Help Dating Atmos Clocks - with fotos

Discussion in '400-Day & Atmos' started by Rob_GER, Jun 9, 2020.

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  1. Rob_GER

    Rob_GER Registered User

    Jun 9, 2020
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    #1 Rob_GER, Jun 9, 2020
    Last edited: Jun 9, 2020
    Could you please help with Dating my Atmos Clocks, the first one S/N549033 probably from late 1982 or early 1983. It is Caliber 526-5, it has a silver colored casing. My Question regarding the case what material is the plating? Would it be rhodinium or nickel or chromium?

    The second Atmos S/N 23717 is Copper colored (or is it rosegold?) it has the Serial number on the top, according to the info I found in this Forum it should be a Atmos 2, however the pendulum is a Typ B (with dimpels and not black Stripes), It has blue screws and the Adjustment regulater knob towards the front. I wonder how many Clocks were produced plated in Copper at the time?

    Thanks for your help!

    Atmos_SN23717..JPG SN549033_front.jpg SN549033_side.jpg
     
  2. new_hampster

    new_hampster Registered User

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    549033 - your dating is correct. This is in Lebet's 'Living On Air', #5852, "silvered cabinet, silvered background dial...gold-plated movement, catalogued 1979-84". I have 5465xx, and it is identical, and has bellows date of 8.1.82 (Jan 8, 1982).

    23717 - would be late '49/early '50. This is a transition clock, moving from the Atmos II to the 519. During this period, most had the front-facing adjuster. I own 220xx with front adjuster and the Atmos II style balance. John Hubby may be able to provide more detail.
     
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  3. Rob_GER

    Rob_GER Registered User

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    Thanks new_hampster for your infos, yes it would be great if John Hubby or Mun Chor Weng could add something to it!
     
  4. MUN CHOR-WENG

    MUN CHOR-WENG Registered User

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    I also have a copper colored Atmos II s/n 17966 which JLC dated it as having been made on 2nd April 1947. Most probably yours was made a few years later, quite possibly within the time frame mentioned above by new_hamster.
    Most Atmos II produced up to the late 1940s were equipped with rear facing regulating adjuster.
    The adjuster was positioned above the bellows cover with the regulatinig knob sticking out just beyond the edge of the bellows cover. This creates a problem when the cover of the clock is lifted or replaced as there is very little clearance between the knob and the base of the cover causing it to rub against each other. At the same time a similar situation occurs in front of the clock with the base of the cover rubbing against the bezel of the clock causing some scraches on the upper part of the bezel.
    I believe it is because of this prolem that led JLC to change the position of the regulating adjuster to the front clock . This arrangement certainly solved the problem mentioned earlier and it was used for a short period durinig the tail end of the Atmos II production.
    With the introduction of the Atmos III in June 1950 a lever type of regulation located at the top of the movement was introduced and this arrangement is still in use.
    Pictures of my copper coloured Atmos II are shown below.

    Mun C W

    IMG_2682.JPG IMG_2705.JPG IMG_2692.JPG IMG_2509.JPG
     
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  5. Rob_GER

    Rob_GER Registered User

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    Thanks Mun for the Information and nice pictures of your clock!
     
  6. MUN CHOR-WENG

    MUN CHOR-WENG Registered User

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    Hello Rob_GER,

    In addition to what I have posted above, I like to add the following pictures and information.
    As can be seen in the pictures below the length of the front facing regulating knob is quite short thus avoiding the base of the clock cover rubbing against it during lifting or replacing the cover. It is unclear the reason the regulating knob in this front position was only used for a very short period in the Atmos II and was not used in the Atmos III. Maybe the position of this regulating knob breaks the bi-lateral symmentry of the clock and that might have prompted JLC to position the new regulating lever system starting with the Atmos III to the top center of the clock to give it a more pleasing symmentrical appearance.

    The clock shown with serial number 235959 is an Atmos II as can be identified by its wide front plate that obscures the first wheel when view from the front. JLC has dated the clock as having been made on 30th June 1952 which is a full two years after the Atmos III was introduced. So there is some overlapping.

    Mun C W

    20160217_112342.jpg 20160217_112122.jpg 20160217_113047.jpg
     
  7. Rob_GER

    Rob_GER Registered User

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    Hi Mun,

    your last post is very interesting and raises question on my side ...
    Your Atmos II was made 242 units after my Atmos, John Hubby mentioned in a PM that mine would have been made in early 1950. I cannot imagine that if yours in from 1952 that they only produced about 120 clocks a year. So they must have produced Atmos II and III in parallel and some older SN Atmos II must have been finished late for whatever reason and it shows that the serial number is a bit less serial than I would think. Or could it be that your clock simply got a new bellow as the old one was defect in the factory even before the clock was delivered?

    Regarding the adjustment knob, looking at the clock from the front you can hardly see it, so I doubt that the symmetry is the issue here. I think that the lever with a scale makes it easier to see, control and document by how much you clock was adjusted, so it was an engineering improvement over the knob and I would think that this might be the reason to change to the lever type adjustment. But this is pure speculation on my side.
    Thanks again for your input! Much appreciated!

    rob
     
  8. MUN CHOR-WENG

    MUN CHOR-WENG Registered User

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    #8 MUN CHOR-WENG, Jun 26, 2020
    Last edited: Jun 26, 2020
    Hi Rob,

    JLC had mentioned to me in my corrrespondence with them that there is no way an Atmos can be date accurately without refering to their factory record.
    For some reason the Atmos were not produced consecutively based on serial number. They had also informed me that an Atmos with a higher serial number can be made earlier than one with a lower serial number. This can best be illustrated in a discussion from an earlier thread:

    My new 1950 Atmos Clock

    In that thread, an Atmos with serial number 56898 has a bellows dated 6-7-1953 and another Atmos with serial number 55629 has a bellows dated
    29-6-1954. So here we have a clock with a larger serial nmber that was made almost a full year earlier than one with a smaller serial number.

