BAT (Germany) problems

Discussion in 'Stove Forum' started by A A C, Aug 2, 2021.

  1. A A C

    A A C Norway Subscriber

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    I got a good price on an identical pair of BAT stoves. Both marked Made in Germany with no other model designation . Both looked in good condition , fairly clean no dents etc. Both have brass plated steel tank bottoms though the rest of the tank seems to be brass (non magnetic. Neither had original burners, one being a Primus and the other a Svea, both silent types . One stove had a BAT outer burner cup with the bat crest .
    I cleaned one of them up replacing seals NRV pip and pump leather.
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    Looking nice and so far so good .
    However on test firing the tank wouldn't hold pressure and an ominous pool of fuel appeared under the stove.
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    This is what I found on closer inspection ; two cracks on the tank wall . The brass looks creased . I looked at the other stove and - lo and behold * this tank was cracked as well !
    I am going to have a go at repairing one of them . I have not done so much soldering apart from attaching legs and other minor jobs ... All tips and advice are welcomed and greatly appreciated. Alastair.

    *these were not the actual words used at the time
     
  2. kerophile

    kerophile United Kingdom SotM Winner Subscriber

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    Hi @AAC you describe classic stress corrosion cracking in your pair of BAT stoves. I would advise against repair.....

    Sad tale of Phoebus No.30.

    Best Regards,
    Kerophile.
     
  3. gieorgijewski

    gieorgijewski Subscriber

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  4. A A C

    A A C Norway Subscriber

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    @kerophile @gieorgijewski
    Thanks gentlemen . Very sound advice . I now realise the cracks appeared when I pressurised the tank to a working pressure . I had done a low pressure leak test with a balloon over the riser when I was cleaning the tank . It held pressure then . Looking at this from a «glass half-full» perspective, I now have lots of extra parts !
    Do you think the steel bottom on the otherwise brass tank has been a factor ?
     
  5. gieorgijewski

    gieorgijewski Subscriber

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    in my case - finger dropped down inside the tank...
    bottom brass - is only foil...
    ballon test is not good - not enough high pressure

    pressurised tank under water test - will be better
     
  6. ulysses

    ulysses Subscriber

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    The "silver lining" / good news is that you have two, high quality Swedish burners. Keeping searching; there are good quality No. 1 and 5 fonts / tanks out there without burners, to be had cheaply, most likely.

    Paul
     
  7. A A C

    A A C Norway Subscriber

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    I am an experience richer after the disappointment . I have learned about classic stress cracks ! I have two Swedish burners, tank lids, pump pistons and two very solid looking NRVs with hex ends .
    These stoves are now officially out of circulation. A fitting resting place for worn out BATs - hanging upside down in the attic ! ;)
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