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Can't resist to open my new vhp GMT. It's a Longines L287.2 / eta 56.411. Interestingly the spacer ring is plastic and there are finger prints on the brass plate. Not a deal breaker since it's only 1200usd retail and I got some discount from New Zealand AD, but a little disappointed. The watch looks and runs beautifully.
 

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Can't resist to open my new vhp GMT. It's a Longines L287.2 / eta 56.411. Interestingly the spacer ring is plastic and there are finger prints on the brass plate. Not a deal breaker since it's only 1200usd retail and I got some discount from New Zealand AD, but a little disappointed. The watch looks and runs beautifully.
A few months ago I posted a photo of my V.H.P three hander + date in the "Pictures of notable HAQ movements and watches ..." thread, maybe you should too, so we have a database entry for the GMT as well.
I too had a partial fingerprint on the movement, it's quite probable that the same person assembled both movements. Would be cool to compare the prints.:)

Anyway, it's my most expensive watch, also my grail and I couldn't be any happier with it (despite the fingerprint).
IMG_2859.jpg
 

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"NO (0) JEWELS" just killed any desire I had for the VHP.

But thanks for the photo, OP!
 

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Huchiz,

Thank you for sharing a picture of the VHP movement. It's a bit disappointing that the movement is held in place by a plastic ring, but I guess Longines had to keep cost low to reach their retail price range. Enjoy your watch in good health.
 

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The use of stepper motors in quartz movements has essentially obviated the need/benefit of jewels.

HTH
Can this depend on who made the movement and how exactly?

Miyota no jewel quartz is known to run forever. Including my own watches.

Ronda (Swiss) 0 jewel break down in a way consistent with wear.
I had a 2-year old 763 that started to stall every few hours even with a new battery.
I see unused watches with Ronda 0 jewel sold for parts on ebay. Failed while in store. All with the same pattern: watch stops and needs to be hit to start again to run for a few hours.

I am of very low opinion about Swiss Ronda company, but their failure rate makes them a great test object.
If one had enough examples of jeweled vs unjeweled Ronda failures, these could certainly help to draw conclusions about quartz watches vs jewel count.
 

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Can this depend on who made the movement and how exactly?

Miyota no jewel quartz is known to run forever. Including my own watches.

Ronda (Swiss) 0 jewel break down in a way consistent with wear.
I had a 2-year old 763 that started to stall every few hours even with a new battery.
I see unused watches with Ronda 0 jewel sold for parts on ebay. Failed while in store. All with the same pattern: watch stops and needs to be hit to start again to run for a few hours.

I am of very low opinion about Swiss Ronda company, but their failure rate makes them a great test object.
If one had enough examples of jeweled vs unjeweled Ronda failures, these could certainly help to draw conclusions about quartz watches vs jewel count.
I'll be more specific.

For movements like those used in the new Longines Conquest VHP watches, all hand movement is driven directly by a stepper motor. There is no gear drive train. No gears = no gear shafts = no shaft bearing surfaces = no requirement for a jewel to add life to the bearing surface.

In other movements that do have gear trains, then yes, jewels used at the gear shaft bearing surfaces might reduce wear and prolong life.

In the context of this thread about a stepper motor driven movement, my statement stands.

HTH
 

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I'll be more specific.

For movements like those used in the new Longines Conquest VHP watches, all hand movement is driven directly by a stepper motor. There is no gear drive train. No gears = no gear shafts = no shaft bearing surfaces = no requirement for a jewel to add life to the bearing surface.

In other movements that do have gear trains, then yes, jewels used at the gear shaft bearing surfaces might reduce wear and prolong life.

In the context of this thread about a stepper motor driven movement, my statement stands.

