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Mido Ocean Star Powerwind oscillating weight and post


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Another rookie mistake

I serviced this watch probably four months ago and put it on the autowinder (which some people have an aversion to!!).  While it timed out well on the bench, it was randomly losing lots of time.  It took a while for me to get the courage to open it up again--it is a front-loader requiring a special tool to remove the crystal...I have it...but it is a little scary to use.

Anyway, today, I opened it up and decided to check the upper and lower balance jewels.  The were fine, but I cleaned and oiled again.  Under the microscope, the pivots were perfect.

Then, by happenstance I noticed that the oscillating weight dragged against the balance.  Oh my!  When I removed the weight to check the post...it just came out!  I went back and looked at my disassembly pictures, and it had not come out during teardown.  A real mystery. How could this be...I will never no.

Fortunately, when I embarked on this job, I immediately found a donor on ebay...just in case.  Hey--this belongs to my old boss...the guy that hired me out of college some jillion years ago...a very demanding person.

Now I am waiting for the watch to run down and I will replace the bearing plate for the oscillating weight.

Is this a common thing for automatic winds?

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7 minutes ago, LittleWatchShop said:

Was it originally pressed in?
Was it staked in?

These two things are, as someone say, "the same difference" 🙂

'

Quote

Was it glued it?

Glue has (almost) no place in watchmaking.

Edited by jdm
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37 minutes ago, LittleWatchShop said:

Well, what I meant was.  Put in and the kind of rivited from the other side.  I rather doubt that, but I am grasping at straws here.

Anyway, I hate this watch for several reasons.

Besides the mentioned LWS or were they enough. I would have thought the post was originally pressed in. Is it possible that the continuous winding from the watch winder in the same planes was too much and encouraged premature rotor bearing wear then causing an uneven pull on the post to eventually loosen it from its seating 😥.  Maybe a good reason not to use auto winders.

1 hour ago, jdm said:

These two things are, as someone say, "the same difference" 🙂

'

Glue has (almost) no place in watchmaking.

🥱 🤐

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20 minutes ago, Nucejoe said:

Whatelse is there to wear out or break, its either the post or the bush in rotor. 

Seen broken ones quite often, not much can one do other than to repair or replace the broken parts.

My issue is that I just have not seen enough of these...experience counts!

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This type of oscilating weight is heavy enough to easily turn on the post even if unlubed, which causes wear on the post and the bushing. Thats another culprit with this design.

  In F4007N variant FELSA put jewels in the rotor instead of brass bushing, which came in 30 and 41 jewels version, those are real good winders, one would expect to see a culprit with the jewel breaking too often but I am yet to see a broken jewel in said  rotors.  

Best wishes

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17 hours ago, LittleWatchShop said:

Well, what I meant was.  Put in and the kind of rivited from the other side.  I rather doubt that, but I am grasping at straws here.

Anyway, I hate this watch for several reasons.

So nice when someone points something out that isn't especially helpful dont you think LWS . 👏

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39 minutes ago, Neverenoughwatches said:

So nice when someone points something out that isn't especially helpful dont you think LWS . 👏

Oh, @jdmcan be snarky from time to time, but I love him.  He has helped me a number of times!  And, it would be really hard for anyone to offend me on this forum anyway--it is my favorite hangout!

 

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2 minutes ago, LittleWatchShop said:

Oh, @jdmcan be snarky from time to time, but I love him.  He has helped me a number of times!  And, it would be really hard for anyone to offend me on this forum anyway--it is my favorite hangout!

 

Its mine too if i had to be truthful. Ok It does wind me up though.  I dont feel it is necessary, its no effort to be kind and considerate,  just nice even, if neither of those then only civil at a push would be better than hints of sarcasm. Some folk would be far better individuals if they just chilled out and removed that wooded implement from up their waste disposal orifice. It means i can spend a lot more needed time learning and repairing instead of me having to mention it every time i see it 🤦‍♂️

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