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taking apart a Seiko 5Y23


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If you have hand levers (as in two separate levers not the modern presto type tool) you can remove this in a similar manner to hands, to pry it directly up, you may be able to improvise with screwdrivers otherwise, but that's the method, first time i saw this I thought it had to be pulled apart somehow like other C-clips but no, it pries up and off and is then pressed directly back down again to be refitted. 

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16 hours ago, measuretwice said:

It seems to me the brass in the centre has to come off - any suggestions on how to do so without making a mess of things?

Just don't buff the "brass" off, that would make a sure mess. :D

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progress report......

You know what the difference is between a watchmaker who knows what he's doing and me?  sore knees searching the tiled floor for parts.  An that's with a bench with glass sides back and top and the pull out catch tray.  Good news is I'm getting lots of practice and manual dexterity is improving.  I usually find the part, but this time I managed to lose the rotor when it flew off :(.  Being magnetic exacerbates the challenge, it could have stuck to so many things.

This movement is out of production.  I suppose these electronic watches are sort of a disposable consumer thing given the electronics will eventually fail, and with all the plastic they're not exactly inspiring....but hey, that one lonely jewel needed to be serviced and I'm a dog with a bone.

As it turns out the yoke is just about rusted through.  While Seiko forsakes you on the movement, the good news is both parts are still used in other watches (yoke and lost rotor) so they're available and on order.  Hopefully I can make it work.

The symptom of the watch was a jumpy second hand and not really keeping time.  Turns out there were bits of metal stuck to the rotor, no doubt the missing chunks of the yoke.  Interesting how the metal corroded in just that one spot which is an obvious stress riser.  Stress does increase corrosion in steel so it seems a bit of a design flaw....the thin spring arm could have been wider through this section.   Other than some crud from the battery, there was no other corrosion in the watch

5a0b408b19987_DSC_5242mod.thumb.jpg.95b663d41687ee402fde13814f4f17cf.jpg

 

 

 

Edited by measuretwice
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