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First attempt at servicing a movement


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Good day everyone

So, after practicing reassembly on a non working Seiko 7S26A with a dial foot lodged in the centre wheel, including rewinding (and breaking) a kinked mainspring, losing diafix cap jewels, and reinstalling a balance complete, I obtained two working movements from speedtimerkollektion., both 7S26A.

The first was advertised as "the movement runs and stops." Turns out the hands were bent downwards and the second hand was blocked by a dial index. Once that was popped off, the balance wheel swung back into life. I put it on my newly acquired timegrapher:

357F453C-7FFE-4045-9B1D-00A25C324F4C_1_201_a.thumb.jpeg.9db8145eb53dbdf572c5c28f12bda3f8.jpeg8D778D0A-1D0F-4565-8DA3-CAE58F539CF7_1_201_a.thumb.jpeg.6a758c61bdd45ac718b1f080f80cf361.jpeg

Found the readings varied somewhat depending on gain setting.  Compared it with the app WatchTuner so decided to settle on this reading. 4962C926-4A7D-45A5-9A46-68B003D24A76_1_201_a.thumb.jpeg.818a5536d033e912232709f7c6108e55.jpeg 

Decided to attempt my first ever service.  The parts were in worse shape than the previous non working 7S26 with crud and rusted areas.

Cleaned the parts with rodico, pegwood, and pithwood before ultrasonic cleaning in jars with Petroleum Ether, Propanol, and 2nd rinse Propanol (3 min each). Cleaned the pallet fork and balance by soaking in a jar of Hexane. My little 1L 55W cleaner struggles to remove all the gunk and rust. Placed a few parts in white vinegar for a few hours to remove the worst of the rust. Definitely have to work on my cleaning technique given what I'm seeing under the microscope. Some screws are still discoloured.

Reassembled and oiled using 9010, 9104, 9415 and 9504. Used S-4 on the first reduction wheel and pawl lever. Used notched pegwood to reinstall the diafix springs and a balance taper pin to oil the assembled diafix setting from the other side. My Chinese automatic oiler arrived with a bent needle that promptly broke so I am awaiting a new needle. 

I left the mainspring barrel well alone since it was winding and unwinding normally (unlike the previous practice movement).BDD30E14-C84D-4848-84D4-9C15F18AAD95_1_201_a.thumb.jpeg.9645b057e536a27ae2f15f64337731b0.jpeg

So this is the result without any regulation (which I have yet to delve into).

I've got the second working 7S26A to practice on then a complete Seiko 5 7S26A watch I picked up on Yahoo Japan auctions. Will work on these before any of my own 7S26 or 6R15 watches.    

So after the Chinese ST36 (6497 clone) (a true victim) and two 7S26As, I wanted to try my hand at hairspring manipulation, balance staff replacement, jewel adjustment etc. Turns out Seiko Ladies tiny form movements are not popular with collectors.  I obtained two working 1104A watches on Yahoo Japan Auction (for just 639 yen each) and nine non working 1104A movements from speedtimerkollektion (for about 1.50 to 2.50 USD each). Got some NOS spare parts so have some good practice material to work with. This is the first one I've started to disassemble. About the size of an American dime and older than I am.  

B264F880-28C4-4B1B-A6B6-B980BD831171_1_201_a.thumb.jpeg.7e5a0ca4605ee0e6549e63df0e461430.jpeg 

 

 

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Good job @JohnFrum👍

Does the 7s26 have those tiny cap jewels for the escape wheel and 3rd wheel? I did a 7s36B a year or two ago and found those tiny cap jewels so troublesome to handle that it completely killed my interest in Seiko movements. A shame really as those movements seem really good, and I'm just in awe of the "magic levers" for the automatic winding.

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12 hours ago, VWatchie said:

Good job @JohnFrum👍

Does the 7s26 have those tiny cap jewels for the escape wheel and 3rd wheel? 

Thanks. Yes it has the diafix cap jewels (apparently for oil retention) on the train-balance bridge for the escape and third wheel. The newer version though - the springs are the rectangular type. The smaller of the two springs in the photo. 
48CF7926-65A7-4C7F-9EB6-19C0906D0350.thumb.jpeg.5d3f1fad9cae043bac377268f75e12fe.jpeg 
The 21 jewel version of the 1104a uses the older U shaped diafix and the 3 lobed diashock springsEC0B5B9D-95ED-4952-861D-7840256A1629.thumb.jpeg.585fe71da1f3c939c943c8dc420290c1.jpeg

I followed Alex Hamilton’s instructions on making a notched pegwood tool to close these springs. That with a broken oiler finally ended the frustration at handling these diafix settings. 

Using the AliExpress Balance Tool (see Paul80’s excellent Chinese tool thread) I have disassembled the balance of an 1104a. Going to attempt restaffing. 
272C4231-ADA4-4C91-94A1-52115C84861C.thumb.jpeg.579449e661ee2a590a31427f41f1cb29.jpeg

Edited by JohnFrum
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10 hours ago, JohnFrum said:

Yes it has the diafix cap jewels (apparently for oil retention) on the train-balance bridge for the escape and third wheel. The newer version though - the springs are the rectangular type.

