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Seiko 7546


markr

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It is complicated.  Too complicated to describe.  Look for the "Seiko Casing Guide".  The case back will have a letter code that guides you to the correct procedure.  I think I know what model that is and I have one that I did.  Be warned, there are no new gaskets available for the bezel assembly and it is nylon so shouldn't be reused.  Generic crystal gaskets are similar but don't work well.  I ended up buying a nylon gasket set and tried at least 3 different sizes before I found one tight enough and it was nowhere near the size I measured.  Lastly, the only die size that works is in the Seiko S-220 tool kit.  Generic or plastic dies don't fit correctly. 

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Google this "seiko case servicing guide"  There is a link from seikoserviceusa that will get you to a good casing guide.  If your watch is the same as mine, it should be Case Code G

I could not find a die that fit correctly in my chinese made press.  The Seiko S-220 fits perfectly.  And on this one, the die has to fit perfectly.  The ring that holds the glass is very thin

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2 hours ago, bklake said:

Google this "seiko case servicing guide"  There is a link from seikoserviceusa that will get you to a good casing guide. 

No need to even leave this forum, the guide has been posted repeatedly and can be found using the search box top right. Here it is again.

1982.03 Seiko Case Servicing Guide.pdf

And the module service guide 

Seiko 7546A - Technical Guide.pdf

Quote

I could not find a die that fit correctly in my chinese made press.  The Seiko S-220 fits perfectly.  And on this one, the die has to fit perfectly.  The ring that holds the glass is very thin

it's common  to have to make one own own tools, in this case a die. Although  a lathe is required - a wonderful tool to have and learn about.

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The Case Servicing Guide is a different document.  It is not caliber specific, it is case code specific.  The case code can be found on the case back.  The 7546 was produced around the time that Seiko went to a new code system and it is confusing which code is the code to use.  My 7546 that looks similar to his has a code placement similar to the new system and old system except One code is in a circle rather than a box.  That case code leads you to a square case style that doesn't look anything like the watch.  The case code following the "old" system is the correct one.  Thankfully, the guide is full of pictures/diagrams because I need that.  I couldn't put the link address because it goes straight to a .pdf download for me. 

At first, I suggested searching for "Seiko Casing Guide".  That will lead you to older documents up until the early '70s.  Seiko changed the name to "Case Servicing Guide" in the late '70s early '80s.  Both are useful to have saved. 

He will need the 7546 movement guide in the near future.  This caliber responds extremely well to a clean and service.  And it is very easy to do.

I agree about a lathe and I have one.  I took a shortcut when the Seiko S-220 die set came up.  It is shaped and sized perfectly for Seiko case and crystal work.   I'm not sure I could duplicate the dies on my lathe.  Lack of skill mostly. 

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