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Discussion Starter · #1 ·
I have an SKX013 and a sapphire crystal I picked up for it, and whenever I try to press the crystal I just end up crushing one side of the gasket. I've gone through 3 now, and they're not cheap.

I'm following this video:
https://youtu.be/T0Zqit4r0wM

Using the same technique and equipment.

I'm using this crystal:
https://www.ebay.com/vod/FetchOrderDetails?itemId=273870254014&transactionId=2192257612017

I don't think the crystal is the wrong size because it seems to match up with the old one the watch came with.

Any suggestions? Photo attached.


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Measure both crystals they must be within .01mm, most gaskets go only one way as well a slightly thinner lip to the outside.
 

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Discussion Starter · #3 ·
Measure both crystals they must be within .01mm, most gaskets go only one way as well a slightly thinner lip to the outside.
Thanks!

Just measured the crystal with a digital caliper. It's exactly the same as the original.

How would I look up whether the gasket is one-way? I can't see any kind of taper or lip under magnification but I'm not positive.

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It happened to me once. They -measured- exactly the same, but the new one would not go in correctly. To diagnose...

Reinstall the old crystal. If that crushs the gasket too, then it's probably the installation technique (or cheap press) where the crystal is not going straight down. If you can reinstall the old one correctly but still have difficulty installing the new one, then it's probably slightly too big, difference too small for the caliper to detect.
 

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Thanks!

Just measured the crystal with a digital caliper. It's exactly the same as the original.

How would I look up whether the gasket is one-way? I can't see any kind of taper or lip under magnification but I'm not positive.
If the crystal measures the same as the original with a decent set of calipers, it's not the crystal that's the problem. I skimmed through the video you posted above, and the person doing the demo doesn't change the crystal gasket. These hard plastic gaskets are one time use only, and once they have been compressed they never return to their original size (and have the same holding power), so should be replaced every time as you are doing. He does the installation easily with a very cheap press partly because he's not changing the gasket, so the crystal goes in much easier.

So a few photos from a crystal change to illustrate what I do....case and new gaskets:



The gasket is always placed into the case. Most times, but not always, there will be a leading chamfer on the gasket and on this one you can see it at the red arrow, so that has to be positioned to received the crystal as you see here:



I then move to the press, set the crystal on top of the case, and get everything lined up - where possible I use another die on the underside of the case that aligns the case directly under the upper die. I have enough range of dies that I can find a diameter that locates the case precisely under the upper die. This is as important as selecting the right upper die in my view:



I then gently start pressing the crystal in, and once I get it started I check to make sure it's going in evenly. I rotate the case on the lower die, press it a little, rotate, press, and repeat until it's fully seated:



Once it's fully seated, I retract the upper die and let the case sit there for approx. 20 minutes or so. During this time, the gasket will "push" the crystal back out slightly, so I then go back and do the final seating of the crystal. In this video you will hear the click of the crystal seating in the case in this final step:


Then you are done. Make sure to look on the inside of the case to ensure that there is no gap between the case and crystal, and that no crystal gasket has been pinched and is visible inside the case. In fact this is why I changed the gasket in the watch above, because when I was servicing the movement, I noticed this:



I wasn't planning on removing the crystal, but I wasn't going to let this go. Whoever installed the crystal when the watch was last serviced didn't do a very good job.

You will note that my press is a large, heavy rack press, and if you are using the same equipment that is in that video, you most certainly have a challenge ahead of you. It's critical that the press is made well enough that the upper die is absolutely parallel to the lower die, and that the frame of the press is rigid enough to keep it that way during the pressing. Some of the cheap presses might line up okay, but I'm sure there's variability in them, and that means every press won't be accurate. The cheap presses are also not very strong, so I'm sure they flex.

These small cheap presses are fine for acrylic crystals, and even some thinner mineral or sapphire crystals, but when you get into thick crystals for dive watches that use tall gaskets and heavy interference fits, they may not be well suited.

Anyway, hope this all helps.

Cheers, Al
 

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Test fit the gasket on the crystal first then measure the gasket while on it, it will be slightly smaller dia when correct as opposed to if backwards, if the same then it is a true flat side gasket and can be used both ways. Then measure the ID of the opening. The opening should be within a margin maybe .05mm smaller, I have seen where it can be up to .5mm but that's very tight in my opinion. If crystal is correct then gasket may be too thick. There are different styles of openings, flat side, tapered channeled and others that won't apply to your watch depending on the WR of the case and that will be evident when looking close at the opening. You should be able to start the crystal with your fingers slowly moving around to get the initial seat, then use the press a little and rotate a few times to get a flat seat.

Thanks!

Just measured the crystal with a digital caliper. It's exactly the same as the original.

How would I look up whether the gasket is one-way? I can't see any kind of taper or lip under magnification but I'm not positive.

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The chamfer is very difficult to see especially with the black gasket. I have a stereo microscope and even with that it is hard to see. I have to change the lighting and rotate it around to confirm.

I think that gasket is an L shaped gasket. It is on its big brother. Go slow and get it perfectly straight. Much easier to type that than do it.
 

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I'm a newbie and having my own problems right now, but the only way I could get my new gasket and crystal seated properly was my bench top vise and shims. This was recommended by someone else on here.
 

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With the gasket out, measure the openning. Order a crystal exact or no more than .02mm smaller, then glue it in. I use a vegetable oil pressure sprayer with distilled water to test case seal with movement out.
 

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I'm a newbie and having my own problems right now, but the only way I could get my new gasket and crystal seated properly was my bench top vise and shims. This was recommended by someone else on here.
That's interesting, so you put your press dyes and the watch sideways in the vise, then clamped it down?
Could be a really great idea to get more clamping pressure!
 

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That's interesting, so you put your press dyes and the watch sideways in the vise, then clamped it down?
Could be a really great idea to get more clamping pressure!
Exactly. A better press would probably be the best option, but the vise worked well for me. I was just very careful!
 

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Discussion Starter · #13 ·
The issue here was that the case was deformed. I've set a couple dozen in other watches now with no issue. I took this watch in question to a professional watchsmith and surprise he crushed the gasket too. The case was just slightly deformed.
 
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