seiko question

[yankeedog]

I have a 7s26 with a broken balance staff. I have a partial 7009 with a good one. the balance cocks do not interchange. Does anyone know if the balance /hairspring  can be transplanted from the 7009 to the 7s26 balance cock ?

[AndyHull]

1 hour ago, yankeedog said:

I have a 7s26 with a broken balance staff. I have a partial 7009 with a good one. the balance cocks do not interchange. Does anyone know if the balance /hairspring  can be transplanted from the 7009 to the 7s26 balance cock ?

Nope. I have no idea. In fact, I can only think of one way to find out.

Well two actually, but the second one requires carefully measuring and photographing them both, so I suspect I would just try it and see.

.. well three... I can only think of three ways to find out. If you can figure out the part numbers for each, and if they match.. but I guess that is stating the obvious.

 

OK Four ways... check with ranff.. the balance staffs look to be different.

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&Seiko_7009A

http://www.ranfft.de/cgi-bin/bidfun-db.cgi?10&ranfft&&2uswk&Seiko_7S26A

 

 

.. but that doesn't mean you cant try it and see.

Edited April 12, 2019 by AndyHull

[JohnR725]

 

 

0310020
 BALANCE COMPLETE
 721/1909

  BLF 12G1B2      21600 BPH-17JL-AUTO-CALD
 JUB 1201     
 JUB 1202     
 PUL Y621     
 QUA 12G1B2      21,600 BPH-17JL-AUTO-CALENDAR
 SEK 7001A      17 JL-21,600 BPH-DSS-AUTO
 SEK 7002A     
 SEK 7005A      21,600 BPH-17 JL-SHOCK-DSS-AUTO-CALENDAR
 SEK 7006A      21,600 BPH-17 & 21 JL (19 JL)-DSS-AUTO-CALD(DAY DATE)
 SEK 7009A      21,600 BPH-17 JL-SHOCK-DSS-AUTO-CAL. (DAY DATE)
 SEK 7015A      21600 BPH 21JL AUTO CHRONO CALD (DAY/DATE)
 SEK 7016A      17JL 21600BPH CHRONO AUTO CALD DAY DATE
 SEK 7017A      21JL 21600 BPH AUTO CHRONO CALENDAR (DAY/DATE) SHOCK ADJ STD
 SEK 7018A      21600 BPH 23JL AUTO CHRONO CAL (DAY/DATE) ADJ STUD HOLD
 SEK 7018B      23JL 21600 BPH CHRONO AUTO CALD (DAY/DATE)
 SEK 7019A      21,600 BPH 21 JL DSS AUTO CAL (DAY-DATE)
 SEK 7025A      21,600 BPH-SHOCK-17 JL-DSS-AUTO-CALD W/CORR-ADJ STUD H
 SEK 7S26A     
 SEK 7S36A      SEE TECH GUIDE FOR DESCRIPTIONS OF DAY DIALS
 UTC 37      21,600 BPH 17JL DSS AUTO CAL
 UTC 38      21600 BPH-DSS-AUTO-CALD (DAY/DATE)-SHOCK
 WCX A331-1      21,600 BPH-17 JL-SHOCK-DSS-AUTO-CALENDAR
 WCX A361-1      21,600 BPH-17-19-21 JL-DSS-AUTO-CALD-(DAY-DATE) SHOCK

[AndyHull]

Just now, JohnR725 said:

 

 

