Aftermarket exhibition caseback

Scarecrow Boat · Mar 27, 2023

N nickjust
Thanks, good to know. Should the inner o ring sit in a channel within the case back to keep it in a round shape? Or it's just loosely laid in there and you hope for the best when screwing the caseback down? The reason I ask is I noticed the attached photo from another forum member (@mutanthands) where the gasket doesn't appear to have made proper contact. However, it might just be my eyes and what I think I'm seeing in the photo (circled red) isn't actually the gasket.

It’s not so much a channel (like the actual Case o ring) but more like an area for the o ring to sit against.

These images belong to @140dave and can be found at his recent listing
https://omegaforums.net/threads/speedmaster-sapphire-exhibition-caseback-aftermarket.157807/

There is no grease on the o ring and it does sit flush against the movement. The o ring will last as long as you don’t repeatedly remove the case back.

nickjust · Mar 30, 2023

Thanks @Scarecrow Boat , that answers my question perfectly 😀

teamlam · Apr 4, 2023

anyone know if spiral watches open case back wil fit my speedy 3575.20?

Scarecrow Boat · Apr 15, 2023

Just sharing this one once more because I like it. Metal brake upgrade to further compliment the sapphire case back,

MattAu · Apr 30, 2023

Thank you to those who posted pics. I have now installed one on mine.

nickjust · May 1, 2023

MattAu
Thank you to those who posted pics. I have now installed one on mine.

Looks good. Pleased with the result?

MattAu · May 1, 2023

N nickjust
Looks good. Pleased with the result?

Yes, I haven't detected any negatives so far. The watch wears thinner, as others have pointed out, and I like the fact that most of the engraving is there except for "by NASA"

G4_Chrono · Jul 6, 2023

Scarecrow Boat
I got an update that spiralwinder casebacks are now in stock and noticed they have an engraved option. I’d love to get an OEM exhibition back, but as those are quite pricey and harder to find, I was happy to try out spiral’s option. It just arrived and it’s quite nice. No idea how well the enamel will hold up, but for the price and quality, this definitely scratches the OEM itch. 👍

Love seeing that movement! I am hovering over the checkout button to fit on my 1861 😀

Apologies if the answers are already in the thread, but have you switched the Delrin brake on yours?

Also, I am hoping with this new spiralwinder case back it will be thinner and thus sit on (into?) the wrist in a similar way to the 3861 Speedmaster. Are you able to confirm that?

Thanks!

Scarecrow Boat · Jul 6, 2023

G4_Chrono
Love seeing that movement! I am hovering over the checkout button to fit on my 1861 😀

Apologies if the answers are already in the thread, but have you switched the Delrin brake on yours?

Also, I am hoping with this new spiralwinder case back it will be thinner and thus sit on (into?) the wrist in a similar way to the 3861 Speedmaster. Are you able to confirm that?

Thanks!

Hey, yes I have modified the movement so that I have the metal brake. No benefit other than for looks 😀

And yes, I can confirm that this caseback is very thin and wears as such.

watch_my_six · Aug 18, 2023

L Lewj
Update on the Spiral Winder caseback situation for my CK 2998 Pulsometer bezel.

I looked like there is no suitable caseback for my watch, available through Spiral Winder. Warren has reached out to me and issued a full refund.

Since I am in Canada, shipping the item back would have been too costly, and he has relinquished the item for me to keep.

If anyone located in Canada can make use of this, let me know and we can work something out (to cover the cost of shipping and customs that I've already paid).

Did you ever find out if the threads on your 2998 match the trilogy or 3861?

benderschweiz · Aug 25, 2023

I'd also be interested to know if there is a sapphire caseback which fits the Ck2998?

Euerology · Aug 30, 2023

Hi, can anyone measure the 1861 spiralwinder caseback gasket for me? Diameter and thickness.

I seem to have lost the gasket on mine and can only get approximate measurements from the caseback with my calipers. Wouldn't like to order a new full set just because of that. I have sent a message to spiralwinder with no reply yet..

Butik · Sep 9, 2023

Dear Colleagues!
I am bringing back this topic again hoping that maybe you will help me

Soon I will be getting the Tokyo 2020 Speedy, blue reversed panda version shown on attached photos.

