Sunday, April 5, 2009

Bushwacker Wood Stove

The Bushwacker is a compact wood burning backpacking stove. It was designed by J. Falk and is a cost effective alternative to the Bushbuddy (though it actually functions quite a bit differently). It's not made from such high end stainless steel - but it costs approx. $85.00 less. Sure, it won't last quite as long, and maybe it doesn't look as cool, but it also won't hurt your budget nearly as much either, costing you under $30.00.

Or... you could make your own, using the same materials that the Bushwacker is made from for around $5.00. You can buy the DIY instructions from Jim here. If building your own stove sounds a bit daunting, I recommend buying one from J. Falk. He's a great guy and has put a lot of work into perfecting the design, and supporting cottage industry is certainly the best way to go.

This was my DIY attempt without directions, so it's not exactly how Jim builds his (and I have a feeling his works better). This one worked fairly well though. What I like best about it is that it's a "light it and leave it" stove. You pack it in with wood, get it going properly, and then you don't have to add any more wood. You can also adjust how fast and hot it burns by opening or closing the air inlet holes at the bottom of the stove. All in all, a great piece of work, and very cleverly designed.

Materials I used:
- quart sized paint can, preferably unused (Home Depot - $3.99)
- 27 / 28 oz vegetable can (Grocery Store)
- hardware cloth for pot stand and fire grate
- some kind of wind screen (Aluminum Flashing is ideal)
- something to poke holes in metal (a step-bit or hand punch work best)


Here's how it looks all set up.


The outer wall can be turned to close off the air vents to suit.
The outer wall and inner wall cans are not permanently connected.

Here are the two cans side by side. When you line up the seams in the cans the lower holes match. Air is introduced both into the bottom of the wood pile as well as the top holes where it mixes with the wood gas and ignites.

Top view of all the parts. The Hardware cloth inside the
smaller can is used as a fire grate and is removable.


Side view with a small stainless steel bowl as the cook pot.
The air inlets are closed half way in this shot.

A good windscreen is necessary in order for the stove to go into gas mode. J. Falk uses a tinfoil windscreen. He's a better man than I, it's just so lightweight that I couldn't keep it from pushing against the stove when there was even a little wind. Aluminum flashing worked very well. In this shot the windscreen is a bit wider than it should be while in use - keep a 1" gap all the way around.

Here's one of J. Falk's videos from Youtube on how to operate this stove.

9 comments:

  1. Thanks for the plug on my Bushwhacker stove. The stove you made is almost dead on to my design, you're missing the secondary air intake holes in the outer can, which makes the stove work much better.

    Glad you liked it.

    J. Falk
    www.TrailGear.org

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  2. Thanks Jim - you've come up with a pretty ingenious design. I was not convinced it would work, with only those four holes in the bottom. I was pleasantly surprised. And I love the integration with an alcohol stove yours has. It's such a good idea to have a light backup alcohol stove with a wood burner.

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  3. Hi. Thanks for your insightful posting. I was inspired by your trial and managed to make a stove looks very much like J.Falk’s without his instruction. But somehow it does not work that great. The problem I think is the size of the internal can. I picked a 28oz tomato can that fits inside of the paint can very snugly. But since it fits so well inside of the paint can, there is almost no space between the two cans, maybe 1/16” or 1/8” at most. This doesn’t seem enough space for the secondary air to go up between the cans and exit from the top holes of the internal can. I have been looking hard on the photos of your stove and J. Falk’s and I can’t tell any difference from mine. Can you tell me exactly what kind of can you used and how much space you have between the walls of the two cans? With my present design, I just can’t see any benefit of two-can design over one-can design. I will appreciate your input.

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  4. Bushpuppy -
    I used a can that held peaches for my inner liner. I'm guessing it's the same size as the one you used. There isn't a lot of room between the cans.
    The major thing that I got wrong in my initial build is that I did not notice that J. Falk has (8) 1/8" holes drilled around the outer can, a little below where the inner can top holes are. This allows much more air to get in.
    I do think the two wall stove is superior to the single wall design. I have had more luck with the Bushbuddy clone that I made just because it allows so much more air intake. That makes it just a little less finiky.
    That said, J. Falk's design is fantastic and once you get it built just right and are comfortable with lighting it off correctly - it does a really good job.
    I think he sells the directions for $5.00 or so, and uses the income to support diabetes research - that's not very much $$ to spend, it's for a good cause, and you get very very thorough build and usage instructions.

    Oh - and the real key to any of these stoves is this: very very very very dry twigs.

    Good luck. Don't burn anything down. :)

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  5. Thanks a lot for your tips. I read J.Falk’s comment above so I did make those little holes on the outer can. What I am disappointed with my stove is that there is no flame coming out from the upper holes of the internal can. So your stove makes that nice circle of flame out from the upper holes?

    Also mine had quite a lot of smoke came out before the fire got going. But I guess that has more to do with my fire starting skill and not-so-dry twigs as you mentioned.

    Didn’t know J. Flak’s instruction was only $5 or so. That will be more cost effective than trying to figure it all out by myself since that will save a lot of wasted cans. Also it's good to know that my money may be used for a good cause.

    I just started making my version of Bushbuddy DIY clone today. That’s encouraging to know that Bushbuddy design will be easier to make it work.

    Do you know if the twigs in Bushbuddy can be burned top down like Bushwacker and Bushwacker can burn bottom up like Bushbuddy? I don’t see much difference in their working principle between these two designs. I hope you don’t mind my ignorant questions.

    Luckily I haven’t burned down anything yet. But sure this stove making thing is getting addictive.

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  6. Sorry for the delay in responding.

    I get a lot of smoke as well. Probably for the same reasons you mentioned - lack of practice and not always the absolute driest twigs.

    The Bushbuddy close is used the same way as the Bushwhacker - it just doesn't have the flame regulation feature (by way of adjusting air intake) that the Bushwhacker has. For me, that's not an issue.

    Plus, I actually do like the ability (and sometimes necessity) of adding extra fuel.

    Stack your twigs in rows, cris-crossing each row, so they are pretty densely packed and come to just below the top air holes. Add some tinder (petroleum jelly saturated cotton balls are fantastic - only need a small portion of one). Then finish it off on top with some very thin twigs that will light easily. Fire it off with a sparker and wala! You should be in business.

    Oh, here's a hint - it takes a good while for the fire to get going properly. Don't get impatient like me and fiddle with it... that's where most of the smoke comes from.

    I'd love to see how your Bushbuddy clone comes out.

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  7. Thank you very much for your detailed description of your fire starting technique. Petroleum jelly saturated cotton ball sounds like a good idea and very creative. While I was hiking in Northern India I saw mountain villagers used little wood sticks or twigs (about 2 or 3 inch long) rolled in pine tree sap as tinder. They were using matches and not sure if this method work with sparkers. Ever since whenever I see big sap coming out from tree barks on trail I collect them just in case.

    I agree with you about the Bushbuddy’s advantage with ability of adding extra fuel. That’s one of the reason I want to make Bushbuddy clone. When my version of Bushbuddy clone is done I will post it on somewhere on the web and I will certainly let you know.

    Have a happy holiday!

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  8. I love the big stove specially because i like to cook all kind of recipe, how ever i prefer to have a reasonable place. Actually i saw a beautiful stove in a house that was published in costa rica homes for sale it was big and beautiful, i think i will go there because it catched my attention.

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  9. Love this stove ..Was able to boil water in about 8min in the rain and was able to cook lasted about 32 min ....Thanks

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