0310020
 BALANCE COMPLETE
 721/1909

  BLF 12G1B2      21600 BPH-17JL-AUTO-CALD
 JUB 1201     
 JUB 1202     
 PUL Y621     
 QUA 12G1B2      21,600 BPH-17JL-AUTO-CALENDAR
 SEK 7001A      17 JL-21,600 BPH-DSS-AUTO
 SEK 7002A     
 SEK 7005A      21,600 BPH-17 JL-SHOCK-DSS-AUTO-CALENDAR
 SEK 7006A      21,600 BPH-17 & 21 JL (19 JL)-DSS-AUTO-CALD(DAY DATE)
 SEK 7009A      21,600 BPH-17 JL-SHOCK-DSS-AUTO-CAL. (DAY DATE)
 SEK 7015A      21600 BPH 21JL AUTO CHRONO CALD (DAY/DATE)
 SEK 7016A      17JL 21600BPH CHRONO AUTO CALD DAY DATE
 SEK 7017A      21JL 21600 BPH AUTO CHRONO CALENDAR (DAY/DATE) SHOCK ADJ STD
 SEK 7018A      21600 BPH 23JL AUTO CHRONO CAL (DAY/DATE) ADJ STUD HOLD
 SEK 7018B      23JL 21600 BPH CHRONO AUTO CALD (DAY/DATE)
 SEK 7019A      21,600 BPH 21 JL DSS AUTO CAL (DAY-DATE)
 SEK 7025A      21,600 BPH-SHOCK-17 JL-DSS-AUTO-CALD W/CORR-ADJ STUD H
 SEK 7S26A     
 SEK 7S36A      SEE TECH GUIDE FOR DESCRIPTIONS OF DAY DIALS
 UTC 37      21,600 BPH 17JL DSS AUTO CAL
 UTC 38      21600 BPH-DSS-AUTO-CALD (DAY/DATE)-SHOCK
 WCX A331-1      21,600 BPH-17 JL-SHOCK-DSS-AUTO-CALENDAR
 WCX A361-1      21,600 BPH-17-19-21 JL-DSS-AUTO-CALD-(DAY-DATE) SHOCK

I presume that means that if you use a ...

0310020
 BALANCE COMPLETE
 721/1909

It should work with all of the movements listed?

[aac58]

Part # of Balance complete with stud for 7S26C is 0310197 and for 7009 is 310 020, so I'm afraid they are not compatible.

 

However the balance in 7S26A is 310 020, so it is the same than in 7009.

[JohnR725]

3 hours ago, aac58 said:

Part # of Balance complete with stud for 7S26C is 0310197 and for 7009 is 310 020, so I'm afraid they are not compatible.

 

However the balance in 7S26A is 310 020, so it is the same than in 7009. 

My reading skills totally suck I didn't notice the letter C and you're right that changes the answer totally. So the correct cross reference should look like this.

0310197
 BALANCE COMPLETE WITH STUD
 SEK 7S26C      21 JEWELS
 SEK 7S36C

 

 

[TexasDon]

With the C version, Seiko changed the balance staff and regulation system entirely. They aren't compatible with any other model to my knowledge except the B version which was replaced by the C version. 

[jdm]

As noted, the 7009 has the same balance as the 7S26A.
For 7S26 parts change across versions one can check my table:

https://docs.google.com/spreadsheets/d/e/2PACX-1vRN2UULQKTfKmhRStZhDdIOIQrqd6sPB-g6x2SKyQQjOvTBjG_7TQXQhAT4f1WqAX5QAPkIimi-3jqd/pubhtml 

[jdm]

16 hours ago, TexasDon said:

With the C version, Seiko changed the balance staff and regulation system entirely. They aren't compatible with any other model to my knowledge except the B version which was replaced by the C version. 

I don't think the balance staff was changed, but that's not relevant to practical repair because only the balance complete is orderable, and it not meant to be taken apart. What was changed on the balance complete is just the hairspring end stud. One can fit A/B/C types across versions as long the arm (in practice, the entire balance cock) is matching the end stud. These also fit Seiko 4R, 6R series and their SII equivalents, although the latter have different P/Ns and materials and finishing.

[Nucejoe]

 My understanding is the 7*** series are all of the same family, nevertheless, staffs are refernced differently. May fit but not exact same.

[jdm]

4 minutes ago, Nucejoe said:

 My understanding is the 7*** series are all of the same family, nevertheless, staffs are refernced differently. May fit but not exact same.

What I was saying above is that "staffs" are never referenced, only the balance complete is. And if you take apart one of these most likely it will not run properly if put back together.

[Nucejoe]

28 minutes ago, jdm said:

What I was saying above is that "staffs" are never referenced, only the balance complete is. And if you take apart one of these most likely it will not run properly if put back together.

Right, The HS on some of balance complete were not meant to be replacable, the collet breaks comes out in pieces.

[yankeedog]

I absolutely love you guys.... since I have nothing to lose and it does not appear to be a "C" version I will have to attempt  the swap. I will report back with the results.

[yankeedog]

thanks for all your input, but in this instance it was a case of negative luck.