I have reached out to spiral winder, with whom I did my previous FOIS modification and this is the reply I have received: "We are confident that the caseback will not fit the Tokyo 2020 Speedmasters. Some of our customers have already attempted to fit both the 3861 and standard Speedmaster casebacks to the Tokyo editions, with no success."

Would you have any idea why? Do you maybe have some alternative ideas where to go, what to buy, so that I can replace closed casebook with see-through one, which I strongly prefer...

Finalboss · Sep 24, 2023

Hi Butik, i have a tokyo 2020 rising sun and would be very interested in a clear case back as well so if you find out any more please let me know!

shinkansen · Dec 23, 2023

I am running into the exact same issue with my FOIS that @chipotlefire reported earlier. My watch is +10s/day with the original caseback, -10s/day with the spiralwinder sapphire, and restoring the original brought it back to its original rate. I also noticed that the hairline gap is bigger on the pusher/crown side than the other one, which makes me think the inner o-ring is too tall and hitting the stems. Just reached out to Spiralwinder and will see what they recommend.

nickjust · Dec 23, 2023

A watchmaker once told me that it can make a difference to the timing how tightly a case back is screwed down, @shinkansen I wonder whether that could be a factor here?

shinkansen · Dec 23, 2023

It definitely could be, I didn't screw in the case back fully and left a hairline gap (which also seems to be the case for other posters in this thread). The watch is still losing time - I want to try this without the inner o-ring to see if that's the issue here. That said, the magnitude of the difference (from gaining to losing 10 seconds) is crazy to me.

brokenblinker · Feb 16, 2024

I ordered a SpiralWinder caseback for my 3572.50. Removing 1mm of thickness sounds amazing!

1st frustration I found was lack of good instructions. The installation instructions just say "Fitment is simple - You will need to remove your old caseback and dust cover. Then, screw on the new exhibition caseback and enjoy the view! No spacers or additional parts are necessary!" Well, there is a gasket on the original sapphire caseback, and the one on the new caseback is a slightly different size (the ring diameter is smaller). I tried the following combinations:
- original gasket
- new gasket
- both gaskets
during various trial/error. I was never able to get the caseback to sit flush to even start the threads. I don't believe I want to attach it with NO gasket, as I assume that would greatly hurt my WR. I installed the original caseback and gasket and sent off an email to SpiralWinder and haven't heard back.

If I don't hear back (as many here seem not to), I guess I'll have no choice but to do a credit chargeback.

ErichPryde · Feb 16, 2024

@brokenblinker irony of ironies, going through the same thing here with a 1863 movement in a 311 (essentially the EXACT same watch you own except the generation). it won't sit flush! I've reached out to spiralwinder via email several times and have not received any response- the initial response I got was "absolutely it will fit" but when I ask how to make it fit- email silence since this weekend.

I'm wondering if the threading is different on the 1863 cases, since they are sapphire backs anyway. good to know I wasn't the only one!

B brokenblinker
I ordered a SpiralWinder caseback for my 3572.50. Removing 1mm of thickness sounds amazing!

1st frustration I found was lack of good instructions. The installation instructions just say "Fitment is simple - You will need to remove your old caseback and dust cover. Then, screw on the new exhibition caseback and enjoy the view! No spacers or additional parts are necessary!" Well, there is a gasket on the original sapphire caseback, and the one on the new caseback is a slightly different size (the ring diameter is smaller). I tried the following combinations:
- original gasket
- new gasket
- both gaskets
during various trial/error. I was never able to get the caseback to sit flush to even start the threads. I don't believe I want to attach it with NO gasket, as I assume that would greatly hurt my WR. I installed the original caseback and gasket and sent off an email to SpiralWinder and haven't heard back.

If I don't hear back (as many here seem not to), I guess I'll have no choice but to do a credit chargeback.

nickjust · Feb 16, 2024

@brokenblinker, I'm not sure these casebacks are intended to be used on the sapphire sandwich Speedmasters. The instructions your quote refer to the iron dust cover, which wouldn't apply to your Speedy. Is your model listed in the compatible references on the Spiralwinder website?