It transpires that when my wife says I've got every thing for camping that doesn't always include food for me!
To this end I've started to build a what appears to be called a bug out box, It started as a stash of tinned and packet food in my car. I brought a solid fuel stove and set of mess tins so I can cook it should I get stranded somewhere in my car. The hexamine fuel tablets aren't exactly cheap, which got me thinking what could I use instead.
I've experimented on 'T' lights in the past, whilst the wax fuel pellet they use theoretically contains a lot of energy the wick they come with is designed as a long burn slow release method of using it, by my estimations the power out put of a standard 't'light is about 25W, The ones I've experimented with burn for about 90 minutes and have so far failed to get 200ml/7Oz(1cup?) hotter than 90c in that time, 10c short of boiling.
The redesigned wick I've used managed to heat 500ml to about the same temperature in 10 minutes.
A quick bit of maths says the modified 't'light is producing about 240W or about 10x the energy but only 1/10 the burn time.
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Step 1: The Stove
The stove I Purchased is basically a slightly flimsier version of the standard NATO ration pack stove from 25 years ago. The box claims one (25g) fuel pellet can boil 2&1/2 cups (500ml?) in 5 minutes. I also purchased what appear to be a set of NATO mess tins at the same time, the whole lot cost me just under £10 at my local camping shop.
Step 2: Testing
I set my stove up OUTSIDE, yes hardboard probably isn't the best thing to use as a wind break but it survived. I put 500ml of water in the tin put it on the stove use the larger tin as a lid lit the fuel pellet started the stop watch and waited.
As advertised the fuel pellet burnt for pretty much 5 minutes and the water was at 100c according to the thermometer when it went out, it wasn't quite a rolling boil but close enough I think.
I threw away the boiled water cooled the tin in the water butt to get a fair test and set up again.
This time I used the foil tray from an old 't'light and filled it with methylated spirit (90%alcohol with some methanol, bittering agents and dye so you don't try drinking it) it held 15ml about 1/2Oz, I lit that and left it to burn out. Ok it's not a penny stove but it does give me a benchmark for to how good just an open alcohol flame is at heating water to compare a penny stove to when I do eventually make one.
The result after 5 minutes (because that is how long the commercial fuel tablet took) 55c it burnt for a further 7 minutes but only reached 64c. I personally think a wider shallower tray mounted closer to the base of the mess tin would be much more efficient but that is another experiment.
I reset as before and tried the modified 't'light. (wax pellet 10g)
After 5 minutes the water was also at 55c same as the alcohol flame, after 7 it looked to be dying so I checked again 72c, It burnt out at 10 minutes at which point the water was 87c. Not boiling but hot enough for coffee and you'd want to let soup cool down from that so I'd say its a success.
Step 3: The How To
I used paper kitchen towel, but I think facial tissue, toilet paper or a strip of a cotton T shirt would do as well, I measured how much of a 't'light wick is actually there if you blow one out (about 3mm) decided on the basis of prior experience a double thickness of paper would be needed, and arrived at a required width of 35mm being close enough (15+3=18x2=36) folded the strip half, as it is easier to work the base of a V into the case than just a single edge, don't know why but that is my experience.
The 't'lights I'm using split neatly into 3 parts the wick and it's base the foil case and a wax fuel pellet
Wrap the doubled strip around the wax pellet, cut it to length, too short is better than too long, an overlap makes getting it back in the foil case rather harder than it should be.
Put the wrapped pellet back in its case, you need the original wick to be in place as well. To do this if you start with the joint and rotate the fuel pellet as you push it back into the case the paper new wick gets drawn in with the wax.
Now the hard/ dangerous part light the original wick without lighting the paper, let a pool of molten wax form then swirl the case so it is absorbed into the paper new wick, at this point if you are needing it straight away you can transfer the flame to the new wick, if you are prepping blow it out and let it cool before storing. I made up 6 for my tests after I'd tried the first couple, I actually melted a small amount of wax in another old case and poured that into them and swirled it to wax the new paper wick.
Step 4: Initial Tests
I seriously underestimated just how smokey this is. I actually lit the first one in the kitchen and tried to heat 200ml of water in the same way I had with just a normal 't'light set off the smoke alarm and decided it was better to try it out side. Both the paper version I've given instruction details for and the ring of corrugated cardboard version I haven't burnt quite vigorously until they had exhausted all the wax despite the fact it was actually raining. There was little difference in burn time so the ease of construction is what has caused me to favour the paper wicked version.
The highly visible flame and large amounts of soot mean that the wax isn't being fully burnt a lot of the potential energy is being lost because of this. I need to revisit my