[Daver]

Can anyone help re replacement mainspring for Cal 6139B (17J) as originals seem unobtainable. Seiko part no 401616, barrel+arbor assy 205613, arbor 213612. The barrel/arbor have same Seiko no for Cal 6106A (base cal for 6139B) as well as 6106B (also 6139A) but the mainspring is 401615 (which I can source). How does the 401616 differ from the 401615 as they appear to fit into the same barrel/arbor assy? I have measured the old spring (401616) (the slipping attachment has broken off) and dimensions are as follows (all mm, height 1.01, thickness 0.10, length 43.5 (could be +- 1.0), barrel diam 10.95 (say 11.0), barrel inside depth to top 1.24, cap thickness 0.23 and therefore spring space height calculated at 1.01 (similar to spring height). The slipping attachment has height 1.00, thickness 0.20 (thicker than mainspring) and 30 long joined to spring approx 6.5 from end of spring and slipping attachment. Any help/ideas will be much appreciated so I can fininsh my Pogue project.

 

[ClockBloke]

Give Stefan a try as he's been very good to me with hard to find bits n bobs.

 

[TheWatchBloke]

For the sake of £12 I'd just buy the 401615 from Stefan and try it. If it's a different part number it will be different in some way but the only difference that would really matter being they're from the same base calibre (61xx) is the arbor diameter.

 

[Daver]

Thanks for your replies. Re the arbor diam, the Seiko part no is the same for 6106A and 6139B so unless they use a generic numbering system then I assume they are the same physically. How do I contact Stefan (I am new to these forums!).

 

[ClockBloke]

Give seikochrono a pm

 

[Daver]

Found Stefan and have ordered 401615. Cross checked photo of my spring in its barrel before removing and photo on Stefans site, counted the coils etc and they look the same, so hope it fits! Will check basic dimensions before using and if way out will keep as stock or sell-on.

 

[TheWatchBloke]

Let us know how you get on, it's always useful to know what fits and what doesn't!

 

[Daver]

From Daver - Got new 401615 spring from Stefan and measured all I could without removing from holder. All dimensions appear to be same as 401616 but no details if different material (ie stronger/weaker which may effect power reserve and/or functionality). As the barrel was not 100% I decided to buy a new barre/arbor assy (205613) from Stefan, which again measures same as old one as expected as same part number. Have now fitted mainspring to barrel with some Moebius 8217 grease to the barrel wall. The arbor fits tightly into the spring and takes winding tension and the cap fit perfectly. The barrel/mainspring assembly fits well into the mainplate. Rebuilt chrono etc and all spins and works ok, but have had to stop assembly for now. Next step is to assemble pallet, balance and dial side. Watch this space!!

 

[ricardopalamino]

This is better than a Korean Soap....standing by , waiting for pics....

 

[Daver]

End of soap. No further feedpack or picks for this thread !!

 

[Daver]

Thought a final update may be useful for those interested.
Mainspring 401615 (works well, hand wound 6 full turns of barrel (maybe a bit more available but tight when stopped) and managed 42 hours running on bench before stopping, so good power reserve.
Had to replace intermediate date wheel 817610 (managed to damage this tiny plastic wheel when jammed on assembly!!), new one is actually metal so more robust (yet same Seiko part no.??).
Was running a tad slow on the timer so regulated faster, now run for 7 days without losing or gaining any time (timer indicated 0 to + 5secs/day), so all good.
Chrono works fine and keeps accurate time.
Decided to replace crystal (used a Sternkreus XMD 330.821 replacement) as original was very badly scratched, bezel fitted with no problems.
Dial has a few blemishes and flourescence has gone on hands etc but still looks fair, probably leave as is, as not capable of working on dial.
Case and bracelet refinished and polished.
Some pics attached.
Now to enjoy it!

 

[ClockBloke]

Lovely job and thanks for sharing your results!

 

[pollyc]

That looks like it has turned out well, I am impressed with how well these 6139 calibres run, your accuracy is impressive.

 

[Grammarofdesign]

Daver welcome to SCWF ! Your new 'Pogue' 6139- will stir a lot of hearts around here.

Great job on the full resto, you know your way around a watchmaker's bench much better than myself.

 

[Daver]

Thanks everyone for your advice and encouragment with my first complicated watch project. What a learning curve!! Still running well.
Now for my next project, to service my vintage (1966) Omega Seamaster Automatic. Should be easy after the Pogue !!

 

[Daver]

As I started this post enquiring about the mainspring, I thought an update apt.
The 401615 mainspring from the base movement (6106A/B) is performimg well.
I have worn for 11 days now, with the nightime on my bench dial up for about 9 hrs average before wearing again.
As there is no second hand I can only go by the dial markings (even used a loupe!) and have yet to see any loss/gain other than + or - 5 secs estimated, and this may only be my eyesight!
So I would conclude that the 401615 mainspring can successfully replace the unavailable 401616 mainspring.
Also Moebius 8217 in the barrel seems to work fine.
I used Moebius 9010 to replace Synt-A and Moebius HP1300 to replace Seiko S-4 and all seems fine.

 

[GuyJ]

Holy thread bump.

Compatibility of 6 series calibre complete barrel with arbor when it comes to the 6139B.

205.613

Compatibility of mainspring with 6 series calibre.
401.615/616

Will measure 6139B mainspring and update this thread so I have it...