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I'm reasonably new to the hobby. Really enjoying it. However I seem to have a continuous problem and it's annoying me no end.

Buying a watch to work on. Needs some parts, some are broken, parts missing, items been placed incorrectly. I can handle that, buy new parts etc. Here in lies the problem, these are old watches and the only way to get parts is by buy other old watches and use the parts as spares and replace when necessary.

Here's the annoying rub. Purchase the same movement (Seiko mainly) and the same movement is different in parts and movement. 

Photographs of the 7S26 base pates. The same but different. The parts on the movements look the same , but they are also different. 

So annoying.20220706_184800.thumb.jpg.d75d6430786370c1de2554bd5a3e4bdc.jpg

20220706_184811.jpg

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1 hour ago, rossjackson01 said:

Here's the annoying rub. Purchase the same movement (Seiko mainly) and the same movement is different in parts and movement. 

Photographs of the 7S26 base pates. The same but different. The parts on the movements look the same , but they are also different.

It's all about researching or asking, in this case even Seiko enthusiasts know that 7S26 has been made in three versions, A B and C, that also has been discussed many times here. Below a parts compatibility sheet shared by myself.

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

Note if you aim for a sure repair the best option is to buy a brand new complete NH36 movement. That will give you manual winding, seconds hacking, and plenty of spare parte from the old one, for little money on top.

Edited by jdm
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That's correct. Multiple iterations on the same movement, superseding each other without a much to make it obvious. It's been a while, but I had two version of the same 7s26 watch; one I bought in college, and the other was replaced by insurance when the first was destroyed in a car wreck. The first, I think, was an A or B, and the second was a C. For sentimental reasons I wanted to fix the original, and figured I'd use parts from the second to fix the problem. I ran into exactly what you did. I ultimately ended up using the case and hands, and got an aftermarket dial, domed sapphire crystal, and a new NH38 (I think that's the one without a date). Now it's my "shop watch" for when I'm working on things I don't want to subject my daily driver to. I recall the _/A/B/C iterations are noted on the rotor, or maybe on the main plate somewhere if you know to look. Maybe it's because of what I learned with the Seiko, but I've not run into that particular issue with any other movements for whatever that's worth.

Edited by spectre6000
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