Seeking advice on installing watch crystal.

[Ruehara]

Repaired an old Tissot stylist a while ago, but the only thing I was never happy about was the crystal, polished it however there were some scratches that were too deep to remove. Recently found a matching acrylic crystal from cousins that should fit the watch. The problem is i'm not actually sure how to install the crystal into the case. It doesn't appear to be glued in, and there is a small lip in the crystal and a groove in the case for it to fit into. I tried using a crystal lift and also a crystal press (with round dies) on the old crystal as i don't mind damaging it. 

Any advice would be appreciated, hoping i'm missing something simple. Thanks!

[AndyGSi]

The only way I've ever know to do these is by hand.

[Neverenoughwatches]

1 hour ago, AndyGSi said:

The only way I've ever know to do these is by hand.

that's how I've always done them. Start at one side and work your way around feeding the edge in with your fingernails. If you hit a spot that won't enter, check that the edge isn't getting damaged, if so remove and feed that bit in first. if it's really tight you may need to reduce the size very slightly.

[Ruehara]

1 hour ago, Neverenoughwatches said:

that's how I've always done them. Start at one side and work your way around feeding the edge in with your fingernails. If you hit a spot that won't enter, check that the edge isn't getting damaged, if so remove and feed that bit in first. if it's really tight you may need to reduce the size very slightly.

Sounds like this might be the way then.

[AndyGSi]

I start with one long edge, then the 2 short ones, leaving the other long one till last.

[Ruehara]

Update: Tried installing the crystal by hand, and there is no way i'm getting that thing in, was applying quite a lot of force and the crystal just will not give. Is there a specific tool or an intended way of actually installing these type of crystal?

[caseback]

In watchmaking, there is supposed to be a tool for everything.. 

I believe there are dies that "flex" square crystals to reduce the outside dimensions. Robur-style, but square instead of round.

But, like @Neverenoughwatches already suggested, you could also make the crystal a bit smaller.

Edited 13 hours ago by caseback

[AndyGSi]

How does the size of the new compare to the old.

[Neverenoughwatches]

9 hours ago, Ruehara said:

Sounds like this might be the way then.

There are specific dies that will mostly fit this crystal shape, but I just find it easier doing them by hand. Occasionally the odd one can be difficult, there is a workaround, and it isn't by force .

8 hours ago, AndyGSi said:

I start with one long edge, then the 2 short ones, leaving the other long one till last.

Same Andy, generally it's possible to get 2 1/2  sides in before a little pushing is required. Things usually tighten up when the crystal is skewed too much, typically on smaller ones, I tend to try keeping them as flat as possible to the case lip

7 hours ago, Ruehara said:

Update: Tried installing the crystal by hand, and there is no way i'm getting that thing in, was applying quite a lot of force and the crystal just will not give. Is there a specific tool or an intended way of actually installing these type of crystal?

Have a measure up to see how well it does actually fit. Often the old ones were designed to be trimmed to size ( maybe not this one as it looks like a square version of a high dome, but still may trim down a little ) Manufacturers probably thinking it's easy to take off, impossible to put anything on.

4 hours ago, caseback said:

believe there are dies that "flex" square crystals to reduce the outside dimensions. Robur-style, but square instead of round.

I think would need something central of the crystal inside, while pushing the corners outside. 

Edited 9 hours ago by Neverenoughwatches

[Ruehara]

5 hours ago, Neverenoughwatches said:

There are specific dies that will mostly fit this crystal shape, but I just find it easier doing them by hand. Occasionally the odd one can be difficult, there is a workaround, and it isn't by force .

Same Andy, generally it's possible to get 2 1/2  sides in before a little pushing is required. Things usually tighten up when the crystal is skewed too much, typically on smaller ones, I tend to try keeping them as flat as possible to the case lip

Have a measure up to see how well it does actually fit. Often the old ones were designed to be trimmed to size ( maybe not this one as it looks like a square version of a high dome, but still may trim down a little ) Manufacturers probably thinking it's easy to take off, impossible to put anything on.

I think would need something central of the crystal inside, while pushing the corners outside. 

The crystal seems to be exactly the same as the old one, bought from Cousins using the model number of the watch. I tried again to manipulate it into the case but still having no luck. I think I will have to reduce the size slightly but am worried that once it's in, it could be loose. Before I do that I think I will try and design a custom shaped die for my crystal press and 3D print it. 

[AndyGSi]

What's the model number and what part have you bought.

[Ruehara]

The watch is a Tissot Stylist ref. 41429. I have managed to install the crystal now, I had to remove quite a bit of material from the edge until I could bend it into the case. Not ideal but atleast it's in. And it doesn't feel loose in the case which is what I was worried about. 

[RichardHarris123]

No photos? 

[Neverenoughwatches]

3 hours ago, Ruehara said:

The crystal seems to be exactly the same as the old on

When you say exactly,  how exactly ?  0.1mm can make a difference. I've trimmed fancy crystals to fit, the final fit is down to very small adjustments. The four corners maybe make the crystal more rigid than a round one.  

[Ruehara]

10 minutes ago, RichardHarris123 said:

No photos? 

Sorry, had to leave for work, will post photo when I finish. 

[AndyGSi]

So how did the dimensions stated as 30.1 x 25.3 compare with what you received and how do those figures compare with the original.