Pressing in armored glass - Vostok

[shiz]

Good morning, i need some help refitting a domed acrylic crystal for a vostok amphibia. The exact model is the 420 case

I recently had an accident where a sprung handle spun violently and hit my watch. A true testament to how sturdy these watches are - the watch took most of the hit, which would have surely broken my wrist and continued working for a few weeks after.

In the process, there was some issues with the movement (resolved) but the crystal also cracked. So i set about to replace it. Sourced the part HERE. I believe this is called armored glass? (forgive me if im not using the right term - newbie)

The old glass used a sealing ring, which i intend to reuse. The new glass comes without the sealing ring but can be bought separately. I dont see the reason why i'd need a new one?

My questions:
1. I cannot seem to be able to get the (old) sealing ring to sit in the (new) glass. Most of the replacements i've seen come with the ring pre-installed. Is this going to be an issue? Do i need the sealing ring already installed or can i do it myself? If so, how?

2. What type of press do i need to for this? I've read aluminium dies with a chamferred edge, however i've seen others use nylon.

anything else im missing here.

Edited November 1, 2023 by shiz

[Malocchio]

You can use the old ring if the glasses are otherwise perfectly similar. If the new glass doesn't come with a tension ring, it probably isn't supposed to have one. All armoured glasses I've seen come with a ring.

[shiz]

The glass should be identical to the old one, i havent put the calipers to it to measure but when i overlay the old and new crystal they seem identical. Ill do a proper measurement.

As for the glass requiring the ring...they mention that directly on the website:

[Nucejoe]

5 hours ago, shiz said:

 when i overlay the old and new crystal they seem identical. 
 

This is likely to be more accurate than measuring with calipers.

Rgds

[shiz]

9 hours ago, Nucejoe said:

This is likely to be more accurate than measuring with calipers.

Rgds

My dry fingertips are accurate to 3 microns 

[mikepilk]

On 11/1/2023 at 5:33 PM, shiz said:

1. I cannot seem to be able to get the (old) sealing ring to sit in the (new) glass.

I think there's some confusion with the tension and sealing rings. Maybe a confusion in translation?

The glass shown in your link does have a tension ring, inside the acrylic. But it doesn't seal. 

The sealing ring is a thin plastic ring that goes around the outside. You sit it in the watch, then press the glass in.

 

[shiz]

18 minutes ago, mikepilk said:

I think there's some confusion with the tension and sealing rings. Maybe a confusion in translation?

The glass shown in your link does have a tension ring, inside the acrylic. But it doesn't seal. 

The sealing ring is a thin plastic ring that goes around the outside. You sit it in the watch, then press the glass in.

 

Thank you for the clarification and the reply. I think its probably a combination of the translation and me being new to this. Apologies for the confusion.

At any rate, the new glass just came wrapped in some bubble wrap. It did not come with a sealing or tension ring. 
So i guess my question still applies (now that we have the correct terminology) - is it a problem that the tension ring is not already attached to the new glass? Is it a part of the factory manufacturing process? Or can it be pressed to the glass, and then the glass+tension ring pressed to the case?