Airwood BM Easy hike (Ukraine) fan-assisted wood stove

Discussion in 'Other Countries' started by presscall, Aug 12, 2020.

  1. presscall

    presscall United Kingdom SotM Winner SotY Winner Subscriber

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    I’m drawn to fan-assisted wood gasifier stoves like a moth to a flame.

    Sierra Zip

    Biolite CampStove

    Biolite CookStove

    Biolite CampStove MkII

    Chengdu OE-TEX

    Nomado

    The Airwood is available in three versions: the one I bought with the option of powering the fan with AA (or AAA with clever adaptor sleeves) or separate power supply; a slightly cheaper version without the external power supply option and bringing up the rear of the range one powered by batteries but without the detachable base plate the other two have - so ashes are deposited on the ground the stove rests on.

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    Detachable fan

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    Detachable base.

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    The firebox base.

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    It’s handy to have wood fuel type options and I wondered if the grid would dribble wood pellets ... but I needn’t have worried.

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    An idea of scale: left to right, Chengdu; Biolite MkI; Airwood BM Easy hike.

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    Without legs like those other stoves have, and given the heat conduction through the body and the (detachable) base having hot ash on its upper surface, it’s clear that the stove needs to sit on a stone, bare earth, or, as here a taco griddle.

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    Ready to ignite.

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    Ignition!

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    Takes a Biolite kettle.

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    The fan remains cool.

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    Kettle boiling vigorously.

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    It’s possible to overfuel a wood stove of this type and I did, the consequence being the ultra-fast boil and soot deposition on the pot.

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    One solution is ‘a little and often’ when feeding the fire.

    Another is slow burning chunks of wood. Well-dried laburnum in this case.

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    Another solution is to restrict the outlet area of the fire box.

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    I used the top plate of a scrap kerosene stove tank to make this.

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    It becomes integral to the trivet component.

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    Stoked with fuel.

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    Ignition.

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    Much more controlled burn and gasification occurring.

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    Fan remains cool of course.

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    The ‘restrictor plate’ I made packs away fine.

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    Those battery sleeves that make it possible to use AAA batteries. AA batteries install in the battery box without using the adaptor sleeves.

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    Batteries can be left installed when the external power supply is connected - there’s electrical isolation. Supply unplugged, the batteries kick in. Toggle switch at right: UP high speed; DOWN lower speed; CENTRE off.

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    My conclusions?

    It’s a good stove. Improved by fitting that restrictor plate I’d say, achieving better gassification and more complete combustion. Perfectly usable without the plate, but quicker to get through fuel.

    John
     
    Last edited: Aug 12, 2020
  2. G1gop

    G1gop United Kingdom Subscriber

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    you just Can't resist them can you John? lol
    Looks good but no legs? puts me off a bit.
     
  3. snwcmpr

    snwcmpr Subscriber

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    Another great post.
    Thank you.
     
  4. Twoberth

    Twoberth United Kingdom Subscriber

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    Great review, thank you.
    Love the restrictor plate!
     
  5. presscall

    presscall United Kingdom SotM Winner SotY Winner Subscriber

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    I did something about that and added tripod feet.

    I’ve a couple of Coleman Apex stoves and they’ve both got the accessory bolt-on feet, so this must have been a spare set I picked up sometime.

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    Easy job to drill holes in the base plate fixing struts and using the set screws in the ‘feet’ kit, bolt one to each strut.

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    Base plate can still be removed by bunching up the struts as before.

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    And because the feet fold, they don’t hinder slipping the stove into the stuff sack.

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    I set the stove on a board to check if the base is raised up enough by the feet to prevent scorching and got the stove into ‘blast furnace’ mode.

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    Not only was the wood underneath not scorched ...

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    ... I found that heat wasn’t conducted to the feet to any significant extent.

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  6. Marc

    Marc Subscriber

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    Great mod!
     
  7. G1gop

    G1gop United Kingdom Subscriber

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    Fantastic.
    You realise if I end up getting one, I'm blaming you!! Lol
     
  8. Big Si

    Big Si Subscriber

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    Really nice John.

    Si
     
  9. Big Si

    Big Si Subscriber

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    @presscall
    John, where did you get the USB plug-in variable voltage thing from mate, could you post a link please.
    Thanks.
    Si
     
  10. presscall

    presscall United Kingdom SotM Winner SotY Winner Subscriber

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    @Big Si Hi Si! In my post on the Chengdu stove (page 2) I said this about the speed controller:-
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    I enclosed it in a plastic box intended for electronic projects.

    John
     
  11. Big Si

    Big Si Subscriber

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    @presscall
    John that post must have passed me by. Thanks, I need something for another project, a portable power source for off-grid camping. She who must be obeyed needs a phone charger and I'm too Yorkshire to buy a big unit so I've made one with some batteries from work and a solar charger with a small pannel. I wanted that unit to dim some LED lights.

    Thanks
    Si
     
  12. presscall

    presscall United Kingdom SotM Winner SotY Winner Subscriber

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    @Big Si
    Try and find a UK source though. I got mine from China and it took weeks pre-Covid. Now??!!!

    John