1950s Seiko Marvel Balance Staff

[rustyscoot]

Hi all, I wonder if anyone may be able to help with identifying / sourcing a balance staff for a 50s Seiko Marvel please?

I don’t believe that there is a calibre number for this movement, it is known as the Marvel. It is an 11.5 ligne movement. The Lord Marvel is a descendant but not interchangeably so.  I managed to acquire a Bestfit 1870 staff which is a fair bit too short but does have a lot of features going for it. The table height appears good as does the roller seat diameter and most probably the collet. It is a friction fit type staff and my balance was marginally too loose on it to be secure. I will upload a pic with measurements plus Bestfit and Ronda keys. I suspect the correct staff is at least 0.1/0.2mm longer than the 1870. I do have a Ronda staff for a later model, I forget which, that I might be able to remove the rivet thus adapting it to a friction fit to see if that will work. As you can imagine if somebody is familiar with these early Seikos and can jump in with an educated “Yep you need a blah blah blah for that one” it would be a much better outcome than a modified staff. I am starting to suspect that fate of this watch is to be dismantled and parts sold to help prevent further watches from a similar demise. But as a last resort I kindly ask if anyone is familiar with these and if they have any leads. 
One more point to note there is no semi circlular cut out by the balance at 10:00 ish nor are there two studs visible on the balance cock on my movement unlike some of the similar looking movements I have come across during my research.

Thank you for your time.

[clockboy]

Welcome to the forum, enjoy. I use balancestaffs.com.

 

https://www.balancestaffs.com/seiko.php

[rustyscoot]

2 hours ago, clockboy said:

Welcome to the forum, enjoy. I use balancestaffs.com.

 

https://www.balancestaffs.com/seiko.php

Thanks for your reply. Unfortunately I don’t think Seiko were on Ronda’s radar at the time. Bestfit, Ronda and DCN do not appear to have manufactured a staff for this calibre. I would suspect I’m looking for a Seikosha manufactured part. Balancestaffs.com is a great site and a lot more user friendly than the Mid 60s manuals. Although in favour of the manuals, when comparing prints of 50s to 60s manuals you get to see how Ronda re-used their codes as staffs went obsolete. And of course you can’t beat the smell of vintage paper!

[RichardHarris123]

Hello and welcome. 

[JohnR725]

7 hours ago, rustyscoot said:

Seiko Marvel

the problem with the parts books like bestfit is the watch had to be made in sufficient quantities exported from the country of origin that somebody would be concerned about having a spare parts available for it.

then for instance if you had the bestfit book and look up Seiko they do actually list the named calibers just not yours. Then what shouldn't do is go find the section of balance staffs listed by size and see if you can find the staff that's very close to what you're looking for. Seeing as how this was their first in-house movement it's hard to tell whether any of the parts would migrate to other watches or whether everything was unique on this watch.

Then what's interesting about yours is the spring holding in the jewel for the balance is different than what I'm seeing. Neither seeing some with no spring at all or Seiko's standard spring. Which there very proud of and they put that on the dial. None of which helps you get a balance staff though.

 

oh and here's a bit of the history on your watch

https://corporate.epson/en/about/history/milestone-products/1956-6-seiko-marvel.html

[rustyscoot]

43 minutes ago, JohnR725 said:

the problem with the parts books like bestfit is the watch had to be made in sufficient quantities exported from the country of origin that somebody would be concerned about having a spare parts available for it.

then for instance if you had the bestfit book and look up Seiko they do actually list the named calibers just not yours. Then what shouldn't do is go find the section of balance staffs listed by size and see if you can find the staff that's very close to what you're looking for. Seeing as how this was their first in-house movement it's hard to tell whether any of the parts would migrate to other watches or whether everything was unique on this watch.

Then what's interesting about yours is the spring holding in the jewel for the balance is different than what I'm seeing. Neither seeing some with no spring at all or Seiko's standard spring. Which there very proud of and they put that on the dial. None of which helps you get a balance staff though.

 

oh and here's a bit of the history on your watch

https://corporate.epson/en/about/history/milestone-products/1956-6-seiko-marvel.html

You make a good point. The calibres listed in Bestfit / Ronda are 60s calibres. The world still has an affinity to the mid 60s divers suggesting Seiko became familiar to the world at that time. Hence why I’m hoping someone has knowledge of Seikosha parts rather than shooting blind modifying a Ronda 5347 to “fit”.

Thank you for the link.

[Nucejoe]

An article on lord marvel which also covers the exact variant you have.

https://adventuresinamateurwatchfettling.com/2020/04/04/origin-of-the-species-a-seiko-marvel-from-1956/

Good luck

[rustyscoot]

10 minutes ago, Nucejoe said:

An article on lord marvel which also covers the exact variant you have.

https://adventuresinamateurwatchfettling.com/2020/04/04/origin-of-the-species-a-seiko-marvel-from-1956/

Good luck

Thanks I know it well. Luckily for him he had an OK balance which obviously makes repair significantly easier. I may have a lead on a Japanese source of parts.

