Art. XI. Tips for Fast Fires with Flint & Steel, by J. Gottfred.
(See also "Making Fire with Flint & Steel")
Lighting a fire with flint and steel at public demonstrations can be a great way to kindle an interest in history. When you make a flame using two very unlikely-looking objects (a hunk of rock and a piece of metal), people's jaws drop in amazement— especially if you are fast. Demonstrations often include a flint and steel fire-lighting contest. The winner makes a flame in the shortest time.
In this article, I will give the reader already familiar with flint and steel some suggestions on how to light fires faster. I will explain exactly how flint and steel generates sparks, and then give some tips on how to increase your fire-lighting speed. (If you haven't yet lit a fire with flint and steel, you will want to read 'Making a Fire with Flint and Steel' (Vol. I, p. 2-7) first to learn the basics.) After reading this article, I hope readers will reach the point where lighting fires with flint and steel has become as quick and easy as using a match.
Just how fast are we talking about? In fire lighting contests, my best time has been eight seconds. Usually ten to fifteen seconds is all that is needed in order to go from the first strike to a flame. When I first started learning to do this, my times were much worse— two minutes or longer was pretty typical in those days!
Let's start right at the beginning— making sparks. Everyone is probably clear on the general idea : you hit a chunk of flint with a piece of steel, and sparks fly off. But what are the sparks?
You can easily answer this question by conducting an experiment. Lay out a piece of newspaper, and strike a few good sparks above it with your flint and steel. Then pick up the newspaper at the edges and carefully pour the contents onto a sheet of white paper. With the naked eye, it won't look like much— just a little dirty grit and some small rock chips. If you tilt the piece of paper, some of the small gray gritty bits scoot down the page much faster than the rest. The material can easily be sorted into two distinct groups (fast & slow) this way. Have a look at the fast guys with a stamp magnifier or jeweler's loupe. Behold! They are tiny balls : gray, shiny, knobby-surfaced spheres that look a bit like they are made from pencil lead. If you hold a magnet under the paper, the little spheres will roll and cavort, piling one on top of the other in the strong magnetic field. It is clear that they are made of iron.
Captured Sparks— These tiny spheres are formed as molten, white-hot steel flies through the air. These little globules are the sparks that ignite your tinder. (Image taken trough a microscope. Printed image 32X actual size.)
When the steel struck the flint, the energy in the blow was converted to the heat of friction between the rock and the steel. This heat was so great on some small portions of the steel that small, white-hot molten blobs flew through the air making glowing sparks. Incredible as it may seem, the spheres were made as the blob of molten steel flew through the air, making a natural spherical shape. (The sphere has the smallest surface to volume ratio of any three-dimensional object). As the tiny spheres cooled, solidified, and dimmed, they disappeared from view.
If you look with your magnifier at the other pile of material (the 'slow' pile), you can see all kinds of other forms. Some pieces of steel haven't melted at all ; they are just shavings. Others look like comets with a round head and one or more tails attached. I have even seen little strings of pearls : little spheres each a little smaller than the next, piled one on top of the other.
So now we know what the sparks are. They come from the steel, not from the flint. The flint simply acts as a knife, slicing off tiny shavings of steel. Does the rock have to be flint? The experiment suggests that the only requirement for the rock is that it must be hard enough to shave off bits of the steel, and not the other way around.
Geologists have classified the hardness of rocks into a scale from one to ten, with talc being the softest (1) and diamond being the hardest (10). Talc is so soft that almost anything can scratch it, including a fingernail. Diamond is so hard that nothing but another diamond can scratch it. On this scale a fingernail has a hardness of about 2½, a penny is around 3½, a typical knife blade is around 5½, and tool steel is about 6½ (Hamilton et. al., 10).
Fire steels vary in hardness from about 5½ to 6½, depending on their composition and tempering. Just because a fire steel is made out of tool grade steel or an old file does not necessarily mean that it has a hardness of 6½. The blacksmith who made the steel must re-temper its face to attain the ideal hardness.
The harder the steel is, the more difficult it is for the rock to tear little chunks out of it. To tear out small chunks of progressively harder steel, more and more energy is required. At some point, the energy required to pull a bit of steel from the face of the fire steel is so great that the steel is melted in the process, and a spark results. With a softer steel, slivers of steel can be cut from the face without generating enough friction to melt the steel. Little nearly-invisible shavings go flying, but no sparks are seen.
