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Cheap Chinese Seiko (7S26 C) balances


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All,

 

Has anyone had experience of fitting cheaper Chinese (£5ish) balance assemblies in this case the 7S26 C variation and been successful?

 

I went for the cheaper option as the OEM variation seems to be quite difficult to obtain. My experience hasn’t been great, having fitted 4 of the same variation with no luck, for the following reasons:

 

* 2 x wheels were bent at the pivot, one was so extreme it wouldn’t spin at all, whilst the other wouldn’t regulate due to being out of balance.

 

* one regulated ok but later become detached from the stud and therefore stopped completely.

 

* and the last and most recent set up really well +6 s/d and 0.4 beat error and a good trace. After three or so hours jumping to 9.5 beat error and +25ish s/d ish. I left it over night to later find that the hairspring had changed shape jumping to +600ish average and jumping all over the place!

 

It seems like the best of a bad bunch have springs that are too soft?!? Luckily the sellers have been great and send replacements or given a refund so no financial loss, just annoying that my watch is still out of action.

 

I’m no expert, but had some experience with balances as well as regulating with some success with this being a different league.

 

This seems to be an area to avoid!

 

It would be great to know if anyone on here has had any similar stories.

 

Regards

 

Carl

 

 

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Never ordered such parts but I did see them around on chinese websites and I actually wondered whether they're OK.

From your experience they sound like utter crap. Hoping others can chime in... I think I've seen some for ETA as well. I wouldn't be surprised if they were the same thing (more or less).

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Never ordered such parts but I did see them around on chinese websites and I actually wondered whether they're OK.
From your experience they sound like utter crap. Hoping others can chime in... I think I've seen some for ETA as well. I wouldn't be surprised if they were the same thing (more or less).

I’ve even repaired a couple of fake (Turkish) Rolex’s with the cheaper movement and they went great, although I managed to source second hand parts and set up really well. These are not even close!


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I have heard that there are the cheap crappy Rolex fakes and then there are those that have genuine parts in them or have parts made by people that have actually worked for Rolex, possibly, with professional equipment. Coincidentally it was also Turks.

I don't know how yours was but I imagine that there are some out there that are really good and they sell for quite a few hundred $ so I'm not surprised that these Chinese parts are really bad.

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1 hour ago, carlos123 said:

Has anyone had experience of fitting cheaper Chinese (£5ish) balance assemblies in this case the 7S26 C variation and been successful?

I was wondering myself and will jave to experiment. Good results from topic below

 

1 hour ago, carlos123 said:

I went for the cheaper option as the OEM variation seems to be quite difficult to obtain

You mean genuine Seiko? Easy to get from Cousins, but much more expensive.

1 hour ago, carlos123 said:

* and the last and most recent set up really well +6 s/d and 0.4 beat error and a good trace. After three or so hours jumping to 9.5 beat error and +25ish s/d ish. I left it over night to later find that the hairspring had changed shape jumping to +600ish average and jumping all over the place!

Check because this is a typical symptom of the HS rubbing somewhere

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  • 2 weeks later...

Sounds to me the most likely issue is that the adhesive used to attach spring to stud isn't up to snuff. After removing the last balance, the one you mentioned the hairspring spontaneously deforming, do you still observe the hairspring itself to be out of sorts? Or is it more or less original shape? And if the hairspring is attached at the collet with adhesive as per seiko, chances are it would be with the same adhesive. The adhesive at the stud can be replaced with shellac easily enough, but the procedure isn't so manageable at the collet. 

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  • 2 weeks later...

I finally got round to fitting a “proper” balance and it works great! I was a little worried at first as the timegrapher was showing snow, but managed to regulate it to at one point 2s/d and BE of 0.1 - so well happy [emoji2]

The moral of the story if don’t be tight and get cheaper OEM parts.... [emoji2357]

Thanks for all your input[emoji106]

Regards

Carl


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