Results 1 to 16 of 16

Thread: Circled T

  1. #1
    Member
    Join Date
    Jul 2014
    Location
    CZ
    Posts
    75

    Default Circled T

    Does anyone know when the War Office/MOD first started to use the Circled T to indicate the Tritium dialled watches? It's probably in Konrad Kirim's book but I am 600kms away from my copy, and I can't find anything on the world wide web!

  2. #2
    Super Moderator dave's Avatar
    Join Date
    Jul 2008
    Location
    Blighty
    Posts
    7,031

    Default

    I have always *assumed* the early to mid 60s but supporting documented info would be nice..

  3. #3
    Member
    Join Date
    Jul 2014
    Location
    CZ
    Posts
    75

    Default

    Its on the Mk XI's and the Omega 53's.. but I guess they are redials.. as I have obviously seen the IWC without the T and I have seen 53 thin Arrow's with and without the T as well.

  4. #4
    Senior Member
    Join Date
    May 2010
    Location
    London
    Posts
    1,551

    Default

    1955 Lemania asymmetrical chrono?

  5. #5
    Super Moderator dave's Avatar
    Join Date
    Jul 2008
    Location
    Blighty
    Posts
    7,031

    Default

    wasn't the first series 3 issued in 1956? but I take your point -

    however none of the 6B/159 1956 Dennisons were marked as such.

  6. #6
    Super Moderator dave's Avatar
    Join Date
    Jul 2008
    Location
    Blighty
    Posts
    7,031

    Default

    I guess that we now really need to go back to the MoD Def Stans..

  7. #7
    Senior Member
    Join Date
    May 2010
    Location
    London
    Posts
    1,551

    Default

    Maybe it was '56. That's the earliest I've ever handled, but I seem to recall someone telling me that there were some from '55.

  8. #8
    Member
    Join Date
    Jul 2014
    Location
    CZ
    Posts
    75

    Default

    Quote Originally Posted by rodabod View Post
    Maybe it was '56. That's the earliest I've ever handled, but I seem to recall someone telling me that there were some from '55.
    But Dave has a point, the Omega/Jaeger 6B/159 56 re-case watches do not have the T.. so that would suggest that whenever the MOD decided to bin Radium and use Tritium then watches such as the Lemania Chronographs, the Mk XI's, the Omega 53's and one or two others had the dial re-done... this doesn't include the 6B/159 re-case's so either they didn't retain them or couldn't be bothered re-dialing them yet again! and I don't believe the second scenario.

  9. #9
    Member
    Join Date
    Nov 2014
    Location
    Sweden
    Posts
    309

    Default

    Quote Originally Posted by dave View Post
    wasn't the first series 3 issued in 1956? but I take your point -

    however none of the 6B/159 1956 Dennisons were marked as such.
    But were/are the 6B/159 1956 Dennisons Tritium?

  10. #10
    Super Moderator dave's Avatar
    Join Date
    Jul 2008
    Location
    Blighty
    Posts
    7,031

    Default

    Quote Originally Posted by drk View Post
    But were/are the 6B/159 1956 Dennisons Tritium?
    yes I think that we can assume that the original applied lume on these was tritium.


    can anyone check to see if the circled T is mentioned in DEF-3-A please?

  11. #11

    Default

    DEF-3, 3A & 3B and Def Stan 66-4(Part 1) Issue 1 Watches, Wrist, Divers dated 30 Aug 1968 all state:

    'The brightness of the luminous markings of the dial, hands (and elapsed time bezel - divers only) is to be in accordance with
    the latest issue of the Ministry of Technology (Aviation Group) Design Note No. 2 and the materials as defined therein'.

    Circle T is first mentioned in DEF STAN's for the following.

    Watches, Chronograph, Wrist - Issue 1 dated 11 April 1969
    Watch, Wrist, General Service - Issue 1 dated 9 July 1969
    Watch, Wrist, Navigators - Issue 1 dated 10 July 1969
    Watches, Wrist, Divers - Issue 2 dated 1 January 1971


    Terry

  12. #12

    Default

    I believe radium was 'banned' in/from 1956, so it quite likely tritium was applied from 1955. To think that huge number of affected instruments were simply buried 'somewhere in England'.

    Some Smiths Empire luminous pocket-watches have a luminous rating (3, 5 etc) - likely to international standards, but are such ratings defined anywhere; I've not found anything yet.

    ... which reminds me, where have all our glow-worms gone?

  13. #13
    Member
    Join Date
    Jul 2014
    Location
    CZ
    Posts
    75

    Default

    Having just looked online I found this....

    http://www.vintagewatchstraps.com/luminous.php

    and about half way down is an excerpt from 'Air Publication 112G-0815-1 July 1966' which can also be found here...

    http://www.mwrforum.net/forums/showt...-113-Questions

  14. #14
    Super Moderator dave's Avatar
    Join Date
    Jul 2008
    Location
    Blighty
    Posts
    7,031

  15. #15

    Default

    Interesting time line, but very US orientated; l am sure British Boffins would have had the capacity to make tritium, if not in commercial volumes. So, when was radium declared iffy?

    Re 1956, I am sure I was told that year when researching Kelvin & Hughes (Smith's post-war aircraft insturments business).. but everyone's memories plays tricks and we're only human (allegedly)!

  16. #16

    Default

    Finally dug out the 1954 Smiths catalogue: Empire pocket watches 30 grade; Everest wristwatches 80 grade. I presume these are 30 ug and 80 ug (radium elements per gram) - can anyone confirm?

    There were several radio-luminescent materials used in paints for optical instruments, rangefinders, compasses, watches among which were thorium compounds... how can we tell?!

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •