|A fire can, ready to light.|
|Wax from four tea lights ready to pour.|
Cut out cardboard strips around the same height as the top of the can. Roll 'em up and put them in the can.
Melt the wax down--a double-boiler is going to be the safest and fastest.You're not supposed to melt wax over an open flame due to fire risk. I just put a nesting GSI cup in a pot of boiling water. Melts down in a couple minutes, easy stuff. Then I Poured the tealight wax over the cardboard and let it cool and firm up.
Next comes the fun part - fire. The fire can is NOT going to be lit with a ferro rod alone--you'll need some actual flame to get this started. A lighter will take 10-20 seconds or so of direct contact to really get it going. I settled for a bit of cotton ball lit with a ferro rod. That got it burning, and the flames gradually spread from the center of the roll on outward towards the edges.
The fire can puts out quite a bit of heat and a pretty good sized flame. It's certainly something that you could cook with - a fire can plus a vented #10 can would make a good hobo cook set. The can was outside with a 5-10 mph breeze and burned well, not threatening to burn or snuff out prematurely. Total burn time was 75 minutes, with the flame only noticeably shrinking towards the end.
A couple thoughts. I think the can that I used was too tall--the fire cans in the survival books I've seen are usually based off of a shoe polish tin or a small tuna can. The top of the cardboard roll is really what burns, so in this particular can, the lower 1/2 to 2/3 of the roll was useless. Shorter cans would seem to be better. I would also want to explore what adding more wax would do--this particular can probably did not have quite enough wax for its size.
Were I to pack these for a survival kit, I would make sure to include a candle wick in the build process or a bit of some kind of tinder on top. Something to ensure that you could light it when the chips were down.
While the fire can is worth a try, it's a bit of a niche piece of equipment. The fire can is not going to burn all night, so in a cold weather survival scenario, you're going to need to build a real fire at some point anyways. That relegates the fire can to a cooking role, where I would prefer a soda can stove or gel fuel can like a Sterno, or just cooking over a fire.
In most survival scenarios, I would prefer the tea lights over the fire can, too. Tealights burn for around 4 hours a piece and can be used for warming or starting a real fire.
That said, the fire can is not without its uses. In an urban environment or in a hide site, you may not be able have a full-fledged fire, and if you had no other stove options and a surplus of wax, this might just be the ticket. Or perhaps in a rain/winter scenario where you could not get a fire going otherwise due to dampness, lack of tinder, etc. A burnin' fire can should be enough to get a fire going most anywhere.
Fun little project that only costs you some wax and time. Certainly worth knowing how to do even if you never need it.