A fire steel with a hardness of 5½ will generate sparks, but they don't stay hot for long. A fire steel with a hardness of 6½ is capable of generating long lasting, hot sparks ideal for the fast ignition of your tinder. This explains why some fire steels don't seem to work very well— they may not have the right hardness.
What about the hardness of the 'flint' you use? Flint, chert, jasper, and quartzite all have a hardness of about 6½. Granites are in the 6 range. Obsidian (volcanic glass) is in the 5 to 6 range. Any of these rocks are strong enough to generate sparks. Many metamorphic rocks, especially quartzite, are also hard enough to generate sparks.
Although all of these materials will work, obsidian, quartzite, and granite quickly wear away and lose their sharp edges. Only the hard, non-grainy flint, chert, and jasper are strong enough to shave away the hardest steel and resist crumbling away in the process. Incidentally, chert, jasper, and flint are all different forms of the same mineral— chalcedony. They are all composed of precipitated silicon dioxide (Hamilton et. al., 130-131).
There is nothing magical about flint ; many other hard rocks will work to generate sparks. From a historical perspective, this suggests that Natives and fur traders found their own hard rocks to use to make sparks. I have never seen 'fire flints' in lists of trade goods. Flint, chert and jasper are the best rocks for fast fire lighting, and the harder fire steels are better.
Preparing and Holding the Flint
The idea is to use the flint like a knife to shave off tiny bits of steel. Bashing a billiard-ball shaped piece of flint is not going to produce many sparks, yet some folks do just that. The idea is to break that billiard ball so that you have a sharp edge. In fact, the best thing to do is to use a nice, palm-sized flake of flint, and keep its edge sharp by knapping it now and then with a small hammerstone. (See 'Making Stone Tools', Northwest Journal Vol. VII, pp. 30-37, for pointers.)
If you hold the flint in one hand with the sharp edge angled upwards towards the descending steel, the flint edge will slice off a nice shower of hot sparks.
The trick to generating hot sparks is not to hit the flint hard, but to hit it fast. The energy contained in the force of the blow is a function of the weight of the fire steel multiplied by the square of the speed. For example, if you hit a flint with a steel of one unit of mass with a speed of one unit of velocity, you will get one unit of energy. If you double the weight of the steel (or 'use more strength' by striking harder with the steel) then two units of mass times the square of one unit of speed will yield twice the energy. But, if you keep the weight of the fire steel the same, and double the speed, then one unit of mass times the square of two units of speed yields four times the energy.
So speed makes all the difference. It takes a while to get that flint up to speed, so don't use a short stroke with the fire steel! Tapping the flint with a twist of the wrist is not going to give you the energy you need. You must practice taking a long stroke at the flint, bending the arm at the elbow, and accelerating the steel through at least a foot of space before it contacts the flint.
One good stroke should be all you need. A good stroke with a good steel against a sharp freshly-knapped flint will produce extremely hot sparks that fly through the air for at least two feet, make a fizzing sound as they fly, and feel like tiny pin-pricks when they hit the back of your hand. That's the kind of spark you want to generate every time you use your fire steel. Incidentally, I prefer fire steels that are at least half an inch thick— it keeps your knuckles away from that sharp flint edge! For the same reason, I always strike the steel against a convex flint edge, never against a concave one. Use the steel itself to guard your knuckles.
Catching the Spark
Once you are generating hot sparks, you need to catch them with your charred cloth. There is a simple trick that I use which almost guarantees catching a spark on the first strike.
Consider again what is happening. The sharp flint is shaving off tiny blobs of molten steel— which side of the 'knife' are the savings going to come from? If you are holding the flint with the edge angled upwards towards the steel, and striking down with the steel, then the shavings are going to scoot along the top of the flint. Yet many people are under the impression that the sparks travel downwards from the point of impact. (This view makes perfect sense if you thought that the sparks were coming from the flint.)
To catch the sparks, take three or four pieces of charred cloth, fold it in half, and place the cloth on top of the flint so that the many stacked edges of the cloth are right next to the sharp flint edge. Hold the charcloth onto the flint in this position with your thumb. Make sure that the edges are 'fluffed up' so that you have a large surface area to catch the sparks right next to the flint edge.
One good stroke is all you need to catch a spark using this technique, and best of all, you can do it standing up, sitting down, in a canoe, or on a horse— it's much more convenient that crawling around on your hands and knees in the mud!
