Primus 34 - 1927.

Discussion in 'Primus No:34' started by Robert Radcliffe, May 26, 2020.

  1. Robert Radcliffe

    Robert Radcliffe United Kingdom Subscriber

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    A follower of my #stoveaday postings on Instagram contacted me a couple of weeks ago with the offer of a Primus stove. Thinking it would be another 96, 210 or 5 I nonetheless said I was interested and asked for details. 'I think it's a rare one' he said. Still cautious as every Primus these days seems to be rare on certain auction sites I asked him to send pictures.
    I was delighted to receive pictures of this lovely little 34 dating from 1927. At first a reluctant burner despite my friend fitting a new jet. I swapped out his jet with my preferred choice of jet from Base-camp, changed the fibre washers and cleaned every hole in the silent burner. I estimate a quarter of them were blocked to some degree or other. An old bent cleaning needle rod from a Coleman generator was the perfect size. We never throw anything do we? A much better burn resulted. So my Primus 34 is today stove 64 on my #stoveaday feature since my lockdown started.

    20200525_155439.jpg 20200525_154035.jpg 20200526_082318.jpg 20200526_082335.jpg 20200526_082409.jpg 20200526_082537.jpg 20200526_082635.jpg 20200526_082643.jpg 20200526_083920.jpg
     
  2. ROBBO55

    ROBBO55 Subscriber

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    Very nice! :thumbup:
     
  3. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi @Robert Radcliffe A nice stove and great photo presentation.
    I have a Primus No.4, from 1926, which shares the same burner type to yours, it has the very deep shirt around the vaporisation chamber.

    Primus No.4 - 1926

    Please can you tell me whether your stove is fitted with a jet with 0.23mm aperture or 0.32mm aperture?

    Best Regards,
    Kerophile.
     
  4. Robert Radcliffe

    Robert Radcliffe United Kingdom Subscriber

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    @kerophile the jet fitted is 0.32mm as the one fitted (which was smaller) simply wouldn't produce a clean burn. I'd be interested to know if it originally had a 0.23mm jet.
     
  5. z1ulike

    z1ulike United States SotM Winner Subscriber

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    Great stove. I've never seen that model before. You've got it running nicely, well done.

    Ben
     
  6. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi @Robert Radcliffe . I believe that the small silent burner used on Pr.4 and Pr.34 stoves was designed to use a jet with a 0.23mm diameter aperture.


    The 1930s Primus burner overview in the Reference Library gives the jet number for a No.4 burner (#4125) as #4391, which I believe has a 0.23mm diameter aperture.

    The jet for the roarer burner for a No.210 stove and a No.1 stove is given as #4390, which I believe has a 0.32mm diameter aperture.

    Best Regards,
    Kerophile.
     
  7. Robert Radcliffe

    Robert Radcliffe United Kingdom Subscriber

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    Thanks @kerophile that's interesting and means I'm going to try other jets out. I'm reluctant to try decarbing the burner as I blew the tubing on one recently doing a heat quench cycle.
     
  8. Lennart F Sweden

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    Looking around, I only found a row of indications that Primus 0 and 4 types of burners should have a smaller jet than the average 0,32mm. 1223594571-4605_02.JPG
     
  9. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi, I find that I tie my brain in knots when trying to understand jet aperture sizing over time, with several competing manufacturers.
    This is one of the most useful tables I have seen so far:

    upload_2020-5-26_17-46-30.jpeg

     
  10. Lennart F Sweden

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    Yes, that list tells that Primus 4 has its very own jet and the size should be something between 0.25 and 0.30mm to make any sense.
    Munstycken Fogas.jpg
     
  11. The Warrior

    The Warrior United States Subscriber

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    Sweet stove man, congrats.