles of cleaning solution followed by three cycles of rinse.
Reassembly
Starting with the auto-wind mechanism
Intermediate winding drive wheel (the new one!) & auto-wind reversing wheel
Alternating auto-wind drive wheels
Auto-wind cap
Lower balance jewel assembly
The balance jewel assembly is put back together & installed without oil applied. I am then able to use the automatic oiler that meters out just the right sized oil drop through a very fine needle that passes through the hole jewel to the inside of the assembly.
It's a nice solution, but the applicator needle is very fragile (I've already broken two of these...).
Same treatment for the upper balance jewel assembly
Dial side & keyless works
Clutch, winding pinion, & winding stem
(& no more grossly excess smelly oil...)
Setting lever assembly
Clutch lever & spring
Minute wheel & setting wheel
Setting lever cap spring
Keyless works complete
Barrel bridge & click
Crown wheel assembly
Second wheel & mainspring barrel
Dual ratchet wheel
Barrel bridge assembly complete
Seconds pinion
Going train & bridge
Pallet & bridge
Before installing the bridge, can see how the pallet stones interact with the escape wheel
The moment of truth...
When the balance goes back in we get to see if the movement has life in it.
And there it goes
This can be a tense moment.
You don't know if you are heading for joy or despair, but to get there you first have to handle & fit the balance & hairspring, & that's just always going to involve risking damage to the most fragile part of the movement.
Seeing a movement come back to life after sitting silent for many years is always a good feeling for a watchmaker.
So how is it making out on the Timegrapher?...
... not so great.
Gaining a 1/2 minute per day, & these Omega movements should be capable of considerably tighter beat error.
The 0.9ms beat error is represented on the graph by the separation between the two lines. When the movement in running "in beat" then the beat error goes to 0.0ms & the two lines of the graph will seem to overlap.
Still have some work to do on the reassembly, so will let the watch run in & settle a bit before getting to deep into the timekeeping adjustments.
Calendar works
Hour wheel
Date disc
Calendar works cap
Getting close to the end
Now how are we making out on the Timegrapher?...
...better.
The running movement has had a little bit of time to settle, & just by only adjusting the beat error the timekeeping rate has been improved, as well.
Will let the now completed movement continue to run in for a while as we work on getting the case cleaned up.
The case looks rough, this Seamaster has likely served for many years as someone's everyday timepiece.
Heavy scratches throughout. If you look close, can see what looks like the radially striped graining on the top surface from the original factory finish.
Pretty well obscured now by a lifetime of battle scars.
Let's see about fixing that up...
Coarse brushing all over to give a uniform foundation for the surface finishing to follow
Medium brushing, & beginning to reintroduce the outward radial grain on the top surface
Fine radial brushing for the top surface, mirror polish for the sides & lugs
The watches I work on are very often acquired out of estate sales. The previous owner who wore & enjoyed this watch for decades has passed on, but I sometimes wonder what they would think about their old watch starting life over again, & looking like it did back when it first came to them all those many years ago.
Auto-wind mechanism
Auto-wind rotor
The completed movement
Dial
Hands
Final adjustments for timekeeping
How are we getting on with the Timegrapher?...
Bullseye
Cased up
Complete
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