    Regarding the production number of Atmos II, I had written to JLC in 2004 and asked them if they have any data on this topic. They were kind enough to reply that according to their archieve record, the number of Atmos II produced from 1941 to 1949 were:

    1941 959 units
    1942 656 units
    1943 268 units
    1944 369 units ( Approximately as the June 1944 data was not available )
    1945 no record available
    1946 2654
    1947 no record available
    1948 1308
    1949 1749

    This based on the above data, quite possibly the production figures of Atmos from 1950 to 1952 that included both the Atmos II and Atmos III would be higher than the 1949 figure.

    Mun C W
     
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  9. Rob_GER

    Rob_GER Registered User

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    Hi Mun,

    your last post as well as the thread you linked are very interesting. Thanks for sharing this kind of information!

    So whatever date is generated from the serial number or bellow might be a year or two off from the actual production date. I think for the time beIng I can life for my Atmos with that , esp. as the extract from the archive is not a bargain.
    The other issue is what is the definition of production date, the assembly of an Atmos and all the regulation at the end will take some time and I would think that the date JLC provides is the date the clock was packed to leave the factory.

    On a different matter and as you are very knowledgeable, do you know how many Atmos in copper finish were produced?

    and similar question regarding the Lapis Lazuli dial, were they actual thin sclices of the rock and how many were produced?

    Thanks again for sharing your knowledge!
    Rob
     
  10. MUN CHOR-WENG

    MUN CHOR-WENG Registered User

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    Hi Rob,

    I do not have information relating to the number of Atmos made with copper colored case or those with Lapis Lazuli dial. Judging from the infrequent appearance of these on the resale market I believe not many of these were made.
    Regarding the color of the case of your Calibre 526, I checked with Lebet's book page 63, there was a Calibre 526 Model ref 5845 described as Nickeled cabinet, silvered ring dial. Rhodium case made its appearance in 1984 when the Calibre 540 was introduced.

    The production date of the Atmos referred to the date the clock was finished and having passed the quality control. In recent years the new Atmos sold was accompanied with a certificate stating when the clock was completed.
    Picture below shows one such certificate that came with the Anniversary Atmos .

    Mun C W

    20200627_210017-002.jpg
     
  11. Rob_GER

    Rob_GER Registered User

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    Hi Mun,

    thanks for the additional information.
    Rob
     
  12. new_hampster

    new_hampster Registered User

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    I believe Rob's 526 is a 5852. The photo in LOA shows 5845 has a nickeled movement, which does not match Rob's photo. The description of 5852 says 'gold-plated movement', which matches Rob's photo, and is also described as 'silvered cabinet, silvered background dial'.
     
  13. Rob_GER

    Rob_GER Registered User

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    Hi new Hamster, I think you are right, by now I found a pdf copy somewhere online of LoA and your reference matches my clock. Thanks!
    One other thing I noted looking at pictures posted here and elsewhere online it appears that some clocks have a polished finish and other like my copper coloured one and the one from Mun seem to have a brushed finish. Or are the older ones more likely to have a brushed finish an newer ones polished? I guess they have protective lacquer layer on top independent of brushed or polished.
    Rob
     
  14. Rob_GER

    Rob_GER Registered User

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    Another question I would have is regarding the Atmos dial called lapis lazuli, is this really a thin slice of lapis lazuli rock or is it blue paint with speckles on it? Maybe one of the forum members has such a clock and could let me know. Thanks a lot in advance!
    Rob
     
  15. Richb134

    Richb134 Registered User

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    I wondered the same thing. I can’t imagine it could be actual stone but they did make one with a wood dial
     
  16. etmb61

    etmb61 Registered User
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    The models section in Living on Air calls the dial Lapis or Lapis Luzuli as opposed to enamel or lacquer. In its natural form I doubt you would ever find a sample with the "regular" pattern found in the Atmos dials.
    blue_dial.jpg

    Lapis was ground to make pigments. I would suggest they probably used ground lapis with some type of binder or possibly heat fused it to make the dials.

    Just a thought.

    Eric
     
  17. KurtinSA

    KurtinSA Registered User
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    That blue dial is stunning!

    Kurt
     
  18. Rob_GER

    Rob_GER Registered User

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    Kurt indeed the blue of lapis lazuli is stunning, but the dials look like they are painted, that’s why I’m asking for members that have one and could clarify. I know that there were Atmos models where the side panels were of real lapis lazuli.
    The guy in Germany that services the Atmos has Atmos models on offer with a night blue dial, see here Atmos Kal 540 neu vollvernickelt mit nachtblauem Zifferblatt
    I think that these look great but unsure if JLC ever produced these.
    Rob
     
  19. Rob_GER

    Rob_GER Registered User

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    Is there really no one here that owns an Atmos with a lapis dial who could answer the last question?
     
  20. etmb61

    etmb61 Registered User
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    You could always contact LeCoultre directly.

    Eric
     
  21. shutterbug

    shutterbug Moderator
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    I believe the Atmos clocks are dated inside the coil housing. It's generally pretty easy to remove, and can be removed safely.
     

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