As I remember it, my 7s36B had the rectangular type and those dust-sized springs really made me sweat. I eventually got them into place but I also deformed one of them in the process. Before the Seiko, I had overhauled an Orient calibre 46E40 which is very similar to the Seiko 7s36B but using the diafix springs instead. As I remember it the diafix springs were fiddly too but not as fiddly as the rectangular Seiko springs. (My service walkthrough of the Orient 46E40 here).

10 hours ago, JohnFrum said:

I followed Alex Hamilton’s instructions on making a notched pegwood tool to close these springs. That with a broken oiler finally ended the frustration at handling these diafix settings. 

I would really like to see that! Can you provide some photos or a link?

 

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17 minutes ago, VWatchie said:

As I remember it, my 7s36B had the rectangular type and those dust-sized springs really made me sweat. I eventually got them into place but I also deformed one of them in the process. Before the Seiko, I had overhauled an Orient calibre 46E40 which is very similar to the Seiko 7s36B but using the diafix springs instead. As I remember it the diafix springs were fiddly too but not as fiddly as the rectangular Seiko springs. (My service walkthrough of the Orient 46E40 here).

I would really like to see that! Can you provide some photos or a link?

 


At 20 minutes in he makes a pegwood tool for the rectangular diashock/diafix springs. Makes the process a lot less fiddly. Still a PITA but much less chance of something pinging off and no five/ten/fifteen minutes of multiple attempts to get the spring tab into the slot. The flexibility and softness of the pegwood really helps here. 
In the video after this one, he demonstrates his method of working on the older style diafix. 

Edited by JohnFrum
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Thanks for the links! The springs for the balance are generally not that troublesome because they are quite a bit larger than the springs for the escape wheel and the 3rd wheel. I made a similar tool as Alex, for the escape wheel and 3rd wheel, but the problem is that the peg wood disintegrates when the size of the peg wood becomes this minuscule.

There are two types of peg wood from Bergeon, beech and hornbeam, and as I understand it, beech is a slightly harder wood than hornbeam. It could be that I only have hornbeam and really need beech. I'll have to look into it.

I'm still waiting for someone to demonstrate how to handle those super tiny springs in a safe and easy way, but I fear that the only way is by using two fine tweezers and a lot of practice as Mark is doing in this video at 13:25.

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1 hour ago, VWatchie said:

 

There are two types of peg wood from Bergeon, beech and hornbeam, and as I understand it, beech is a slightly harder wood than hornbeam. It could be that I only have hornbeam and really need beech. I'll have to look into it. ….

but I fear that the only way is by using two fine tweezers and a lot of practice as Mark is doing in this video at 13:25.

The beech is noticeably harder than the hornbeam and is available in a 2.0 diameter size. I used a piece of the beech for the diafix tool.

I’ve done the diafix in my scrap practice bridges with just two #5 tweezers. Works just some of the time. Need more practice but the frustration and cursing that accompany diafix and tweezers (and lost jewels and springs) is a deterrent. 

The notched pegwood is just so much easier IMHO. Takes most of the sweating and frustration away. 

Edited by JohnFrum
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3 hours ago, VWatchie said:

Thanks for the links! The springs for the balance are generally not that troublesome because they are quite a bit larger than the springs for the escape wheel and the 3rd wheel. I made a similar tool as Alex, for the escape wheel and 3rd wheel, but the problem is that the peg wood disintegrates when the size of the peg wood becomes this minuscule.

There are two types of peg wood from Bergeon, beech and hornbeam, and as I understand it, beech is a slightly harder wood than hornbeam. It could be that I only have hornbeam and really need beech. I'll have to look into it.

I'm still waiting for someone to demonstrate how to handle those super tiny springs in a safe and easy way, but I fear that the only way is by using two fine tweezers and a lot of practice as Mark is doing in this video at 13:25.

Tried it on a tool pick watchie, it worked well and got me out of a fix. Isnt orangewood used for pegwood as well ?

4 hours ago, VWatchie said:

Thanks for the links! The springs for the balance are generally not that troublesome because they are quite a bit larger than the springs for the escape wheel and the 3rd wheel. I made a similar tool as Alex, for the escape wheel and 3rd wheel, but the problem is that the peg wood disintegrates when the size of the peg wood becomes this minuscule.

There are two types of peg wood from Bergeon, beech and hornbeam, and as I understand it, beech is a slightly harder wood than hornbeam. It could be that I only have hornbeam and really need beech. I'll have to look into it.

I'm still waiting for someone to demonstrate how to handle those super tiny springs in a safe and easy way, but I fear that the only way is by using two fine tweezers and a lot of practice as Mark is doing in this video at 13:25.

A lot of practise and very steady hands. Holly is a lovely hard white timber that is easy to come by. Easily shaped when dried out and doesnt splitter like beach can. Used it for woodturning years ago. With a small lathe it could be turned to a useable size.

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