Optimus 300 J-tube replacement

Discussion in 'Fettling Forum' started by Kuman, Nov 16, 2020.

  1. Kuman Sweden

    Offline
    Joined:
    Sep 4, 2020
    Messages:
    2
    Location:
    Sweden
    Greetings from Sweden!

    This is my first post so: hello Everyone!

    I've just got (for free almost) Optimus 300 lamp, simillar to the one Nils has here: 1931 Optimus 300

    I tried disassembling it before lightning. Unfortunately J-tube broke while trying to unscrew holding nut and mantle holder.
    I've managed to free these parts (holder and nut) from tube rests but now the tube is shorter by a good 12mm.

    I'm considering turning a brass extension/adapter to fill this miss but I'd rather replace the J-tube instead.

    Do you happen to know if any other lamp uses same size tube? I recall someone mentioned that it's a copy of Petromax (?) lamp but which model?

    Tried finding replacement in Fogas but they don't seem to have it.

    In the worst case the lamp will serve as a donor for the other 300 but it would feel good to resurect her.


    IMG_1292.JPG IMG_1291.JPG IMG_1290.JPG IMG_1289.JPG
    IMG_1288.JPG
     
  2. podbros

    podbros United Kingdom Subscriber

    Offline
    Joined:
    Dec 27, 2015
    Messages:
    1,394
    Location:
    Wirral
    Hello @Kuman .. Welcome to CPL!

    Thank you for showing your lantern, hopefully someone on here will be able to help you ?

    Good luck with everything :thumbup:
     
  3. Nils Stephenson

    Nils Stephenson Founder Member

    Offline
    Joined:
    Sep 9, 2010
    Messages:
    2,634
    Location:
    Copenhagen, Denmark
    Unfortunately I havn't found a replacement for these older J tubes. If you have the skills, then the best option is to try and extend the original one. This is something I have thought about before, but don't have the skills to do it. Just make sure you don't decrease the inner diameter.
     
  4. Graham P

    Graham P Australia Subscriber

    Offline
    Joined:
    Mar 3, 2012
    Messages:
    881
    Location:
    Albury area NSW AUstralia
  5. Kuman Sweden

    Offline
    Joined:
    Sep 4, 2020
    Messages:
    2
    Location:
    Sweden
    Thank you gentlemen!

    I think I'll then try brazing my adapter, since it's only few mm which are missing.
    I'll post pictures once I'm done.
     
  6. MYN

    Offline
    Joined:
    Feb 28, 2018
    Messages:
    1,682
    Location:
    Malaysia
    Yes, you could try to fit on an adaptor piece. Threaded or brazed.
    Quite a lot skills and work would be required for jointing the tube without reducing the inner diameter.
    I'd definitely give it a shot.
    Brazing on a thin connecting sleeve, grinding off the excess, re-threading and some touch ups in the bore, etc. Finishing off so that it'll look as if it had never been broken. Easier said than done.
     
  7. BigStevie

    BigStevie United Kingdom Subscriber

    Offline
    Joined:
    Dec 5, 2018
    Messages:
    1,538
    Location:
    Scottish Highlands
    @Kuman

    Hi and welcome to the forum. Good luck with fettling your lamp!
     

Share This Page