1950s Seiko Marvel Balance Staff

[AndyGSi]

I think this is probably the part you were looking for but as it's a non standard Seiko Part Number there's no information on it.

Maybe you could compare details with the Laurel @Embezelled has.

[Embezelled]

I doubt that I know enough at this stage of my journey to impart anything useful. I have the Laurel here, with (finally) the back off. 

I also looked on Yahoo Auctions, there is a seller at the moment with what they've listed as a Seiko Marvel balance staff, but I don't know if it's the right part for your watch. It seems you need the whole balance anyway, and I'm not seeing any of those for sale. There is a very trashed looking Marvel from another seller that might suit as a donor unit, but no photos even with the back off, and the crystal is missing. It doesn't look promising: the dial is severely corroded, so useful internal parts might not be salvageable. 

https://auctions.yahoo.co.jp/jp/auction/w1112646076

https://auctions.yahoo.co.jp/jp/auction/o1185016360

Edited 9 hours ago by Embezelled

[nevenbekriev]

On 5/16/2025 at 10:51 PM, MikeEll said:

Brand new from Cousins.  The balance wheel is a totally different size, too big to fit the movement.  Tried transferring the hairspring to the original balance, hence the rapid gain.  Yes, all screws fitted and the balance setup properly in beat.

Mike, You have the correct hairspring, only needed is to replace it's collet. So suitable collet is needed. I would not use the one from the new spring, as it can be backup variant. But it is not a problem to source a collet with the proper size (at least if one has piles of movements for parts).

[AndyGSi]

1 hour ago, Embezelled said:

I doubt that I know enough at this stage of my journey to impart anything useful. I have the Laurel here, with (finally) the back off. 

Photos and dimensions of the balance may help resolve if it's the same as the Marvel.

[Embezelled]

Rear of the Seiko Laurel. As best I can measure it with a caliper, the outer diameter of the balance wheel is 11 mm.

[Embezelled]

This is the same image, cropped in.

 

[MikeEll]

16 hours ago, JohnR725 said:

Thinking of best fit did we ever look at fingerprinting this movement?

....

 

 

I've done some serious digging trying to find information.  My father is still in business as a watchmaker at 81 years old, and he has bookshelves full of old service data and parts lists, including Seiko.  I went through most of it and could find no information on the Seikosha 17 jewel movement.  I guess its just one of those awkward ones with scarce information available.  Its a shame really as many of the parts are still available for low cost, we just cant find 'em

4 hours ago, nevenbekriev said:

Mike, You have the correct hairspring, only needed is to replace it's collet. So suitable collet is needed. I would not use the one from the new spring, as it can be backup variant. But it is not a problem to source a collet with the proper size (at least if one has piles of movements for parts).

I've never attempted to replace a hairspring collet, but I'd be interested to try just to develop the skill.  I have a microscope and suitable tweezers, might give it a go.  How are the collets even fitted to the spring?  I'd assume its press fitted around the end of the spring.

Update *** - I've just had one under the scope for a closer look.  There's a slot across part of the collet.  The spring seems to be fitted to the slot and then the slot closed up around it.  Does anyone even supply hairspring collets?... Wow, seems you can buy them on Cousins, who knew :-).  

 

Edited 4 hours ago by MikeEll

[AndyGSi]

So how does your balance in the Marvel compare with the one in the Laurel.