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Discussion Starter · #1 · (Edited)
I do my watch collecting, service and repair at a slow pace and
I've had this watch on my bench for over a month. It is presently in a dismantled
state and has been waiting for me to take pics of the various parts as I
think the watch is worth a picture thread.
It is a Kew observatory class 'A' certified chronometer.





Most collectors of watches will know what a chronometer is as we have
heard of C.O.S.C, the body which guarantees a standard of accuracy
and certifies chronometers.

This tradition of certifying a watches accuracy is steeped in history and
hails from a far flung age when lives depended on the accuracy of the
time piece.
In the early days a chronometer was used onboard ship, and used
in conjuction with a sextant then a ships longitude could be found at sea.
The accuracy at which longitude could be found was determined directly
by the accuracy of the ships chronometer, especially its ability to keep
accurate time over long periods and varying temerature ranges.
Only a few seconds error and the ships position would be off by a few miles
...the more accurate the chronometer then the more accurately the ships
position could be calculated, simple as that.

Because the accuracy of the chronometer was so important to a ships
navigation and safety at sea, astronomical observatories were charged
with the testing of timepieces.
Various observatories around the world set up facilities to test
chronometers and one of these was the Royal Observatory at Kew.
Chronometers tested at the Kew observatory had to go through very
stringent testing with testing lasting 44 days.

This watch is an English lever, 3/4 plate movement with going barrel,
made by George Edwards of london & Glasgow, Late 19thC and is 44mm Dia.
I made a post about this watch a while ago but only recently decided
to service it with the intent of casing it up somehow, to protect it
as it has lost its original case to the scrapman.

Thousands of English lever movements of this 3/4 plate type and of
varying spec of jewelling and escapements have been orphaned and are
to be seen all to regularly on E-bay. I'm reluctant to say of
'varying quality' because even low spec seven jewelled English levers
seem to be built with the same regard to quality of finish as its
higher spec cousins i.e gold gilt plates, cocks and bridges, highly
polished springs, pinions, arbors and facets etc.

The attention to detail and quality tends to be much the same whether
one has a seven jewelled example in hand or a high spec 19 jewelled
version such as this example.
Having said that, quality can in a lot of cases be hidden and is not
readily apparent. This quality is expressed in the carefull selection of
materials and parts necessary to produce a high grade watch which would be
capable of excellent time keeping, i.e Very best quality selected hairspring;
Very best quality jewels carefully selected and polished to the highest
standard etc.

This watch can safely be said to fall into the High spec, top grade for
this type as it has been chronometer certified class 'A' at the
Kew Observatory. The top grade especially selected parts and materials,
the extra work required by the master 'Springer Adjuster'and the cost of
certification would have placed this watch into the very expensive price
bracket when new.
My hope is that I can convey the excellence of craftsmanship and quality of
the high class engineering required to make such a watch which could pass these
stringent tests.

The watch would have started as an ebauche such as the one pictured here.





These rough ebauches or 'Grey' movements as they are sometimes called were
produced on mass in centers of production such as Prescott in lancashire.
From this ebauche the watchmaker could make a plain seven jewelled pocket
and everything in between up to the highest grade 19 jewelled levers.

Disassembly was straightforward with little problems. The dial, a Swiss replacement,
had been fixed with shellac by a previous repairman. Shellac is 'the' watchmakers
glue and presented me little problem unsticking it by simply disolving the shellac
with alcohol, methylated spirits in this case.



As I dismantled and cleaned the various components of the watch I carefully
examined the parts and it soon became apparant that the watch was in an excellent
condition with no repair work required anywhere, as far as I could tell.
Here are some pics of the lever, escape and balance. Note the lever is slotted at its
tail, this type is called the 'tuning fork' lever and is documented in old books but
is the first time I've actualy seen one.
I assume the 'slots' function is to reduce the mass therefore the inertia of the lever,
it might also facilitate the levers poise.
Note the Saphire stones beautifully set into the slotted steel pallet slits.
This 'concealed' method of securing the 'stones' is peculiar to English watches
but I have seen it in some Swiss side levers...looking at the pallets from most
angles you'ld be forgiven for thinking they are steel as the stones are effectively
hidden.