HTH
Interesting. Do they actually use not the standard Lavet-type stepping motor?
https://en.wikipedia.org/wiki/Lavet-type_stepping_motor
 

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Interesting. Do they actually use not the standard Lavet-type stepping motor?
https://en.wikipedia.org/wiki/Lavet-type_stepping_motor
Yes they do, but...
I'd add to what gaijin said that it actually has a gear train, however, not in the sense that a mechanical or normal quartz movement has. "Classic" movements use one motor (or mainspring) to drive a gear train that has numerous reductions, like a gearbox, to essentially convert seconds to minutes and minutes to hours. This adds a lot of torque (less in the case of quartz, more in the case of mechanical movements) on the gears and hence a considerable lateral force on the gear pivots (as the gears try to push against each other), which increases friction and wear.
The Longines (and other so called "fly-by-wire" quartz movements) has a separate motor to drive each hand, without any direct interactions between the hand's gear trains, thus reducing torque (as each motor drives only one hand, without needing to drive all three hands, as well as the gears needed to link them) and friction, because the only resistance in this case is the weight of one hand.
The Seiko 9F for example uses only one motor, with the aforementioned gear train, and (while admittedly being jeweled) still manages to go 50 years without a service (as per Seiko's specs). This is because compared to a mechanical movement, the frictions in even a "classic" quartz movement are so low. Fly-by-wire movements manage to reduce this already minimal amount of friction to an almost negligible amount. Jeweling such a movement would be overkill.
 

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Besides being overkill, also a waste of money. Let's not forget that the new VHP's have the same accuracy as limited edition GS 9Fs that cost $5k, while being only in the neighborhood of $1k. I'd say, regarding HAQs, you can hardly get more bang for your buck...
 

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The Seiko 9F for example uses only one motor, with the aforementioned gear train, and (while admittedly being jeweled) still manages to go 50 years without a service (as per Seiko's specs).
I have owned two GS cal 9Fs and whilst the promotional material may have boasted of a 50 year service interval, the actual recommended frequency per spec was, I believe, five years. I don't know if the five year service would involve a movement strip-down or just a clean-up, battery change, hand alignment, seal replacement, diagnostic test and perhaps a touch of rate regulation.

I can just imagine how the marketing department must have irritated the heck out of the after sales team with that 50 year line.
 

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Yes they do, but...
I'd add to what gaijin said that it actually has a gear train, however, not in the sense that a mechanical or normal quartz movement has. "Classic" movements use one motor (or mainspring) to drive a gear train that has numerous reductions, like a gearbox, to essentially convert seconds to minutes and minutes to hours. This adds a lot of torque (less in the case of quartz, more in the case of mechanical movements) on the gears and hence a considerable lateral force on the gear pivots (as the gears try to push against each other), which increases friction and wear.
The Longines (and other so called "fly-by-wire" quartz movements) has a separate motor to drive each hand, without any direct interactions between the hand's gear trains, thus reducing torque (as each motor drives only one hand, without needing to drive all three hands, as well as the gears needed to link them) and friction, because the only resistance in this case is the weight of one hand.
The Seiko 9F for example uses only one motor, with the aforementioned gear train, and (while admittedly being jeweled) still manages to go 50 years without a service (as per Seiko's specs). This is because compared to a mechanical movement, the frictions in even a "classic" quartz movement are so low. Fly-by-wire movements manage to reduce this already minimal amount of friction to an almost negligible amount. Jeweling such a movement would be overkill.
That's what I thought. Almost: one thing is a bit unclear, the Lavet stepper is commonly described as a unidirectional motor.

But on my Citizen and Oceanus quartz watches hands can rotate both ways.

Did manufacturers figure out how to drive Lavet backwards by arranging clever pulse sequences?
Are they using a modified Lavet?
 

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"NO (0) JEWELS" just killed any desire I had for the VHP.
Then you should look for those watches which have more jewels than bearing points. They are usually also reasonably cheap.

Like explained already, "dumb" quartz watches need jewels, while "smart" quartz watches like V.H.P. do not, because there is no gear train in them. Apple Watch also does not have jewels, your smart phone does not either, even though it also shows time.
 

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So, 4 motors on the GMT: H:M:S:GMT. What drives the date wheel? A gear or ratchet or something connected to the 24 hour hand?
At least in my watch the seconds hand stops when the date is advanced. At least when the watch is started from the sleep state. If I remember correctly also when date changes? Maybe the power is diverted from there?
 

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So, 4 motors on the GMT: H:M:S:GMT. What drives the date wheel? A gear or ratchet or something connected to the 24 hour hand?
The motors are :-Seconds, Minutes and hours (geared together), Date and GMT
I believe that all of the hands are geared to the motors because they are 'large-angle' steppers.
Direct-drive small-angle steppers would be perfect, but I think that they would cost too much and be too big.
I guess that ETA have done a lot of work on these motors, they are very small and (unlike standard Lavet motors) reversible.
 
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