Malaysia Watch Forum
Main Forums => General Discussion - Modern Watches => Topic started by: terrenceterrence on April 16, 2011, 06:08:58 PM
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Why does some 7750 equipped watches wobble more than others?
Handled a few 7750 watches like a PAM, my Tudor 79280, Damasko and etc. but somehow the strength of the wobble are all different. At first i thought maybe the PAM 243 have a larger case and thus vibrates more..but i tried a Damasko DC56 which is roughly the same size as my Tudor, vibrates quite strongly too.
So it makes me kind of wonder why the differences? Anyone any idea?
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I would like to piggyback on ur q. Why does it wobble in the 1st place?
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It's not vibration, more like u can feel the movement .. aiya dunno how to explain lah..
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it only winds in one direction and when it freewheels in the non winding direction, it gives the wobble/vibration feeling.
but my question is why it it more pronounced on some watches and not others even though it`s the same movement]
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5100 also winds in 1 direction but it doesn't wobble as violent as 7750.
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It winds in one direction and freewheels in the other. The rotor is a large oscillating weight and it can reach very high speeds when rotating in its non-winding direction and this causes the wobble. Also the degree of wobble that you feel is dependent on where the movement is located relative to the strap point on the lugs. Fit also plays a part on the 'feel' of the wobble. Basically if the movement is on the same plane as the spring bars, you would not 'feel' the wobble. If your watch has a flatter case back, the wobble will also be less pronounced. I was told that the ETA 7750 needs 600 to 800 rotation of the rotor to fully wind.
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I think different brand has different fittings, level of customization, case thickness, material etc....
All of which contributes to different "feel" of the wobble.
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It winds in one direction and freewheels in the other. The rotor is a large oscillating weight and it can reach very high speeds when rotating in its non-winding direction and this causes the wobble. Also the degree of wobble that you feel is dependent on where the movement is located relative to the strap point on the lugs. Fit also plays a part on the 'feel' of the wobble.
Agreed. My Speedy Date doesn't wobble as much (not that I've had much experience with other 7750-based watches though)
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Sharing an excerpt from the article "The Fall and Rise of the Valjoux 7750" ,June 2008 Watch Time:
"There is much to admire about the 7750 and its offspring. These movements are famously precise and reliable. In fact, after they’ve been given careful fine tuning, the 7750 and its derivatives breeze through official chronometer tests.
Futhermore, the 7750 offer designers many options. They can choose to leave out the running seconds hand, the date display and/or the day indicator. The designer can dispense with the 12 hour counter or self-winding subassembly.
Critics so cite some drawbacks. Some watchmakers note the 7750’s relative thickness and large diameter, but these attributes are less problematic in this era of jumbo watches. And, in a watch with a transparent back, the 7750’s size is an asset. In addition, some wearers are conscious of the sound the rotor makes. It occurs because the large oscillating weight with its heavy metal segment can reach very high speeds when rotating in its non-winding direction. The sound is unavoidable, however, and shouldn’t be considered a defect.Others complain about the movement’s lack of exclusivity: about 200,000 units of the 7750 are made each year. Big as that number is, though, it isn’t enough to satisfy demand.
The shortage is likely to get worse this year because, in accord with its agreement with Swiss Competition Commission, ETA will start to reduce its deliveries of all its movement kits, including those for the 7750, in preparation for a total cutoff in 2010. ETA will continue to sell complete movements. About 75 percent of all mechanical movements in Switzerland are based on ETA movement kits, so this step will be a painful one for the firm’s customers.
Movement makers are developing substitutes for the 7750. The simplest is an exact replica. Since the patent for the 7750 has expired, nothing stands in the way of this project. Sellita is now hard at work on a clone of the 7750. It hasn’t been born yet, but it has been named; it will be called the SW 500. In the meantime, ingenious manufacturers in China are producing large numbers of rather coarse copies of the 7750 in various versions...."
personally for me, the wobble tells me that my PAMs are there. Sometimes I do kind of "miss" the wobble when I have the handwound PAMs on.