The balance is a cut compensated balance loaded with gold compensation and timing
screws. It is, unusually, for an English ratchet lever, fitted with a double roller
table with Saphire roller jewel (English watches of this type usually have a single
roller table).



The hairspring is unmolested and pristine and is pinned to a polished steel 'block'
collet in the manner of very best English work.



The center and third wheel. The finish to the spokes and internal angles could
be better as they have been left unbevelled, but the form and finish of the teeth,
the pinions and arbor are first class. The use of gold in these wheels is of a practical
concern rather than aesthetic as gold has excellent low friction properties, ie it
is a naturally slippery substance.





To be continued........
 

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No, but I did it for you.

Marine chronometers are fascinating pieces of machinery. I think they're just amazing. To think we achieved THIS level of timekeeping accuracy 200 years ago...
 

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Great post... Like the detail you have gone into when describing the parts.... Eventhough I am a novice when it comes to movements and their workings...

I look forward to part 2
 

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I learned something today. Gold is a virtually frictionless metal. I didn't know that. So THAT'S why they put it in watches...
 

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thanks for sharing your hard work, always great to see post like these. if i had a go like this my final picture would be the watch bits in a bin lol.
 

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Observatory Competitions

Wonderful post Radger! A great topic that I discovered, like you, following ownership of an Observatory Chronometer (of the Swiss variety). Your description of the movement's qualities is very inspiring.

If I may correct a slight inaccuracy with your story...
It is true that the Royal Observatory, Greenwich, organized the first timing competitions in 1766. The Swiss followed in 1772 at the Geneva Observatory. Geneva actually introduced the first points-based annual competition in 1874.

All Observatory contests, whether in England, Switzerland, France, Germany or the USA, were of 45 days duration. Timepieces that achieved a base level of 2/3 available points were granted a Bulletin de Marche (Class A certificate at Kew). Those that performed very well could enter the Grand Prix competition and the winners were given 1st, 2nd, 3rd Prize or Honorable Mention. Observatory trials unfortunately ceased when the quartz movement made accuracy a certainty.

The current COSC standard is a considerably dumbed-down process of 16 days testing; this is perhaps where your reference comes from. Observatory trials have reawakened with the interest in mechanical movements. In 2009 a Swiss/French competition was held and another is scheduled for the fall of 2011. Of the 16 wristwatches subjected to 3 sets of standard 16-day COSC trials conducted a three locations, six failed.

I can't quite read the number of points your movement received...is it 76.6 or 78.8? FWIW, the tests were not standardized so it is not possible to compare results between Observatories...something I think they did on purpose! Kew Observatory chronometer test ledgers are presently kept at the Greenwich Observatory Museum and they will provide an extract upon request. PM me for contact info if you wish :-!
 

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Re: Observatory Competitions

A wonderful thread. 78.8 marks was not bad at all, very few watches ever scored over 90.
 

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Re: Observatory Competitions

This thread is a great example of why many of us are here. Thanks to all!
 

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Re: Observatory Competitions

I am feeling confused. Our previous discussions would have labeled this as a half chronometer. Obviously being Kew certified implies something else.

Can you please take another photo of the lever, the slot in particular. The inside of the cut looks makes the lever look laminated - which seems odd considering the outside.

I enjoyed that post.
 

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Tick talk can you please provide more info about swiss/french competition? Maybe a link... Im reluctant to learn more
 

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Re: Observatory Competitions

Our previous discussions would have labeled this as a half chronometer.
Gosh, I'm not sure what a half-chronometer is...can you please explain? The term demi-chronometre was used by the Swiss observatories to reference a movement that was submitted for tests but was withdrawn prior to the full 45 days. It was more a marketing ploy as these pieces would not receive a certificate.
 

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Tick talk can you please provide more info about swiss/french competition?
So, in 2009 the Concours International de Chronometrie timing competition was undertaken to celebrate the 50th anniversary of the Museum of Horology at Le Locle, Switzerland. The competition was conducted in three stages, involving four locations! The watches started at the Besancon Observatory in France, where they underwent the standard 16-day COSC trials. They were then shuttled to COSC headquarters in Biel, Switzerland, where the 16-day trials were repeated. Then followed a side trip to Le Locle where the watches were subject to shock and magnetism stresses before being sent back to Biel for a third round of tests following the standard COSC formula. The shock and magnetism elements were new to Observatory trials and were intended to update the procedure for the 21st Century.

