Hasag 351L in steel re-visited.

Discussion in 'Fettling Forum' started by Henry Plews, Jan 21, 2019.

  1. Henry Plews

    Henry Plews Subscriber

    Offline
    Joined:
    Jun 23, 2014
    Messages:
    660
    Location:
    North Yorkshire
    I got this lantern from @MarkC. (See here for more images of original condition Hasag 351L in steel )

    IMG-20180304-WA0002.jpg

    In spite of its looks, the overall condition was quite good and I was pleased to find that the inside of the steel tank was free of rust and looked quite clean, never the less, it was washed out with cleaner / degreaser.
    The tank was cleaned back to bright metal in the sandblaster and sprayed with etch primer, it would later receive a coat of PlastiKote Garden Green.
    The support collar was cleaned with fine wire wool, polished with Autosol and finished with High Temperature clear lacquer.
    The frame and inner hood were sandblasted and painted with VHT silver paint which was baked on at 200 degrees C for 30 minutes.
    All other steel parts were cleaned with a wire wheel in my Dremel.
    The filler cap got a new seal, the needle control got new graphite packing, a new Petromax 250cp nozzle replaced the broken original one and a repro Hasag glass (122mm x 122mm) was ordered from Hytta.de

    The vapouriser was a different story, it was a little bent but the real problem was that the threads at the top end and also on the jet, were destroyed. I believe they were originally M6 X 1.0 as found on two post war
    in my collection – could this be a clue as to the lanterns age ?


    After cutting off the upstand above the heatsink, Stu @loco7lamp machined and silver soldered in place, a new upstand which was threaded M5 x 0.9 to match one of my spare Hasag jets. Notice how concave the jet is.
    IMG_1979A.JPG

    With everything re-assembled, a dunk test proved there were no leaks and a test burn gave a nice clean flame. So with a 500cp Peerless mantle fitted it was time for lighting. Hasmar A01A.JPG

    Very bright but I had to use the cleaning needle every 15 or 20 minutes and I began to wonder if the tank and vapouriser were as clean as I thought they were, so I emptied the tank and rinsed with fresh kero. One and a half tankfuls of clean kero later and still having to use the needle every 20 minutes or so, I decided something must be done. The air gap is fixed but I still had a couple of options, I could have raised the mixing tube by fitting a washer underneath this flange

    IMG_1982.JPG

    But after comparing with other Hasag jets,
    IMG_1983.JPG

    I decided to shorten the new jet by reducing the concave.
    Hasmar A04.JPG Hasmar A05.JPG

    Would 1mm make much difference ? I like to think that it does, since shortening the jet, I burned a full (1ltr.) tank and only had to use the needle twice. It may be just that the lantern has finally settled down, Ether way, I'm happy with it.

    Henry.
    .
     
  2. george

    george United States Subscriber

    Offline
    Joined:
    Nov 8, 2011
    Messages:
    438
    Location:
    USA
    GREAT job, Henry!:D/ Real winner, it's rare any of mine turn out that good!:thumbup:
     
  3. Tony Press

    Tony Press Antarctica Subscriber

    Offline
    Joined:
    Aug 28, 2012
    Messages:
    3,759
    Location:
    Stinkpot Bay, Howden, Tasmania, Australia
    Very nice work, Henry (and Stu).

    Cheers

    Tony
     
  4. Henry Plews

    Henry Plews Subscriber

    Offline
    Joined:
    Jun 23, 2014
    Messages:
    660
    Location:
    North Yorkshire
    Thanks George. I've just remembered that it wasn't just the vapouriser (generator) that was a problem, I forgot to mention the NRV in the pump tube which was stuck fast but had to be removed because it was leaking pressure. Long story short, I eventually had to unsolder the pump tube from the tank and even with heat and quench the NRV still refused to move so I drilled it out. Unfortunately, the drill veered to one side and destroyed the threads. Again, Stu @loco7lamp came to my rescue by cutting off the end of the tube and soldering on a new end piece drilled and tapped to take a readily available Petromax NRV after which, I soldered it back into the tank using the mark of the original solder as a guide to correct positioning.
    The rest of the fettle was basically cosmetic.

    Henry.
     
  5. JEFF JOHNSON

    JEFF JOHNSON United Kingdom Subscriber

    Offline
    Joined:
    Nov 28, 2010
    Messages:
    7,434
    Location:
    Shetland Islands UK..
    Well fettled Henry and Stu!:thumbup::thumbup:
     
  6. Henry Plews

    Henry Plews Subscriber

    Offline
    Joined:
    Jun 23, 2014
    Messages:
    660
    Location:
    North Yorkshire
    Thanks Jeff.

    Henry.
     
  7. James K

    James K Subscriber

    Offline
    Joined:
    Nov 10, 2017
    Messages:
    52
    Good work Henry, it's running well.
    That NRV sounds like it was a lot of work, you had to earn this one.
    James
     
  8. Henry Plews

    Henry Plews Subscriber

    Offline
    Joined:
    Jun 23, 2014
    Messages:
    660
    Location:
    North Yorkshire
    Thanks James. It wasn't the first time I've had to remove a pump tube and solder it back into the tank after fixing the NRV but this one was unbelievably obstinate. I dare say that I could have
    repaired it myself but I didn't have the correct size tap so it went with the vapouriser to Stu.

    Henry.
     

Share This Page