Intro: Ultra Lighweight Alcohol Burning Emergency Stove (also Good for Backpacking, Day Camping, Etc.)
Using a pair of soda cans, cut the bottom sections of each. Soda can aluminium is so thin you can cut it using scissors. Leaving one soda can bottom as is for the bottom half of my fuel tank / burner. It is preffered to do all the drilling for the top section of the burner unit before cutting off the bottom section from the can. The other section of soda can bottom is hole saw cut on the center of the depression or dimple of the can. Second, transfer an hexagonal ray pattern onto the edge of the soda can under work ( this soda can bottom will become the top part and working burner of the stove ). On the marks transferred, use an oval file ( prefferably a jeweler's file ) and file six oval holes. Using another template: transfer the pattern for the small round holes for the burner half of the stove. Using a 1/16" drill bit on my Dremel (or any lightweight corded or cordless drill) tool, drill the five holes per six spaces between the oval holes I filed before. That gives me a total of 30 holes. These are the jets for the flames of your stove. The bottom section that remains untouched gets its walls slightly crimped. The top section, already drilled, gets a prepared brass mesh ( mesh # 100 ) disc cut to fit the interior of the soda can section. A piece of glass wool gets inserted into the bottom section of the burner. To the crimped section, apply high temperature silicon sealer ( the type used for gas engine blocks, RTV type ) all around its circumference and push this bottom section inside the not crimped top section, until both can not be squeezed any further. With your index finger inside the hole saw cut hole, squeeze the crimps of the bottom section against the wall of the outer (and also the top ) section to achieve a tight seal. This is important, because you want to prevent fuel leaks from the joint of both parts. Special care has to be exercised when doing the squeezing of the crimped walls to avoid getting cuts on your finger (s). Next you cut a strip of the same aluminium material from the soda cans you've been using to fabricate the fixed funnel for the stove. Take measurements from the top of the big hole (in the center of the burner part ) to the bottom of the burner, Add from3/32"to 1/4", this will be the width of the aluminium strip you'll be cutting, rolling and inserting into the funnel hole to make it fit. The excess of funnel strip should not be more that 3/32" above the edge of the funnel hole. Once you get the final fit, make three " v " shaped cuts at the end of the funnel tube, this will be the bottom edge of the same, insert it into the funnel hole and apply silicon to seal the joint between the funnel hole and the funnel tube. Put this assembly aside for 24 hours to allow the RTV silicon to cure. This will be called the burner unit. Next is the tin box to be modified to become the stove housing, proper. Using a tin box measuring 4" X 4" X 4" drill evenly distributed 1/4" holes alogside the bottom of the tin box. Centering the bottom of the sane tin box, Place the top part or removed lid of a soda can, one that was used to fabricate your burner, slit with a utility knife the attached aluminium walls and wearing leather gloves and using a pair of pliers, pell of the aluminium walls ( or skin ) off the top lid of the soda can. p;ace this lid centered ont inside of the bottom of the tin box. Mark for two holes to be drilled on the lid as close to the lid's center as possible. Drill using 1/8" drill bit and place the drilled lid onto the interior bottom of the tin box. Mark one hole first onto the bottom of the tin box and drill using 1/8" drill bit. Attach the pre-drilled lid to the bottom of the tin box using one "pop" rivet of 1/8" X3/16" long. Check before riveting, that the lid is properly centered on the bottom of the tin box. Secure this rivet. Now drill the second hole on the bottom of the tin box following the previously drilled hole on the lid that has not been riveted yet. Then secure the lid on its second hole to the tin box. A reminder, push the rivets from the exterior onto the interior of the tin box. The comes the grille, to support the pot to cook on.. Using a piece of oven grille, measure the height and width of the tin box. Multiply 2 times the height of your tin box and add the width, plus three inches. This will give you the rough dimensions for your stove's grille. Center the width on the piece of grille to work on.and bend to get a free standing grille. Cut and trim until you get a grille that is 3/4" above the top edge of your tin box. Remember your grille will have four legs, and may look like an insect from another planet but it will do its job as long as you keep the trimming even for all four legs. Now this is it for the fabrication of this alcohol stove. Let's test it. After the curing has been complete for the RTV silicon, pour ethyl alcohol (70% alcohol, the one similar to what you get in a drugstore or hardware store) until you see a slight overflow from the funnel tube and the top section's dimple is under alcohol. Cover your alcohol bottle and put it away, alt least five feet away for safety. Set the burner into the tin box seating the burner onto the lid. Set the grille onto the tin box. Light the alcohol and see the stove warming up, it should take approximately between 5 and 10 seconds to reach maximum temperature. You will notice the jets firing the flames which will bear a blue to purple colour. that is clean combustion. Careful! the temperatures I have recorded from my prototype range from 1,200 deg F to 1,600 deg F. Nevertheless, the burner unit stays at a cool 400 deg F. This testing stage is very good to check for fuel leaks, which will show as flames coming from the side of the burner unit. Not to despair, let the fuel burn completely and after the burner unit has cooled to room temperature, ( that takes less than two minutes after the flames have died out ) Apply a thin coat of the RTV silicon all along the seam or joint between the two sections of the burner unit. In the future, I may be able to include short videos of the fabrication of both the burner unit and the stove housing. If the pictures I have upload satisfactorily, these instructions will make a little more sense, if not patience my friends, you may send me a message to my in box. I will be glad to answer specific questions related to the fabrication of this stove and the testing of the same.