Yes, there really are three ways to get fire from a flashlight. For the first one, we need to stack the deck in our favor with a simple trick. Put a book of paper matches inside the flashlight housing on large bodied flashlights.
The next two of the methods of fire starting are based on useful properties of flashlight components, namely an electrical fire with the battery and an optical fire using some tinder and the flashlights mirrored cup. Here are the specifics you need to know for each method.
Using the matches is easy and obvious. Select good ones, and snuggle them down inside large flashlights. This keeps the matches relatively dry, and available as a backup, without interfering with the flashlights operation. The match book may not fit in most lights, but its always worthwhile to explore back-up gear techniques like this.
Battery & Steel Wool
To use the battery for fire, youll need a special ingredient. Youll need steel wool, which should be carried safely in a dry location away from the battery. The battery and steel wool trick is a neat one. Using a 3-volt or higher voltage battery (or stack of batteries) and some fine steel wool, you can quickly produce a burning ball of steel fibers. This burning steel can then be placed into tinder.
The pros to this technique are that many different sizes and types of batteries will work for this application. Different grades of steel wool can work too. The grades from 0 to 0000 will work well. Just look on the package for zeros.
But there are some down sides to this technique too. The steel wool wont work if it has rusted, or if it’s wet. A dead battery wont work either. If the battery is good, the sparks should fly right away! And they should never be stored near each other, or they could light up in transit. Also, fine grade steel wool is hard to find outside of a hardware store.
Fire From Light
Using the mirrored cup of the flashlight takes me back to burning ants as a child. The mirror acts similarly to the magnifying lens, by concentrating light to produce heat. Youll need some fine tinder, like fluffy plant based fiber, but a cigarette will work too.
Youll need to carefully remove the mirrored cup from the flashlight, remove the light bulb, and store it someplace safe if you plan on using the flashlight again. Then insert the tinder where the bulb formerly sat, and face the cup into direct sunlight. Get the right angle on the cup, facing it directly into strong sun, and it will smoke the very second that you got the zenith and azimuth right. Youll need to blow gently on the smoking tinder while it is in the cup, and after you remove it from the cup, and again when you place it into the tinder that will create your flame.
One big pro for this method is that it works great when the sun is strong, the lens is big and clean, and the tinder is fine quality and dry.
The con is that you need direct strong sunlight and great tinder. No, the moon, nor a different flashlight will not work. Sunlight only, please. Here is a video that shows how is this working.