 

Thank you to all.

[nevenbekriev]

I guess You are not sure about the exact lenght of the staff needed? You have only the old one which is broken so You can not measure it?

There is simple way to exactly measure the needed lenght. I will explain if needed. Have in mind, that in shock proof movement staffs there are a lot more dimensions to be compared than this A,B,C,D before making conclusion that the staff will fit. That's why it is making new staff much more secure choice than finding similar one and trying to modigy it. Unless it is bigger in all sizes and used as a stock material...

[JohnR725]

On 1/26/2024 at 5:49 AM, Nucejoe said:

An article on lord marvel which also covers the exact variant you have.

https://adventuresinamateurwatchfettling.com/2020/04/04/origin-of-the-species-a-seiko-marvel-from-1956/

one of the minor annoyances with the article is he gets a balance complete from  cousins and conveniently doesn't tell us which one it is. I always find it interesting rewrite a fairly detailed article with lots of pictures of naked movements and gears and then you just don't tell us the actual part numbers just in case somebody might like to follow in your footsteps

On 1/25/2024 at 7:04 PM, rustyscoot said:

Bestfit 1870 staff which is a fair bit too short but does have a lot of features going for it.

11 hours ago, nevenbekriev said:

I guess You are not sure about the exact lenght of the staff needed?

actually I'm not sure about the dimensions he gave us dimensions of the image up above and the helpful link to the article above is it's helpful because we had no part numbers we don't have anything to reference the other Seiko staff that is mentioned with vintage Seiko's is 2009 and it's much longer than his dimensions which is why I'm not sure about his dimensions.

so here's where to get an interesting problem the size the 1870 still longer than the suggested size in the measurement.

which possibly says the 2009 is the correct size staff. As it's the recommended staff for most not all but most of the vintage Seiko's at that time with shock protection with 1870 is for non-shock protected.

But those dimensions are still considerably longer then what he has for his suggested staff length.

 

 

 

[rustyscoot]

5 hours ago, JohnR725 said:

one of the minor annoyances with the article is he gets a balance complete from  cousins and conveniently doesn't tell us which one it is. I always find it interesting rewrite a fairly detailed article with lots of pictures of naked movements and gears and then you just don't tell us the actual part numbers just in case somebody might like to follow in your footsteps

actually I'm not sure about the dimensions he gave us dimensions of the image up above and the helpful link to the article above is it's helpful because we had no part numbers we don't have anything to reference the other Seiko staff that is mentioned with vintage Seiko's is 2009 and it's much longer than his dimensions which is why I'm not sure about his dimensions.

so here's where to get an interesting problem the size the 1870 still longer than the suggested size in the measurement.

which possibly says the 2009 is the correct size staff. As it's the recommended staff for most not all but most of the vintage Seiko's at that time with shock protection with 1870 is for non-shock protected.

But those dimensions are still considerably longer then what he has for his suggested staff length.

 

 

 

The 2009 has a rivet and is not a friction fit. Plus the roller seat and collet diameters are too small and therefore it can not be the correct staff.

It is probably closer in length though. With the 1870 measuring 317 and me estimating it to be a tenth too short.

 

 

 

 

 

[Nucejoe]

8 hours ago, JohnR725 said:

actually I'm not sure about the dimensions he gave us dimensions of the image up above and the helpful link to the article above is it's helpful because we had no part numbers we don't have anything to reference

Right, 

 So far as I know which is not much, all Seiko Marvels were powered by calib 5740  with three variants A, B and C .

Seiko Marvel 5740A  which beat 18000 per/ hour.

Seiko Marvel 5740B which beat 21600 per/ hour.

Seiko Marvel 5740C   which beat 36000 per/ hour.

Just by the looks of bridge layout I say this is 5740A, to make sure OP can count gear teeth, pinion leaves to calculate the beat. 

I don't know which staff fits which calib.

Hope this helps

[nevenbekriev]

I would advice You to use micrometer to measure the distance between tops of the cap jewels and subtract the hights of the both cap jewels from the result. Thus You will have the correct staff lenght.

[rustyscoot]

On 1/28/2024 at 3:36 PM, Nucejoe said:

Right, 

 So far as I know which is not much, all Seiko Marvels were powered by calib 5740  with three variants A, B and C .

Seiko Marvel 5740A  which beat 18000 per/ hour.

Seiko Marvel 5740B which beat 21600 per/ hour.

Seiko Marvel 5740C   which beat 36000 per/ hour.

Just by the looks of bridge layout I say this is 5740A, to make sure OP can count gear teeth, pinion leaves to calculate the beat. 

I don't know which staff fits which calib.

Hope this helps

They are Lord Marvel calibres from a few years later. They are descendants of this calibre but are not interchangeable.

[rustyscoot]

Thank you all for your input. It seems the answer lies with the Moeris 10.5’’’ staff with this particular calibre. I will need to slightly reduce the thickness of the friction fit / collet seat.