This post is about adding an optional micro oil burner to a miniature wood burning tent stove for backpacking winter camping. The ultimate aim would be to make the stove into an ‘all-night’ tent heater that uses only a small amount of vegetable oil for the task.
Note: Post page still under construction.
Introduction
Oil is one of the most energy-dense substances that mere mortals like us can carry in a backpack. For an edible vegetable oils such as olive oil it can be both a food-fuel for trekkers bodies and a combustible fuel to burn to keep them warm.
I have posted on an Experimental barrel-stoves from coffee tins. Searching for the ‘holy grail’ of an ‘overnight’ ultralight tent stove warmer. I have examined the possibility of making a tiny stick burning tent stove burn all night with wood sticks as fuel. While the experiments led to some innovative stove designs, I conclude that even a two-hour burn without refuelling would not easily be achieved.
I made a subsequent post Can a tiny wood-fired tent stove be fired with oil? In it, I described some history of primitive oil-burning to provide heat for blubber rendering, snow melting, cooking and warmth.
I also describe some of my own micro oil burner tests that could lead to a long-burning ‘all-night’ fuel supplement for a tiny wood burning tent stoves for winter backpacking adventurers in remote areas.
My Simple Dome Stove uses wood sticks to provide an intensely hot burning stove. It is very suitable for providing; recovery warmth from winter adventure, snow melting, hot drinks for hydration and cooking. Then when that is over, My vision was, to be able to turn the wood stove into a gentle oil burner. Hopefully, this burner could run all night to keep the cold and icicles away.
A simple ‘dribbling wooden wick oil feeder‘ within the Simple Dome Stove showed its potential to sustain a hot flame (and stove surface heat) with an oil feed rate of ~1.5g/minute. This meant that it could run for 8h on 720g of oil.
The oil-soaked wooden wick worked well. However, it did slowly burn away and would not be a sustainable wick for an ‘all-night’ tent warming stove.
The challenge that I address in this post is to see if I can develop non-combustible alternative wick? Such a wick, for example, could be a metal frame with a fibrous ceramic coating, that could disperse, heat and gasify and pyrolyse the oil to support a clean and stable flame.
The furry tongue oil feeder
The oil feed was made of a rectangle of stainless steel foil with a stainless steel oil feed groove welded to it. It was covered with fine stainless steel mesh. Between the foil and the mesh, I stuffed in some fibreglass cord to make the heat resistant oil wicking surface. Finally, the whole unit was curved so that it could fit in through the fuel/air port opening.
The good news. The oil feeder fitted into the simple dome stove fuel port nicely and ignited well with the use of a little wood and charcoal and waxie fire starters.
It continued to burn without any need for adjustments or supplementary fuel feeding as would be required for an all-night tent heater. The stove temperature was much lower than when burning wood sticks but still would provide significant warmth in a small tent.
The bad news (the lessons). The oil combustion was not clean enough and soot accumulated in the flue pipe. It eventually fell down the flue pipe and largely blocked the portion of the fire dome (behind the flame guide) that would otherwise allow the exhaust to flow freely to the flue pipe.
It was fun to simply run the stove on wood sticks and see the heat of the fire burn up all the soot albeit with a little more smoke. Satisfyingly, it left the stove ‘clean’ once more. “I end-for-ended the flue pipe and it cleaned up quite nicely too.”
Discussion & conclusion
My oil feeder worked and was a very light and compact supplement for a tiny wood burning tent stove. However, the combustion was not clean enough to be a sustainable way to fuel an all-night tiny tent stove.
If oil is to be used as a supplementary fuel for an all-night stove, the burner will need to be able to maintain its own higher temperature to make the oil vaporize better and combust more completely. A burner made of highly conductive copper foil might help to transfer heat to the oil for this purpose.
Another possibility may be to use an oil or wax that has a lower vapour temperature that may naturally burn cleaner. According to Redhill General Store olive oil is very clean burning lamp oil. So maybe I should give that a try on my oil feeder before ‘giving up’. It would also be consistent with my dietary choices if I needed to drink or cook pancakes with my fuel.
A very much smaller (scaled down) version of Gerry’s tin can oil burner may work.
Tim
I have another post about storing the heat from a powerful tent stove in a 33g soft bottle to keep you warm in your sleeping bag all night. A good substitute for keeping the stove burning all night.
