SH21 movement and number of jewels

[ExpatTarheel]

Hi all,
I'm thinking about getting a CW watch with the SH21 movement. I'm confused though. The C8 Power Reserve Chronometer has 27 jewels while the C65 Trident Diver SH21 Limited Edition has 33 jewels. Shouldn't the number of jewels be consistent between different watches with the same movement?

Thanks in advance!

[downer]

Welcome to the forum.

The C8 uses a manual version of the SH21 whereas the C65 is an automatic. I guess this explains the different jewel count.

More information can be found in the archive... https://cwarchive.knack.com/cwarchive#m ... c93b45106/

[ExpatTarheel]

Welcome to the forum.

The C8 uses a manual version of the SH21 whereas the C65 is an automatic. I guess this explains the different jewel count.

More information can be found in the archive... https://cwarchive.knack.com/cwarchive#m ... c93b45106/

Thanks Richard! I thought that might be the case but I wasn't sure. I have to admit the C8 Power Reserve is calling to me.

[MarkingTime]

Being of modular design the SH21 can have various complications added, so affecting the number of jewels.

[ExpatTarheel]

Being of modular design the SH21 can have various complications added, so affecting the number of jewels.

I'm hoping for a GMT version with a quick-set hour hand.

[downer]

I'm hoping for a GMT version with a quick-set hour hand.

You can rest assured that CW have been made fully aware of the NEED for that complication. I mention it every time I get an opportunity!

[ExpatTarheel]

I'm hoping for a GMT version with a quick-set hour hand.

You can rest assured that CW have been made fully aware of the NEED for that complication. I mention it every time I get an opportunity!

Keep mentioning it!

[downer]

I'm hoping for a GMT version with a quick-set hour hand.

You can rest assured that CW have been made fully aware of the NEED for that complication. I mention it every time I get an opportunity!

Keep mentioning it!

I will - although I'm not sure they are listening.

I really believe an affordable quick-set GMT would be a winner - particularly with a 5 day power reserve.

[H0rati0]

There's more than quick setting to a "proper" GMT watch. While independent setting of the 24hr display and normal hour hand are necessary, the date also has to be coupled to the normal hour hand so that when travelling from east to west the date moves backward when the normal hour hand crosses midnight backwards as one adjusts local time. The ETA/Sellita movements do not do GMT properly, they just allow monitoring of a second/third time zone from the home time zone, so a proper SH21 based GMT complication would be very cool, though likely expensive.

[ExpatTarheel]

There's more than quick setting to a "proper" GMT watch. While independent setting of the 24hr display and normal hour hand are necessary, the date also has to be coupled to the normal hour hand so that when travelling from east to west the date moves backward when the normal hour hand crosses midnight backwards as one adjusts local time. The ETA/Sellita movements do not do GMT properly, they just allow monitoring of a second/third time zone from the home time zone, so a proper SH21 based GMT complication would be very cool, though likely expensive.

Completely agree on all the counts you mention here, especially the price. If CW can give me a true GMT watch for 1/4-to-1/3 the price of a Rolex GMT Master II though, I'll gladly pay it!

[timor54]

... The ETA/Sellita movements do not do GMT properly, they just allow monitoring of a second/third time zone from the home time zone, ...

Largely true but there are exceptions. The ETA C07.661 is a proper GMT calibre with an independent hour hand that advances/retards the date as it is wound past 24hrs. It works exactly in the same way as the Rolex/Tudor/Grand Seiko GMT calibres, together with a lack of quickset date which is the downside of such calibres.

Swatch use it in the Certina DS-Action GMT Powermatic 80 which retails for about £900 or so. I’ve played with this and it’s very impressive for its price, just a little bit chunky in size.

I think it may also be used by Mido and possibly Hamilton? But basically it appears to be only available to internal Swatch brands.

[H0rati0]

... The ETA/Sellita movements do not do GMT properly, they just allow monitoring of a second/third time zone from the home time zone, ...

Largely true but there are exceptions. The ETA C07.661 is a proper GMT calibre with an independent hour hand that advances/retards the date as it is wound past 24hrs. It works exactly in the same way as the Rolex/Tudor/Grand Seiko GMT calibres, together with a lack of quickset date which is the downside of such calibres.

Interesting, I wasn't aware of that calibre.

However, while never saying never to an SH21 GMT - particularly in a C65 version, I already own a Ulysse Nardin GMT that does everything, including quick set date. Maybe some would say it cheats because it uses a digital 24hr display, but for travelling I find it perfect, the Grande Date being so useful at my age!

[KornSaksakorn]

Look forward to "convenient" GMT + second-hand subdial + power reserve indicator + sapphire caseback in the package of SH21 automatic.

[Commisar]

There's more than quick setting to a "proper" GMT watch. While independent setting of the 24hr display and normal hour hand are necessary, the date also has to be coupled to the normal hour hand so that when travelling from east to west the date moves backward when the normal hour hand crosses midnight backwards as one adjusts local time. The ETA/Sellita movements do not do GMT properly, they just allow monitoring of a second/third time zone from the home time zone, so a proper SH21 based GMT complication would be very cool, though likely expensive.

Ehhh, most people see anything with a GMT hand as being a true multi time zone watch, as it is.

My Citizen Nighthawk GMT actually has a jumping hour hand

This is essentially saying a "real" GMT watch needs to be $3500+

Sent from my SM-G973U1 using Tapatalk

[Amor Vincit Omnia]

Ehhh, most people see anything with a GMT hand as being a true multi time zone watch, as it is.

My Citizen Nighthawk GMT actually has a jumping hour hand

This is essentially saying a "real" GMT watch needs to be $3500+

I agree with you that anything which has a fourth 24h hand pointing to a second time zone is a GMT watch.

What I would say is that if you want a movement that “gives you a much more convenient way to change settings”, rather than calling it a “true GMT”, you are going to have to pay a premium. I think I said that earlier on another thread.