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Removing mineral glass without crystal press?


SudoHalt

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Hey there, 

I would like to work on just another disassembly, albeit patiently, but I seem to have the wrong cheap watch to start with. 

From the pictures, it could be seen that the case is milled to exactly the movement diameter. In other words, the movement holder is actually an integral part of the case.

This means I can't remove the movement and the dial as a single piece. Instead, I'll have to remove the mineral crystal first, which will likely make the movement and dial removable in one piece. And even if it is not the case, removing the hands safely is certainly better than attempting to remove the movement from the case back side anyway. 

The crystal is definitely mineral, even with an anti scratch coating. The edges are beveled and there's absolutely no way to grip it with the acrylic crystal remover. 

If it helps, the crystal is big, at least 37mm in diameter. 

What are my options? I have my nuclear option but I don't want to act stupid.

Bonus question : what's the movement? It sort of resembles the ST-16, except that it isn't (but I can be wrong) 

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Edited by SudoHalt
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If indeed the mvtholder is part of the case(of which I am not sure according to the photos) you can gently put a bench knife between the bezel and the case and take the bezel of, normally the crystal should be held in place by the bezel.

The crystal is a normal crystal, not a very big size.

 

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23 minutes ago, Watchtime said:

If indeed the mvtholder is part of the case(of which I am not sure according to the photos) you can gently put a bench knife between the bezel and the case and take the bezel of, normally the crystal should be held in place by the bezel.

The crystal is a normal crystal, not a very big size.

 

Thanks a lot. Probably the crystal isn't large, but it's the largest watch I ever laid my hands on!

May I ask, since I have never attempted this, how much force should be required? I have previously removed the rotating bezels on Seikos and Vostoks. Should I expect this one to be as easy, or is there considerably more force required?

On the other hand, I am preparing for the scenario where the bezel is too tight. Apart from breaking the crystal, I got another stupid idea... Since I am able to feel the crystal gasket by my nails, do you think it's a reasonable idea to attempt to rupture the crystal gasket by the means of a razor, in order to free the crystal?

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As said by watchtime I also agree with his comments and would think that the bezel removes with the crystal intact. Some require a fair degree of force to remove and may need a tool such as the tool attached.  Refrain from trying to work the crystal out as this may lead to damage of the bezel and the crystal seating and ruin the gasket.

s-l1600.jpg

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4 hours ago, SudoHalt said:

 Since I am able to feel the crystal gasket by my nails, do you think it's a reasonable idea to attempt to rupture the crystal gasket by the means of a razor, in order to free the crystal?

No I don't think is a reasonable idea. A caseback press that can also do some crystal work is very cheap. In watchmaking as well other trades the idea is that one tries hard to repair, not break things. 

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Depends on the wtch/brand. What brand is it? Can you post a photo of the front of the watch. It is supposed to keep water out so it should not be very loose...?

Take a razor blade or a sharp bench knife to get it off, you can put a piece of gaffer tape on the bezel/cae and cut through it. You wan;t get scratches then....I am wondering where you feel the gasket? Not on the front I guess? To be sure, have a replacement gasket ready, When replacing crystals with gaskets, I change these too.

Edited by Watchtime
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