aroma
521
Chronometer v non-chronometer - what's the difference?
A question for all you Omega experts:-
I'm nowhere near as experienced as some of you but I'm keen to learn anything I can. However, I struggle to see the benefit of spending a lot more cash on a certified chronometer when it seems that there is no clear advantage.
Amongst my collection, I have a 1964 Constellation with a chronometer rated cal 551 and a 1964 Seamaster with a non-chronometer cal 552. I know both movements are very similar and I believe that the 551 was tuned before being sent to the Laboratory for testing (incidentally, it was one of the famous 100,000) and that the chronometer rating was only valid then (i.e. 1964) but the Seamaster keeps time to within 6 sec/day and the Connie gains about 15 sec/day. OK, the Connie needs regulating I hear you say but just what is the physical difference between the two movements - does the 551 use better or different components to the 552 or is it just down to the tuning? - and if it is possible to tune non-chronometers to this level, what is the value in chronometers?
As always, thanks in advance for your input
Cheers,
Andrew
More posts:
Chronometer v non-chronometer - what's the difference?
A question for all you Omega experts:- I'm nowhere near as experienced as some of you but I'm keen to learn anything I can. However, I struggle to see the benefit of spending a lot more cash on a certified chronometer when it seems that there is no clear ...
well from a discussion with my watchmaker what I can remember is the following
The constellation and the rare seamaster certified chronometers had their balance wheel poised and regulated. I have rarely seen watchmaker nowadays poising the balance during an overhaul if not never of course there is also the meticulous oiling and regu...
Chronometer rating...
Andrew, certified chronometer accuracy is only at the time of testing and when the watch is sold shortly afterwards. When the watch has been worn for several years the accuracy may have become worse (not necessarily) and then the chronometer might behave ...
So are you saying that...........
there is no or little difference between the 551 and 552 movements Erich? Cheers Andrew
Yes, I think so...
Yes, I think so... after this long time it will not run within chronometer spec. unless it was very well cared for and you have a patient watchmaker to regulate it perfectly. But with Omega you can also reach the same accuracy with a non chronometer movem...
I've got all of my vintage non-chrono certified Omegas
all tuned and running to well-within COSC specs. As Georges says, a good watchmaker can do this.
But...I feel better when I have...
........chronometer. Let's have a look at a Non chronometer 565 and a chronometer. 564. basically there is no difference. but under the balance wheel of the 564, you see they drilled small holes to balance the wheel, the 565 has a clean wheel. It means th...
Ahh Haa - now I get it....................
so, it's just down to tuning after all. I had thought that there might be superior components in the chronometer. Thanks Andrew
Wait.
It applies to Omega in those days but if you go to zenith 135, you will see that they made all the 135 chronometers with special components and design. You can not find a Non-chronometer 135 ever and that's a big difference....
Actually not quite correct.... hoi...
Hi Hoi the Zenith 135 was designed from the ground up as a wristwatch chronometre movement, that being said... The last of the 135 were not marked chronometre on dial or movement. The finish was slightly economized .... but in my book it still a 135. Good...
I am with you...
Hi Bill, I am with you! I saw such an "unmarked" Cal. 135 watch recently in a sober screw down SS case... I also consider it a chronometer despite the missing "chronometre" on dial and movement. I suppose these have been the "last" movements of the produc...
Thanks Bill
Just because all 135's I have are chronometres , maybe I should buy a Volna
I have one somewhere, you should get one!
Hi Hoi I used to have three complete 135 , sold a mintb34 mm snap back to one friend and a 36 mm steel screwback to another and kept the steel 36.5 diameter captan case one for myself! Please post yours ... EsBill
Posting my Zenith 135 in here?
Hi Bill. Right now, I have 3 in my possession, this one looks best. It's a 37mm 18K rose gold.case. Hoi....
It's not only poising and regulating....
It was also about parts quality at the time of production. Omega only used the best, flaw-free parts for chronometers. The company used high magnification with overhead projection to sort parts according to quality. Only the parts that met standards for g...
heres the adjustment process in more detail
I just pulled out a piece I did on Omega chronometer adjustment that may be of use click click here
Couldn't have said it better than Desmond
Also, don't forget, there's the style factor - I personally love the extra chronometer script on the dial plus the piepan dials on the constellations.
Great question and Great answers posted .
Hello Aroma I saw the your post a few days ago... and I have been thinking about how to answer you.... others like Desmond gave some very straight forward answers. But I find the scope really was about the 552 vs 551 or 564 vs a 565 etc.... This is where ...
Yes Bill, the issue was ............
'what really is the physical difference between the chronometer graded movements and the equivalent non-chrometer movements - I was thinking particularly of the cal 551 v 552 as you say. Now I know that there was little difference other than that the chro...
your 551 sounds knackered to me so perhaps i should take it off your hands :)
its the right year for my collection so i'd begrudgingly let you pass it on to me despite it obviously needing a serious overhaul in all seriousness, its entirely possible to get a non cosc movement to work well within cosc levels. i like to adjust them m...
Nice try but..........
no deal. It has taken me ages to source my vintage Omega 'collection'. I'm so fussy - particularly about dials. As I said in a previous post, you can replace.service all the mechanical bits but you can do little with a damaged dial. Anyway, just to whet y...
very nice. one day i'll...
very nice. one day i'll get me a connie with a correct dial. mine is a redial which i can live with, but would rather get a good 'un. best G
Here are a few comprisons of 30mm movements:
Cal. 269 at left, 30T2(SC)rg at right: just visually, polished winding wheels, polished and shaped teeth, polished and beveled screwheads, finer anglage deeper-cut teeth (require greater precision in setup), thinner and beveled wheels and spokes: Lots of ...
OK, but.........
these are presumably a 30T2 and a 30T2Rg chronometer which I know is a fabulously made piece and yes I want one!! But is it the same for say the 551s and 552s or any of the 'later' chronometers from the 1960s hey days? I would have thought that it would h...
