There are three basic components to a magnesium fire starter stick: magnesium, flint and carbon steel. The large, light grey portion is the magnesium. The narrow dark cylinder embedded in one side of the magnesium is the flint rod. The third part of the tool is a separate piece of carbon steel that resembles the blade of a jig saw.
To get a fire started, use the toothed edge of your saw to peel some shavings onto the finest fibers in your tinder nest. Try not to gouge chunks out of the bar. The thinner the shavings are, the easier they are to ignite. Work in an area protected from gusts of wind as these shavings are feather light. If using a knife, utilize the back edge so that you don’t dull the blade of an important tool.
Some instructions recommend creating a dime-sized pile of shavings, but with a well constructed tinder nest, you’ll likely need less. A pile of shavings equal to the size of a pencil eraser may be enough. I recommend that you start with the smaller size and add more shavings if necessary. In this way, you are able to extend the life of your tool.
Hold the magnesium starter in your less dominant hand with the dark flint bar turned upward. Hold the saw blade in your dominant hand, pinching the flat of it between your thumb and forefinger. The narrow edge of the blade will extend just beyond your fingers. Run the short side of the carbon tool across the flint in a downward stroke towards your tinder nest and magnesium shavings. You should immediately see sparks. If they don’t immediately catch, move your hands closer to the magnesium shavings so that there is a better chance of ignition. Hesitate long enough between strikes to check your tinder for a flame.
Another way to coax a spark is to hold the jig blade steady and pull the flint towards your body as you scrape it across the blade, directing the sparks into your tinder bundle. Experiment with both methods to see which is most comfortable and effective for you.
Neither shaving the magnesium nor striking the flint will require you to etch deeply into your tool. If you aren’t having good success and notice that there are deep gouges or an edge that’s worn flat, try a lighter touch.
Don’t risk holding the tinder nest in your hands when striking a spark with magnesium. It burns so hot that a flaming piece of magnesium could easily burn through human skin all the way to the bone. Instead, allow the magnesium shavings to flare and catch the tinder. THEN you can hold the nest and gently blow, feeding the flame vital oxygen.
Remember, the adrenaline rush of urgent circumstances can decrease fine motor skills, so take the time to get familiar with your fire stick before there is an emergency. Magnesium fire starter sticks can be found at most outdoor retailers for $2 or less. Purchase two of them and practice with one until you are comfortable with it. This small investment of time and money has the potential to save your life.
Here’s a video demonstration of how to start fire using a carbon steel knife with a magnesium fire starter. I don’t recommend gouging at the magnesium in this way, but the process is forgiving and worked for him.