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Posted

I was able to remove the crystal from my Omega Cosmic single-piece case using the recommended air injection method with a hypodermic syringe that Mark demonstrated on his video. It took quite a bit of pressure but it eventually popped off. I'm ready to reinstall the crystal but the crystal press I have is of the inexpensive variety in which the dies are either flat or, if they concave the walls are straight, not tapered. Will I ruin this crystal if I use one of the straight walled dies to press it in? My fear is that the pressure will be concentrated on the middle 4/5 of the crystal and not spread to its edges where the crystal is strongest. Any tips on how to do this with this inexpensive press will be appreciated - I'd hate to invest in an expensive press at this time.

Thanks!

 

 

Crystal press 2.jpg

Crystal press 1.jpg

Posted

I have heard from members on here that these cheap crystal press tools do not line up well. So just be careful as the pressure needs to be even all around. I don’t think it will make much difference which type you use, a concave which has the walls of the die if it’s a good fit should keep it even. It shouldn’t need much pressure providing it is the correct glass. Just be careful.

Posted
2 minutes ago, manodeoro said:

For a tension ring crystal you'd better use such a tool.
https://uploads.tapatalk-cdn.com/20200917/4217f9391c92f1a7276df0df33b58a55.jpg
 

That should not be used for tension ring glasses. That tool is extremely good for high dome but it squeezes the glass and with a tension ring inside it cannot work correctly, it can mark the glass and distort the tension ring.   

  • Like 1
Posted

The cheap die will mark the center of the crystal. The brass insert slides out of the die and makes a circular scratch right in the center of the crystal. 

Ask me how I know...

I’ve not dealt with a tension ring crystal so I don’t have further advice. 

  • Like 1
Posted
5 minutes ago, Tudor said:

The cheap die will mark the center of the crystal. The brass insert slides out of the die and makes a circular scratch right in the center of the crystal. 

Ask me how I know...

I’ve not dealt with a tension ring crystal so I don’t have further advice. 

Agree.

Posted

I’ve fitted an original crystal on that same case reference (Cosmic). I used a cheap press. You need to make sure you use a cup which provides pressure around the perimeter of the crystal. 

  • Like 1
Posted

to insert a tension or armored ring crystal into the case you need a tapered die. Press on the outer edge only. Then if you're worried about scratching the crystal a thin sheet of plastic like a Ziploc bag works.

Posted

Thanks everyone for the advice. I will order a press that has tapered dies for sure, and I think I just found one from a reputable company that's not too expensive (cheaper than a new Omega replacement crystal for sure). 

Posted
49 minutes ago, DanB said:

Thanks everyone for the advice. I will order a press that has tapered dies for sure, and I think I just found one from a reputable company that's not too expensive (cheaper than a new Omega replacement crystal for sure). 

If you care to post the link we could advise you. Don't want you parting with you cash on something that might not be right. 

Posted

It's from Esslinger:

https://www.esslinger.com/deluxe-watch-tool-crystal-press-and-case-back-press-with-24-nylon-dies/

It has a big selection of dies and should include a tapered one that will fit the Omega crystal. I've read these less expensive presses do not apply even pressure due to the two dies not being perfectly parallel (as Old Hippy also noted). I thinking I'll manage this by applying only moderate pressure initially, rotate the watch a bit, apply pressure again, do this repeatedly, rather than just go in all guns and try to install it in one shot. It was good to read that Rodabod had success with a cheap press and the same reference

I have seen that Horotec offers a press that's not as expensive as a Bergeon, but with dies and such it will still run between $150 and $200. 

Any other product suggestions or comments on how I'm thinking of using the press?

Thanks

Posted

Hi all, 

I'm glad to report that the press from Esslinger did the trick. I had several tapered dies to choose from and the 34mm die fit nicely easing the crystal right into place. Having pressure only on the perimeter of the crystal avoided any trauma. Though my experience with this press is literally less than 24 hours old, I'd say it looks pretty robust. The dies fit nicely and they sit parallel to one another when on the press. For $60 it was well worth it. 

Press photo.jpg

Press on crystal.jpg

Press profile.jpg

  • Like 1
Posted

Great news!

You may want to invest in a package of “fender washers” to distribute the pressure over a greater surface. I have a similar press which ruined a GS crystal on me. The brass center came out of the plastic and marked it. 
 

Fender washers have a normal ID but are much larger on the OD than a typical washer. Make sure the ID is smaller than the OD of the brass. 

Posted

That's an excellent suggestion. While the brass center is currently recessed enough (just), better to be safe than sorry. 

Thanks!

Posted (edited)

Yeah, mine was fine; until it wasn’t...

Fortunately Rolex/Tudor do not require a (crystal) press and I made the bezel (which does require a press) die from aluminum. Actually the 16610 one I recently made us aluminum. The 1680/5512/9411 one is PVC I think... haven’t used it for a while. But I use my old fret setting press and not the crystal press. I should fix it up and get it going. 

Edited by Tudor
Posted

Wow, a fret setting press. Then you must be (or have been) a guitar builder, yes? That requires a high level of woodworking skills, working with such small tolerances.  

 

Posted

I use the drill press out in my shed,plastic bag  to prevent  scratches,using a socket  that about but does not reach the crystal  perimeter I press down. Of course I dont work on anything expensive. I have yet to break  anything. 

 

 

 

Posted

I also have used deep 12-point sockets of appropriate diameter in the past; but, I found that they may not press the retainer on flat/square and that’s a big deal with old friction rotating bezels. They can bind, have “hard” spots, be really loose or combinations. Making the die was much better. 
 

And I have also used the drill press in the past. 



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