[Stoves] DIY camping TLUD with walnut shell fuel

Tue Jun 14 11:17:35 CDT 2016

Hi Neil, thanks for the recommendations. I think I'll get one of those cheap Chinese stoves to see what they can do. Most of them look the same so I assume they're all from the same factory. They're also rather squat - more power, less run time? 

The main reason I want to throttle primary air on tiny tincanium stoves is to allow some turndown for simmering. Right now, I have to boil something first on wood gas flames and then simmer on the leftover char. It would be nice to get a long flame burn time from a small can. 

I'm still amazed how so much heat can come from a tiny amount of fuel, especially compared to a campfire. Learned that the hard way, grabbing a not-quite-cooled can after a test run... 

On June 14, 2016 1:01:37 AM GMT+08:00, neiltm at uwclub.net wrote:
>On 13 Jun 2016 at 9:28, Mangolazi wrote:
>
>> Hi everyone,
>> 
>> I've been messing around with a tiny gasifier based on a peach can
>> for camping usage. I can get about 12 minutes flame time using
>> twigs, although the coals inside keep burning for a lot longer. I
>> can boil 500 ml water in 7 minutes using twigs. 
>> 
>> I recently added an outer vessel for windproofing and to preheat the
>> secondary air. Using walnut shells, I get a very hot and high flame,
>> higher than with peanut shells or twigs, with flames reaching almost
>> to the top of the pot. Total flame time goes up to 14 minutes and
>> 500 ml water boils in 6 minutes, faster than before. Please see
>> attached images. 
>> 
>> How can I prevent the flame from going up so high? 
>> 
>
>I solve this problem by varying the fuel.  Try adding thicker pieces of
>
>wood or damper wood, but mixed up with the shells, not layered. 
>Layered 
>will likely create smoke and maybe extinguish the flame.   
>
>> Is it possible and feasible to throttle primary air on such small
>> stoves? 
>> 
>
>I haven't found a way.  I tried cutting a disc of stainless steel and 
>making holes to match the ones in the base, such that I could 
>progressively turn the disc to close off the primary air, or most of
>it, 
>but I found it impossible to make the holes and retain a flat enough 
>undistorted disc after the drilling.  When placed in the bottom it
>became 
>
>clear that air would find its way around the sides of the disc not
>lying 
>sufficiently flush to the base, largely negating any blanking effect,
>so 
>I abandoned the project.  Someone with more refined tincanium fettling 
>skills than I possess may manage something though.  The idea was to
>have 
>a tab extend from the disc through a slot cut in the outer can in order
>
>to regulate the air during the burn.
>
>A simpler, but fixed for that burn possibility might be to place some 
>washers over the primary air holes at the bottom of the can to restrict
>
>the primary air, but I have not tried this since I find varying the
>fuel 
>the most satisfying solution to 'turn down'. When I'm camping it seems 
>easy to find sufficiently variable fuel to achieve the fire I want and 
>experience teaches how to do this and is very satisfying when you get
>it 
>just right.  After about 20 minutes or so, ash accumulates to the
>extent 
>that the primary air holes get increasingly blocked, and by varying the
>
>amount of riddling with a stick you can also control the primary air
>that 
>
>way.  This can be a useful way to achieve a simmer, after a rapid boil,
>
>but it is easy to lose the flame if you don't riddle.  Practice, keen 
>observation and continuous experiment teaches how to get what you want 
>from these stoves, but I still make the occasional smokey mess.
>
>Just spent five days in wet Wales doing just fine with cooking and 
>brewing on wood.
>
>Neil Taylor
>
>
>> Has anyone used peanut or walnut shells for daily cooking on a large
>> TLUD? 
>
>Not that large, unless the Reed XL counts as large?
>I've used pistachio shells successfully, and since moving a garden shed
>
>and uncovering a barrow full of mouse opened plum stones, nicely dried,
>I 
>
>have been finding these a robust, longer life fuel on their own, albeit
>
>harder to light off initially.  They sometimes get added to the mix now
>
>instead of or with damper wood when I want something less than a
>towering 
>
>inferno.
>
>Although I have made quite a few tincanium microgasifier ND TLUDs I now
>
>use the cheap chinese wood gas stoves sold on ebay for 10 UK pounds or 
>thereabouts as they are so well made and pack to less than half their 
>operating size into a small  billy can in seconds.  They are really 
>excellent - I would say optimal in design for camping use, especially 
>when finding fuel in wetter climates like the UK.  With little or no 
>moisture in the fuel the burn can be towering and last about 10
>minutes, 
>and boil a full kettle in that time, but the up side is that if the
>fuel 
>is damper, a good burn is still achievable, and more useful for most 
>cooking, and usually much less smokey.  They are also just as useful
>used 
>
>conventionally, not as a TLUD, but also easily transition from TLUD to 
>
>continuous feed to extend the burn. The char is being consumed so
>quickly 
>
>that a fresh fire is easily revived from the char stage provided it 
>hasn't all been consumed of course. With a large amount of primary air,
>
>adding fuel makes less smoke than with the cleaner emissions 1 to 6 
>primary to secondary air ratios such as the Reed fan Woodgas
>campstoves.  
>
>No reason though why you shouldn't obtain the same versatility from a 
>home made tin can stove.  Most of the ones I made aimed for the cleaner
>
>burn with the 1 to 6 ratio or thereabouts, but it made them harder to
>use 
>
>and fuel fussy.  Just put a 'grate' rather than a restricted base in
>and 
>vary the fuel, and you should find your camp stove relatively easy to
>get 
>
>and keep going.  You get soot on the pot, but that is easily wiped off,
>
>leaving a black finish that then goes in a plastic bag to keep it to 
>itself.
>
>Have fun :)
>
>Best wishes,  Neil Taylor
>
>> 
>> Thanks! 
>
>
>
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