Fundamentals of The Portable Grease Stove

For some of the wanderers, the first fundamental of the portable grease stove is not unrelated to that prophesy of the Book of Revelations: "Babylon the great is fallen, is fallen, and is become the habitation of devils, and the hold of every foul spirit, and a cage of every unclean and hateful bird."  And more to the point, at the end of said chapter 18: "And in her was found the blood of prophets, and of saints, and of all that were slain upon the earth."

Besides avoiding the distractions of commerce or servitude to unworthy masters, as the disciples of all the great wanderers do, many of the wanderers recognize the unclean city perfectly fulfilled in SPU, in which was found the blood of all that were slain.  This vow of poverty, this wandering is not a lighthearted thing, but a solemn attempt to avoid any share of responsibility for spilling the blood of the just.  Or of the unjust, for that matter.  To a certain extent this fundamental realization impels the wanderers to avoid the acquisition of SPU-produced goods, particularly with SPU-controlled money, and to rely instead on what can be gathered from the earth without provoking the possessive defenses of the unenlightened, and without any thievery or fraud. To emulate the sparrows, as it were.  In a word, to scavenge.

The second fundamental is more mundane: cooked food is good for you, particularly when wandering in populated areas of industrial or post-industrial societies, when the food bag holds items that cannot safely be eaten raw or easily cleaned, or when warm food or tea is needed to fend off the cold.  Some means of cooking is essential to the wanderers enduring over the long haul.  Cooking over an open fire often does not fit the bill, solar stoves are bulky and mostly useless, and gasoline, kerosene or propane stoves, while quite useful, require the handling of noxious fluids or heavy bottles; and worse, the regular use of money.   A cooking means should if possible be fashioned from scavaged flotsam, not purchased in a store, and must be compact and lightweight.  It should consume a fuel that is energy dense, relatively clean and safe to  handle, and most importantly readily obtainable everywhere without the use of money.  It should burn hot enough to cook a healthy mess of stew in a reasonable period of time, without burning too brightly and attracting unwanted attention, and preferably without leaving a lot of soot on the pot.  It might seem impossible that such a fantastic device could exist.  For a long time, it didn't.  And then a wanderer invented a portable grease stove, which looked a little like this:

Partial Breakaway View of a Grease Stove (Not To Scale, Pressurized Air Supply Omitted)

The body of the stove can be constructed from an empty soup can.  For portability, a largish can about four inches in diameter and six inches high works well; the exact dimensions are unimportant.  A hole to match an available scrap metal tube about one-quarter to three-eighths inch in diameter is made in the side of the can about one-third of the way up from the bottom, using the awl of a "Swiss army" knife or similar tool.  A strip of cardboard is cut about as long as the inner circumference of the can and narrow enough to fit comfortably below the hole made in its side.  A cotton rag, such as from an old T-shirt, is wrapped around the strip and the assembled rag-strip is curled to a circular shape and inserted to rest inside the can below the hole.  A grill for supporting the pot is fashioned from any available metal; if not available, a few blocks or rocks can be arranged around the can to support a pot.  The stove can be charged with about a half cup of old fryer grease scavenged from behind any donut shop or fast food joint, and it then is almost ready for use.

The rag-strip can be lit and will function as the wick of a rather large candle.  It is entirely unsuitable for cooking, as such, even if numerous ventilation holes are made in the side of the can.  With air holes, the wick will remain lit, but will not burn hot and will produce too much soot.  To render it useful, a gentle, steady stream of air must be blown through a tube inserted through the hole in the side of the can.  A little experimentation with the rate of flow will transform the smoky, sooty combustion in the can into a much hotter, bluish, nearly smokeless fire.  If the grease was obtained from a donut shack, it will smell faintly of vanilla.  It works wonderfully for cooking, and the half cup of grease will last for a half hour or so -- long enough to cook a fairly healthy portion of stew for a small gathering of wanderers.  The bottom of the pot will be coated with oil, but little soot, so clean-up is easy.

The difficulty is the supply of lightly pressurized air.  A bladder such as an old latex glove (often found in the trash wherever SPU checkpoints are placed) works wonderfully as an air reservoir.  An adjustment valve can be jury rigged from whatever is available, or, with luck, scavenged from discarded plumbing of some kind.  The adjustment valve is placed in the tubing between the can and the air reservoir to control the rate of air flow.  Constructing or finding an adjustment valve may pose a  minor challenge, but one easily solved by the resourceful wanderer.  The real technical  challenge to this stove is keeping the air reservoir inflated, without requiring the cook's assistant (if one is even available) to manually apply her lungs and lips to the job all the while the food is cooking.  The manual approach might do in a dire emergency, but is entirely too bothersome for everyday use.  To make the grease stove actually useful without an industrial air supply, another invention of the wanderers is needed.  That will be discussed in a subsequent posting, if there is sufficient interest in it.