The 'Bird's Nest'
To make a fire, you need to have three things : heat, fuel, and air. The spark you caught on the charred cloth is your heat source, but you will need more fuel to make a flame. This is done by placing the charred cloth in a 'bird's nest' of small kindling (dried grass, paper strips, wood shavings, etc.) and blowing on it to create a flame.
Consider what is going on here. The idea is to generate heat, so tune your bird's nest to accomplishing that goal. Many folks start out with a bird's nest of dried grass that is the size of a robin's nest, and so loose you can see lots of daylight through it. This will work, but not in championship time! To get a fast flame, start with a bird's nest about four inches across, and squish it down into a tight compact mass. I use nests that are so small that I can hold them in the same hand as my flint.
You need to compact the small kindling so that it keeps in the heat that your charred cloth is generating. You don't need to keep it 'open for air' because you supply the air by blowing on it like mad! Use three or four pieces of charred cloth to generate heat fast.
The Fast Action
Now, here is how I light a fire in championship time.
Before striking :
— Inspect the flint, and knap the edge so that it is good and sharp.
—Find small kindling for your bird's nest. Nice dry grass works just fine for small kindling. Shreds of paper birch and wood shavings from your workbench are great too.
—Crush the small kindling so that the air spaces between the bits of kindling are one-eighth of an inch in diameter or less. Stuff the bird's nest into the palm of the hand that you will use to hold the flint.
—Take three or four pieces of 3" x 3" charred cloth, fold them in half, and place them on the flint as described earlier.
—Hold the charred cloth with your thumb, and support the flint with your fingers. The bird's nest will stay stuck in the palm of your hand, so you don't need to hold onto it at this time.
Now it's time to strike :
—Angle the flint upwards towards the steel.
—With a long, smooth motion, strike the flint with the steel.
—Drop the steel and pick up the charred cloth. Do not blow on the charred cloth at this time! The spark will not go out.
—Drop the flint (but hold onto the bird's nest), and using both hands quickly fold the charred cloth one or two more times to increase its density. Be careful not to smother the spark!
—Place the charred cloth in the center of your bird's nest, and then hold the nest above your face. Cup the nest with both hands in order to help keep in the heat. Some folks seem afraid to do this for fear getting burned. I assure you that the heat does not build up so fast that getting burned is a danger. (If for some reason the thing suddenly bursts into flame à la Hollywood, at least you have the satisfaction of having won the competition!)
The action so far should have taken you less than three seconds.
From this point on things are a bit more chancy. How fast you get a flame depends upon what you have for kindling and how dry it is. Remember that it is very important to hold in the heat until you have a flame. Keep those hands cupped around the birds nest!
I have found that the best way to proceed at this point is to give the dense piece of charred cloth a long, strong blast of air. Just empty your lungs into the thing. This action will turn the charred cloth into a little nugget of hot coal. If, when you pause for breath, you don't have a flame, then blow again, but perhaps somewhat more gently. However, at this stage too much wind is better than too little wind. When you pause for breath a flame will appear if things are hot enough. Remember, blowing will not make the charred cloth go out!
All of this blowing is another good reason to do this standing up. You can hold the bird's nest over your head so that you don't choke on smoke when you inhale ; also, you are in a great posture to let out a good blast of air. Two or three good puffs of air should be all that you need to get a flame.
If blowing makes you faint, and you are not doing this in competition, there are a couple of other methods you can use. You can fold the bird's nest around the charred cloth, and then simply lift it up into the wind. If there is no wind then you can simply wave it back and forth for a while. This will usually produce a flame in a minute or so. Or you can take a tin can, punch a whole bunch of large holes in it, and attach it to a string. Pop your bird's nest into the can and whiz it around with the string for a while until it bursts into flame.
When you have learned these methods for flint and steel firestarting, there is one more thing you can do to increase your speed : practice! The more you use flint and steel, the more natural and familiar flint and steel fire starting will become. Furthermore, flint and steel has two major advantages over matches : it is windproof and childproof! (It can be a bit messier, though.) Use your flint and steel to start campfires and fireplace fires year round and you will be in top form the next time some cocky voyageur challenges you to a contest!
Hamilton, W.R., and A.R. Woolley, A.C. Bishop. The Hamlyn Guide to Minerals, Rocks and Fossils.Hamlyn Publishing Group : London, 1975. ISBN 0-600-34398-7.
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