ETA 2472 - how to tackle this crown and stem?

[Klassiker]

The spring keeps the threads of the crown and crown tube separated while you are winding the watch. It will work without, but the risk of the thread engaging, or worse, cross-threading, is high. The split stem needs to give the crown enough end float to disengage from the thread, but leave the main part of the stem and the keyless works in the winding position.

4 hours ago, Michalzeszen said:

And is there a possibility to convert it to a springless system by replacing it with a standard split stem model?

A standard split stem will probably not have the end-float you need. It has no advantages over a one-piece stem in this application, because when you unscrew the crown the stem will be drawn out and the keyless works will move from the winding position to the setting position.

The conventional reason for having a split stem is to enable removal of the movement when the stem release is not accessible, e.g. when you have an integrated case back. As has already been pointed out, you don't need this feature.

Hopefully your watchmaker pal will get the screw-down feature to work in harmony with the "special" split stem he has in stock. If not, ask him to remove the screw-down feature ( remove the thread from the crown and / or case) and fit a conventional stem.

Edited Thursday at 05:37 AM by Klassiker

[AndyGSi]

Not while maintaining the screw down crown as I mentioned above.

12 hours ago, AndyGSi said:

If they want to use the original screw down crown then yes it's necessary, otherwise there's no play from the winding position to screw it down

[Michalzeszen]

On 5/8/2025 at 3:09 AM, AndyGSi said:

Not while maintaining the screw down crown as I mentioned above.

Unfortunately, I couldn't source the correct part from the old folks. I did find this:
https://lobtime.com/shop/ols/products/screw-down-crown-kit-set-of-5-for-titus-calypsomatic-diver-watch-technos-skydiver-fayt

It is much more than I should pay for a set, but it is interesting to see that someone is producing it to keep up with a somewhat rare demand.

[Nucejoe]

 Can't you solder male and female parts of the stem together, it'll do as a one piece stem.

 

 

[AndyGSi]

41 minutes ago, Nucejoe said:

 Can't you solder male and female parts of the stem together, it'll do as a one piece stem.

So how would that give you the end play from the screw down crown?

5 hours ago, Michalzeszen said:

Unfortunately, I couldn't source the correct part from the old folks. I did find this:
https://lobtime.com/shop/ols/products/screw-down-crown-kit-set-of-5-for-titus-calypsomatic-diver-watch-technos-skydiver-fayt

It is much more than I should pay for a set, but it is interesting to see that someone is producing it to keep up with a somewhat rare demand.

That is a bit on the pricey side.

I wonder if it's possible to drill the second hole yourself in a normal split stem?

[Nucejoe]

27 minutes ago, AndyGSi said:

So how would that give you the end play from the screw down crown?

 

48 minutes ago, AndyGSi said:

So how would that give you the end play from the screw down crown?

 

Didn't think of that.

[Klassiker]

6 hours ago, Michalzeszen said:

It is much more than I should pay for a set, but it is interesting to see that someone is producing it to keep up with a somewhat rare demand

I don't know the details of their production set-up, but for small batch production 50 USD seems not unreasonable for the set. The photos are excellent. The parts appear to be very well made. It should be clear now how they all work together.

[AndyGSi]

It maybe worth a message to them to see if they'd just supply the part you need.

You'll also need to confirm the thread size to check it matches your crown.