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Crystal Removal Problem


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Upon removing an acrylic crystal from a Seiko case, the crystal cracked at the base leaving the rest of it stuck in the case. It appears that whoever worked on the watch previously had glued the crystal in place as I’m unable to pry the rest of it out but only chip away at it. There is a lip on the inside diameter which makes it difficult to get a knife underneath the crystal. Any suggestions on how to best to remove the crystal?

crystal_2.JPG

crystal_3.JPG

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Hi   I would suggest warming it up to soften the glue and when its all out clean up with alchohol.  When I say heat it up , not with a blow torch , place some steel plate or such on the gas and warm it up  place  the case on the plate untill warmed  , wearing gloves remove the remains carefully .  use some dental picks if you can or somthing of that ilk.

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This case looks familiar... with some Seiko's of this era the crystal is kind of like a tension ring crystal with the tension ring removed, and the space in which the tension ring would fit in the crystal, fits onto a lip on the case. The bezel is then a tight fit around the crystal, which creates a better seal. Hope this description makes sense...

But if it is of this type, popping off the bezel may make cleaning up this mess a whole lot easier.

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7 hours ago, Lawren5 said:

The case appears to be machined from a single block with no removable bezel. I'll give the heating method a try.

Looking at the second picture in detail suggests that that case does indeed have a removable bezel... What is the exact model number of the watch?  From that we can determine the Seiko part number for the crystal. Some Seiko's of this period have a replacement crystal that comes cemented into a new bezel, quite often hard to get hold of at a reasonable price, if at all. I have got round this in the past by utilising the old bezel and fitting a generic crystal, fixing with UV setting glass adhesive...

Edited by JohnD
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22 hours ago, watchweasol said:

Hi   I would suggest warming it up to soften the glue and when its all out clean up with alchohol.  When I say heat it up , not with a blow torch , place some steel plate or such on the gas and warm it up  place  the case on the plate untill warmed  , wearing gloves remove the remains carefully .  use some dental picks if you can or somthing of that ilk.

      200 + degrees.    they make a melt pencil just for this AND just in case epoxy was used.  vin

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7 hours ago, JohnD said:

Looking at the second picture in detail suggests that that case does indeed have a removable bezel... What is the exact model number of the watch?  From that we can determine the Seiko part number for the crystal. Some Seiko's of this period have a replacement crystal that comes cemented into a new bezel, quite often hard to get hold of at a reasonable price, if at all. I have got round this in the past by utilising the old bezel and fitting a generic crystal, fixing with UV setting glass adhesive...

let us know how you make out.   vin

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OK, as it turns out the watch did have a removable bezel. Upon examination, it appeared not to have a bezel as there was no visible gap where a knife could be inserted and the fit was so precise that the case all looked like one piece. However, with a lot of pressure with a knife I was able to work around it and pry it off. Once off, the crystal was easily removed.

Thanks to everyone for all of your comments.

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17 hours ago, Lawren5 said:

The watch is model #7625-7003.

Sadly one of the 7625 watch models that Boley doesn't quote a crystal for...:(

 

Boley 7625.jpg

What is the diameter?

Edited by JohnD
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4 hours ago, Lawren5 said:

OK, as it turns out the watch did have a removable bezel. Upon examination, it appeared not to have a bezel as there was no visible gap where a knife could be inserted and the fit was so precise that the case all looked like one piece. However, with a lot of pressure with a knife I was able to work around it and pry it off. Once off, the crystal was easily removed.

Thanks to everyone for all of your comments.

good to hear, that what this forum is about...:thumbsu:

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