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Swatch Eta 2840 Walkthrough


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Swatch ETA 2840 Walkthrough

Based on a summary research, this movement is very similar to the ETA 2801 et al family. Nevertheless, Ranfft doesn't list it as part of that family and instead says it is made only for swatch watches. All in all, the movement comes encased in a laser sealed case made of either plastic or metal. They are supposed to be throw away/disposable watches not meant to be serviced. The plastic crystal is supposed to be buffed when scratched, not replaced, since, again, it is laser welded to the plastic case.

The irony models usually have a pressure sealed backs, being reinforced with a metal ring at this area, and can be opened. Due to the nature of those cases, movements can be found in almost pristine condition once the case is opened. That is, they mostly fail at the lug area where it attaches to the band (plastic breaks).

At times, the case ruptures and then the above does not apply. Also, there exist a belief that in order to fix something in these watches we need to break something to get at it. Example, break the crystal and cut the stem, to get to the movement. Again, it is not necessary in some models.

 

@My friend Colin: If you are reading this, it is with great pleasure I will be using the cases you so kindly gave me. I know it has been a while but for a busy hobbyist like me, things take time...but they get done...eventually! Always a pleasure to say hi!

 

So without much ado here is the disassembly of a Swatch ETA 2840:

 

Swatch ETA 2840 Walkthrough.pdf

 

To be continued.....

 

Due to time constraints, I had to do a pdf for faster download. Hope it works well.

 

Cheers,

 

Bob

Edited by bobm12
Pdf update
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Enjoyed that.  Whats going on with that Intermediate wheel?  Is this coated with some kind off life long graphite paste?

 

Where did you get that Kif tool?  I recently purchased one from eBay, but not as pretty as yours :)

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Where did you get that Kif tool?  I recently purchased one from eBay, but not as pretty as yours :)

Is that your tool fetish kicking in again Micky? :D I think the tool will be the same as yours, it's just that Bob has his held in a pin vice.

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@My friend Colin: If you are reading this, it is with great pleasure I will be using the cases you so kindly gave me. I know it has been a while but for a busy hobbyist like me, things take time...but they get done...eventually! Always a pleasure to say hi!

 

Cheers,

 

Bob

 

 Message received. Thanks,

Colin.

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Is that your tool fetish kicking in again Micky? :D I think the tool will be the same as yours, it's just that Bob has his held in a pin vice.

 

Yup, guilty as charged.  Here's the one I purchased from a US eBay seller..

 

22360052580_e3355027e2_c.jpg

Edited by SSTEEL
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@Colin: Most welcome, Colin!

 

@Micky: Absolutely Micky, those are the cousins and/or ofrei offerings....probably ofrei in my case and yes, as Geo said, held in a pin vise. The little springs are a pain, once they ping away it is bye, bye...or maybe buy, buy! :)

 

Also, what you noticed on the intermediate wheel is rust! I was able to clean it up a bit but chances are it has to be replaced. I'll work on it a little bit more today, time permitting. I can't explain it other than thinking about chemical interaction between the lubricant and the metal since everything else is ok...no more serious rust. Even if the case is compromised, it is not very likely that whatever rusted the wheel only affected it and not the rest of the watch. Any ideas and/or solution to this mystery is welcome though! :)

 

By the way, I haven't tried the tea method of de-rusting. What kind of tea is the best and how do we use it? I wonder if anyone out there has been particularly successful with this method and can outline the proper/fastest way to it.

 

I have used the bergeon stuff and the vapo-rust. The former is like Chlorine or Alum but milder (sometimes it works and sometimes it won't, at extremes and is good to stain everything black), the second one eats the kiff springs and erodes other parts depending! So here I am again, finding a solution for a good and mild de-rusting agent! I had a bad rusted Swatch movement (one of the lot) that was so rusted I immersed it, completely, in vapo-rust but I lost all the kiffs. The parts that were badly rusted didn't really de-rust and some other stuff came out separate, i.e. staffs and wheels came apart, etc. I would not recommend it to anyone.

 

In any case, it is fun so far!

 

Cheers,

 

Bob

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Hi guys,

 

Thanks Geo, excellent picture, just like my tool!

 

@rogart: The dials are great, rogart, thanks for the pictures. I believe one of my movements has a date ring, must be an ETA 2847 or something...still in the watch though.

 

@jaycey: Here goes my star explanation, hopefully I'm making some sense! There is a plastic ring (it is sectioned, narrowly, at one end to allow for the stem to have free passage) that surrounds the movement. It is rather thick and fits the cavity in the case in one position, then it is turned 1/4 clockwise or so to secure it. To free the movement the opposite has to be done, then, by grabbing each end of the cut section we do as if to straighten the ring effectively releasing the movement...did I confused you still more? :) I can't take a picture now but I'll post one as soon as I have an opportunity.

 

Cheers,

 

Bob

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Hi guys,

 

Thanks Geo, excellent picture, just like my tool!

 

@rogart: The dials are great, rogart, thanks for the pictures. I believe one of my movements has a date ring, must be an ETA 2847 or something...still in the watch though.

 

@jaycey: Here goes my star explanation, hopefully I'm making some sense! There is a plastic ring (it is sectioned, narrowly, at one end to allow for the stem to have free passage) that surrounds the movement. It is rather thick and fits the cavity in the case in one position, then it is turned 1/4 clockwise or so to secure it. To free the movement the opposite has to be done, then, by grabbing each end of the cut section we do as if to straighten the ring effectively releasing the movement...did I confused you still more? :) I can't take a picture now but I'll post one as soon as I have an opportunity.

 

Cheers,

 

Bob

 

Thanks Bob,

 

You have confused me slightly because I asked how the dial attaches to the movement, but you have given a excellent explanation of how the movement is secured!

I ask because I don't see any fixing points for dial feet?

 

I am guessing though, by your explanation, that the dial and movement is secured using some sort of locking ring method that you explained above. Correct?

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No jaycey, and sorry for the misunderstanding, the dial seats on the ring I described and is pretty much lose but partly supported by the case also. At least that's the way so far with those broken watches I'm practicing on. In fact, the dials are not exactly a full solid circle but more like a ring. You can see most of the movement from the front as if they were -- but they aren't -- skeletonized. So, the dial is only minimal or a designer's type.

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