Hi All, I have a post on; A spill-free alcohol bottle. It, by all accounts, was a bit of a lead balloon fizzer. However, there was a more positive interest in the tiny alcohol burners that I mentioned in the same article. It was meant to give some context as to why I would be faffing about over spilling or wasting a few grams of alcohol. Maybe it should have been for the folks on the ultralight backpacking part of the forum. But they are nit-pickers (like me).
Neon particularly wished to know more or all the details about the little burner. So, honouring my promise, here they are, but the burner is so simple, like me, that there is not much more to tell.
Background. For many years, where possible, I use a gas stove that uses wood to make gas. I use that gas for heating, cooking and snow melting. I sparingly use alcohol as a backup fuel in the wood gas stove if:
There are no stick or remotely combustible organic matter,
Wood burning is not allowed or,
I just need to pack up camp quickly before bad weather hits (A bit like a Dingos breakfast; ‘A quick pissss and a bit of a sniff around. In my case, I include a hot caffeine hit in the routine.
It makes sense to me to use alcohol as this backup fuel as it can be carried in the right quantity without waste according to a trip’s requirements.
Pure alcohol also has many other wonderful uses, for bushwalkers, that other fuels don’t have. Furthermore, it also makes sense for the burner to be tiny and weigh as little as 3-5g so that it is an inconsequential addition to a backpacking load. This is particularly nice when luck may mean that it never gets used on a long trip.
I tried my old faithful and now redundant Trangia burner. As for poor Goldilocks, it was just too:
Heavy and big to fit in my wood gas stove kit,
Inefficient because the flame was too big, and
Hot so that there was too much heat feedback from the pot
Here is a photo of the Trangia burner in my smallest titanium roll-up wood gas burning stove. It was taken before the excessive heat feedback effect sent it out of control.
I say that I discovered the bottle top burner after 50 years of searching, but I should give Patric’s bushcraft thanks and credit for the idea from the YouTube video below.
The build. Start with some screw-caps from whisky bottles (or wine for the culture vultures). Remove the sealing disk. Roll the thread shapes flat with a hard metal rod or tube, rolling against a hard surface. That makes a fully functional minimalist burner. Another option is to add some rock-wool to the cavity as an anti-spill measure. I think it makes the lighting up easier. It acts a bit like a wick. These two burners are fully functional, but I could see from both the yellow colour flame and the black colour of the pot bottom things were not ideal. As a life-long innovator, pyromaniac and wood gas combustion/stove geek, I could see the potential for large improvement in something so small. I could achieve it without offending that Ultralight Lot.
I added a short slotted chimney (or flame guide) that would:
Protect the flame from wind,
Increase flame draft,
Create flame turbulence, and
Force the flame to spread over the bottom of the pot.
To make the flame guide more packworthy, I made it so that it could telescopically pack down. This also allowed it to be finely adjusted up to the optimum spacing from the pot bottom to get that blue flat mushroom flame.
The flame guide is made from 0.1mm thick stainless steel or titanium foil. I roll the foil with a 10mm pipe against a firm foam rubber mat until it becomes a cylinder with a small overlap. I weld the overlap to make the rigid flame guide tube and weld on two little saddle things to slip the mounting legs into. Similarly, I make another slim ring to go around the lid and weld the mounting legs to it. The legs insert into the saddles and the flame guide can be slipped down while backpacking and lifted up to within about 5mm of the pot to get that lovely hot blue mushroom flame as shown in the video. The red tip of the top of the guide is reaching 500C. You could make one out of aluminium foil from a coffee can without the welding, as I used to. But then it would not be quite as cool and it would be close to its melting point.
Here is a video of the alcohol flames with the flame guide, Then the sooty carbon yellow flame without the guide:
Here is an ode to alcohol:
For an ultralight stove, alcohol’s a choice gentle fuel, A whisky bottle lid maketh a sweet burning tool, Whisky burning’s expensive and non-wowsers offensive, Moonshine’s the fuel. The cook can nick a spare Joule.
Now Noeon, if you are equally perplexed about my wood-fuelled gas stoves, here is a little video of a little double pot roll up titanium stove.