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Is there a better way for the 7s26 barrel to be opened apart from a screwdriver?


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Not sure i would recommend that method for this kind of barrel. It may cause the lid to bubble. Same with the valjoux 7750.

The lids on these kinds of barrels can be prised off, but do not do it with a screwdriver unless you want to damage the barrel teeth.

Honestly, I find it just as easy to prise the lid away with my finger nails, although I am sure that would be frowned upon by some - never ever damaged a barrel that way.

I believe Seiko' s idea with this barrel is that it was replaced complete when servicing. I could be wrong but I do not believe a mainspring was available for this movement as a separate part - But a barrel complete rather - if my memory serves me correct. Again, I could be wrong.


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2 hours ago, Mark said:

I believe Seiko' s idea with this barrel is that it was replaced complete when servicing. I could be wrong but I do not believe a mainspring was available for this movement as a separate part - But a barrel complete rather - if my memory serves me correct. Again, I could be wrong.

No, you're correct. But one can fit a GR MS. Assuming that the existing one really needs replacement - that's unlikely on the 7S26, which can be, at most, just 20 yrs "new".

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Having said that, many are damaged by people winding the mainspring in by hand. I have seen this time and time again with the Seiko barrels just near the end where the spring doubles up.
This spring winds in reverse to the majority of movements.

Where is the OP? Has your question been answered?

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Seiko barrels such as this type should not be opened. The whole unit should be replaced. I know many parts are now obsolete.  If my memory serves me, well every 5 years. There is no proper way to open these, the less damage you cause is the safest.

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