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Great read!
So its been a few years, has Selita finished their R&D of the "copy" yet?
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Great read!
So its been a few years, has Selita finished their R&D of the "copy" yet?
Yes bro, Sellita SW500 was launched at Baselworld 2010. It is IMHO a carbon copy of the 7750 with very minor changes. I think Invicta is using the SW500.
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Anyone owe a Sellita movement???
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Anyone owe a Sellita movement???
Me me me! My Oris Divers TT1 is running on SW200 ;D
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Anyone owe a Sellita movement???
Me me me! My Oris Divers TT1 is running on SW200 ;D
How is it compare to ETA? in terms of handling, feel, reliability???
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I remember reeading somewhere the Christopher Ward also used a Sellita movement.
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Should be ok as Selita use to work on ETA movement. In fact Selita use (or still is) ETA biggest customer.
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Should be ok as Selita use to work on ETA movement. In fact Selita use (or still is) ETA biggest customer.
Is it more robust? I am interested in particular of SW500
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Should be ok as Selita use to work on ETA movement. In fact Selita use (or still is) ETA biggest customer.
Is it more robust? I am interested in particular of SW500
I think is comparable to ETA, didn't see any complain so far.
Parts are not exchangable though.
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Anyone owe a Sellita movement???
Me me me! My Oris Divers TT1 is running on SW200 ;D
How is it compare to ETA? in terms of handling, feel, reliability???
too inexperienced and too early to tell....plus, i only have 3 watches, 1 on SW200, 1 on ETA 2892-A and 1 on 3135...so it's a lil hard to compare.
the SW200 runs +6 a day and the 2892 runs -3 without any particular resting position...
the SW200 date changes at 11:40pm and by 11:30pm it will be halfway between 2 dates, while my 2892 has no date...the 3135 changes 10 seconds after midnight.
the oscillating weight moves more freely on the 2892 compared to the SW200, hence better power reserve even if there's only slight activity with your wrist...can't comment on the 3135 since there's no display caseback and i don't wear it very often (can't wear to work cos my manager is into watches as well)
it takes more turn with the crown to fully wind the spring on the 2892 (>40 turns) whereas SW200 takes less than 35 turns before it starts clicking....3135 is similar to SW200 in this area.
the 2892 is quite loud during operation compared to the SW200, but then again could be due to the case design...the TT1 is a divers watch after all...to hear the 3135, you have to be in a quiet room and put it very close to your ear and breathe very slowly...
that's about all i observe in these few months that i've owned these watches :thumbsup:
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Anyone owe a Sellita movement???
Me me me! My Oris Divers TT1 is running on SW200 ;D
How is it compare to ETA? in terms of handling, feel, reliability???
too inexperienced and too early to tell....plus, i only have 3 watches, 1 on SW200, 1 on ETA 2892-A and 1 on 3135...so it's a lil hard to compare.
the SW200 runs +6 a day and the 2892 runs -3 without any particular resting position...
the SW200 date changes at 11:40pm and by 11:30pm it will be halfway between 2 dates, while my 2892 has no date...the 3135 changes 10 seconds after midnight.
the oscillating weight moves more freely on the 2892 compared to the SW200, hence better power reserve even if there's only slight activity with your wrist...can't comment on the 3135 since there's no display caseback and i don't wear it very often (can't wear to work cos my manager is into watches as well)
it takes more turn with the crown to fully wind the spring on the 2892 (>40 turns) whereas SW200 takes less than 35 turns before it starts clicking....3135 is similar to SW200 in this area.
the 2892 is quite loud during operation compared to the SW200, but then again could be due to the case design...the TT1 is a divers watch after all...to hear the 3135, you have to be in a quiet room and put it very close to your ear and breathe very slowly...
that's about all i observe in these few months that i've owned these watches :thumbsup:
Very informative :thumbsup: Thanks