The 2009 competitions did prove that tourbillons are more than just a pretty face with JLC taking 1st and 2nd prizes using tourbillon movements. The contest is scheduled to be repeated in 2011 and I can only hope that more manufacturers participate with serious intentions. Long live the quest for mechanical perfection! Here is a link to the site: Concours de chronométrie, however it doesn't communicate much.
 

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Discussion Starter · #16 ·
Re: Observatory Competitions

Thank you for the kind words fellas, when I can get back to this watch in good daylight, I'll
put it together and take some pics of assembly-I need daylight for the pics.


If I may correct a slight inaccuracy with your story...
It is true that the Royal Observatory, Greenwich, organized the first timing competitions in 1766. The Swiss followed in 1772 at the Geneva Observatory. Geneva actually introduced the first points-based annual competition in 1874.

All Observatory contests, whether in England, Switzerland, France, Germany or the USA, were of 45 days duration. Timepieces that achieved a base level of 2/3 available points were granted a Bulletin de Marche (Class A certificate at Kew). Those that performed very well could enter the Grand Prix competition and the winners were given 1st, 2nd, 3rd Prize or Honorable Mention. Observatory trials unfortunately ceased when the quartz movement made accuracy a certainty.

The current COSC standard is a considerably dumbed-down process of 16 days testing; this is perhaps where your reference comes from. Observatory trials have reawakened with the interest in mechanical movements. In 2009 a Swiss/French competition was held and another is scheduled for the fall of 2011. Of the 16 wristwatches subjected to 3 sets of standard 16-day COSC trials conducted a three locations, six failed.

I can't quite read the number of points your movement received...is it 76.6 or 78.8? FWIW, the tests were not standardized so it is not possible to compare results between Observatories...something I think they did on purpose! Kew Observatory chronometer test ledgers are presently kept at the Greenwich Observatory Museum and they will provide an extract upon request. PM me for contact info if you wish :-!

Thank you for correcting me regards the testing duration, I picked up that snippet from the internet
and I should have known better. Checking in my books I'd certainly agree with you that observatory
competitions all lasted for the same duration.

I read on the watchmaking forum that these observatory trials had re-awakened, in fact the thread
was started by WUS member Clock40man a U.S watchmaker who's watch has been entered into the competition.
He deserves to be congratulated being the only student watchmaker in the U.S to have a watch accepted.

https://www.watchuseek.com/f6/october-2010-day-life-nawcc-school-horology-student-529374.html

I knew that records were still held and will P.M you requesting further info on whom I contact, thanks.

You have a V&C Observatory Chronometer!!! wow!!

Erick H said:
A wonderful thread. 78.8 marks was not bad at all, very few watches ever scored over 90.
78.8 marks wasn't bad at all for an English lever with Bi-metallic balance, I don't think scores started hitting the nineties untill the Guillaume balance was used, although a pre Guillaume
tourbillon or Karussel watch might have acheived this.
Spring detent chronometer escapements could easily achieve 90 points I suppose, but they
are a different kettle of fish.

For a watch to achieve 80 points and be classed especially good here is a typical result.

The average variation of rate ......................... a=0.41 secs per day
The avg change of rate with change of position. b=1.73 sec per day
The avg change of rate per one deg F.............. c=0.073 sec day

the points awarded using convoluted formulae would be
a 31.8 points+b 33.1 points+c 15.1 points=total score 80 points.

Trim said:
I am feeling confused. Our previous discussions would have labeled this as a half chronometer. Obviously being Kew certified implies something else.

Can you please take another photo of the lever, the slot in particular. The inside of the cut looks makes the lever look laminated - which seems odd considering the outside.
Trim, this would have been termed a Semi-chronometer a hundred years ago as semi-Chronometer
is an archaic term which described a lever watch with elements of the detent chronometer escapement
such as a compensated balance.
If a watch has a Kew certificate then you can call it a chronometer, whatever the escapement.