[nightwatchman]

I have two 7S26As. One is working fine and the other lost a roller jewel a few years back and has sat dormant until I got off my bottom and got more in to watch repair. My question is, would it be possible to get the cheaper and more readily available 7S26B/C part and just replace the HS end stud so the  0310197 effectively becomes a 0310020? 

Another option is to get a replacement roller jewel - while they are £5 for an assortment of 100 on ebay, there is not guarantee that the pack will contain one that suits. 

Any advice from experience?

[jdm]

59 minutes ago, nightwatchman said:

I have two 7S26As. One is working fine and the other lost a roller jewel a few years back and has sat dormant until I got off my bottom and got more in to watch repair. My question is, would it be possible to get the cheaper and more readily available 7S26B/C part and just replace the HS end stud so the  0310197 effectively becomes a 0310020?

Not really. The end stud is glued and the spring very delicate, attempts to mess with it most likely ends badly.

Quote

Another option is to get a replacement roller jewel - while they are £5 for an assortment of 100 on ebay, there is not guarantee that the pack will contain one that suits. 

The balance assembly is sold as "complete" only for good reasons, its construction does not allow in practice to take apart staff, roller jewel, stud and without damage, and put them back with precision, as you can read reported above.

Quote

Any advice from experience?

 

That you use an A balance, or B/C one replacing the balance cock also. I have seen -but not tried- non-original balances on Ebay going for very little. If you want to try anyway for practice I can send you parts for free but with a bad hairspring.

Edited June 20, 2019 by jdm

[CaptCalvin]

On 4/13/2019 at 11:56 AM, Nucejoe said:

Right, The HS on some of balance complete were not meant to be replacable, the collet breaks comes out in pieces.

I have separated the HS from balance on these a few times. Side note these almost never come out of the box properly centered as you can see in the first pic out of a freshly bought movement.

Edited June 20, 2019 by CaptCalvin

[jdm]

18 minutes ago, CaptCalvin said:

Side note these almost never come out of the box properly centered as you can see in the first pic out of a freshly bought movement.

I find Seiko HS manipulation to be very difficult. When you have a chance, why not posting a video to show your technique to others. 

[CaptCalvin]

36 minutes ago, jdm said:

I find Seiko HS manipulation to be very difficult. When you have a chance, why not posting a video to show your technique to others. 

It would just be a video of me poking and prodding for hours I'm afraid. But the basic procedure for me is, move the index right next to the stud holder, and rotate stud so that the hairspring at this point is centered in the index. Then I move the index little by little away from the stud. If at any point as I'm advancing the index I see the hairspring start to deviate from the center of the pins I back the index up and either tighten or widen the curve, checking the curvature by moving the index over the problem spot after every manipulation. I keep doing this until I get to the dog leg and now I have a perfectly formed end curve. Next is to just fiddle with the two bends at the dog leg to get the collet to center on the jewel. Also check constantly that the collet isn't sticking to the cock by tapping on the cock whenever you are checking your work to make sure the hairspring is in its fully relaxed state.

I don't have any special techniques really. It's basically just time and patience. Feel free to ask though if you want me to be a little more specific about anything.

[saswatch88]

you can get a 7s26 for $25 complete and running on ebay

[nightwatchman]

On 6/20/2019 at 5:45 PM, jdm said:

Not really. The end stud is glued and the spring very delicate, attempts to mess with it most likely ends badly.

The balance assembly is sold as "complete" only for good reasons, its construction does not allow in practice to take apart staff, roller jewel, stud and without damage, and put them back with precision, as you can read reported above.

 

That you use an A balance, or B/C one replacing the balance cock also. I have seen -but not tried- non-original balances on Ebay going for very little. If you want to try anyway for practice I can send you parts for free but with a bad hairspring.

Thank you for some great perspectives there jdm. I would like to take you up on your offer of the practice parts. Really appreciate that. I will DM you. 

Regarding the replacement cheapie parts. I am working on an Orient F6922 which I messed the HS up on while moving the end stud. It made the HS want to run along the shortest distance between the end stud and regulator pins. I have ordered 2x new balance wheels with HSs for the grand sum of £3.96. Will report how these perform. They are advertised as 46943 parts, but I am going to investigate how much Orient changed when coming up with the F69.