Yep the pics are not to good especially after re-sizing and re-compressing to conform to forum requirements only to see them re-sized again by the forum...they've definately lost a lot of definition. The lever is not laminated .
Here is another pic of the lever which can be zoomed...




Thanks again for the positive comments and when I get back to the watch I'll update the thread.
 

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Discussion Starter · #17 · (Edited)
Re: Observatory Chronometer, English movement PART 2

I managed to get back to this movement and took some more pics during
re-assembly.
Here is the dial side bridge showing the endstones cleaned and ready for
lubrication and another showing the bridge with the capped stones lubricated
and assembled.
This bridge carries the fourth wheel pivot, the capped jewels are the escape
wheel, lever and balance pivot holes. Note that English watchmakers marked
the individual capstones with a punch mark to the rim so that correct
replacement is facilitated.








Here we have the parts ready to be assembled dial side, this watch is pendant
wind, pin set with rocking bar lever.




And here assembled dial side winding and setting mechanism and dial side bridge.




A bit of luck here.
On removing the mainspring, I found it to be in a fairly poor condition.
It was 'set' ie it has lost a fair bit of its springiness.

A weak mainspring is not so good for timekeeping, a spring such as this might
give a good amplitude to the balance when fully wound but would quickly fall
off after a few hours resulting in a variable 'rate' as the day progressed.

The luck part is I actualy had an exact size in stock. With a mainspring
there are critical measurements to obtain the correct size and strength and
despite having hundreds of springs of various sizes, I usually find that I have
to send out for a correct replacement.




Here is the old spring alongside the new spring, for those who were wondering
the difference between a good spring and a 'set' spring.




The going barrel is fitted with Geneve stopwork. This simple mechanism allows
the spring to be set up so that its useable range is more even and uniform. The
extremes of a fully wound and a fully wound down spring are taken out of the
equation. Basicaly, the release of power from the spring to the train is smoother
across its torque curve throughout the day.



The stop work is set up with a half turn of the spring and limits the the spring
to four full turns of winding.



Here is the btm plate dial side down




Here it is with the train in position.

The going barrel is the first wheel in the watches train and is sometimes called
the great wheel but most commonly just called the barrel.

The center wheel is driven by the barrel and is called the second wheel. The second
wheel drives the third wheel which in turn drives the fourth wheel and that is a
watches 'train'. The subseconds hand is attached to the fourth wheel arbour.








Here the top plate is fitted. The train runs beautifully and the watch is ready
to accept the escapement.




Here is a pic of the full dialside assembly.




At this stage I spent a while hunting down a suitable replacement dial for the
to-small, Swiss dial which the watch had acquired.
Here is a quick snap of my neat and tidy bench.
The movement to the left of the Kew watch had to donate its dial to the cause.




The next two pics show a comparison of the unamed dial donor movement, and the
Kew watch.
I'd say from the same Ebauche manufacturer both marked as 16.1 but one
is Savonette as opposed to Lepine.
The Lepine layout has the winding stem set at twelve o-clock as opposed to Savonette
which has the stem position at three o-clock.The kew watch is the Savonette.






And that's as far as I've got with this watch, but I will update when I complete
the re-assembly. I want to compare the escapement of the dial donor watch with the
Kew watch, the donor is also 19 jewels and as can be seen, is very similar.
 

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Re: Observatory Chronometer, English movement PART 2

Again, I really enjoyed reading and seeing the assembly...

You made it seem quite simply.... when, In reality, Im sure its not!

I look forward to seeing the finished article!
 

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Re: Observatory Chronometer, English movement PART 2

Brilliant!! One of the most enjoyable reads this week, thank-you so much :) FWIW, your pictures of the Geneva Stopworks illustrates how it inspired, according to the factory, the Maltese Cross symbol used by Vacheron & Constantin. It appears in their trademark beginning in 1880.
 

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Re: Observatory Chronometer, English movement PART 2

Looking forward to the completed watch!
Your bench has a level of tidiness similar to what I can see in front of me right now... A quick count: 12 pocketwatches, one UG wristwatch, four containers with movements, one pocket aneroid barometer and altimeter, 2 dials, 2 unused display back cases, two NOS mainsprings...
 
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