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About Making Fire

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Anthropologists tell us that making fire was a major step forward in primitive man’s development. It's said this achievement was so important that it is memorialised in the mythologies of all the ancient civilisations with stories of godlike fire givers and fire thieves. The ability to make fire allowed man to control his environment for the first time: to push back the dark, provide heat, and protection against predators . If you are ever forced to survive a cold night outdoors without a fire, you'll learn very quickly that making a fire quickly and reliably in a variety of threatening environments can save your life, particularly on a hostile coastline in cold windy conditions with a hypothermic casualty to care for. Just like that primitive ancestor, with the ability to make fire you can provide light, heat, and protection at will. You can also cook and sterilise your food and water, warm cold bodies and signal for help. Talk about taking control and feeling empowered in a tough situation!!

So how hard can it be to start a fire? With good weather conditions, the right tools, materials and methods; it's not hard at all. But how many times have you witnessed grown men with newspaper, dry wood and a lighter struggling to light a barbeque? And that's on a balmy day in July!! Are you sure you could do better on a cold windy beach with everything damp and under pressure with first stage hypothermia or a member of your group in rapid decline. So let’s imagine that needful moment is here but before we get into the art of actually starting and building a fire lets us first consider some things about the nature of fire; that is how combustion works physically.

Fire is in fact a wonderfully complex thing; a full understanding requires knowledge in thermodynamics, heat transfer and chemistry. I'm not going to go that deep here but the diagram (attached image) will help keep things easy to understand and remember! The triangle illustrates the relationship of the essential components for a fire: FUEL, HEAT, and OXYGEN. The triangle's connected corners symbolise the interdependence of these three critical components; reducing or eliminating any of these will prevent a fire from starting or continuing to burn. Basically, any FUEL (combustible material) supplied with enough OXYGEN will be set on fire if it absorbs enough HEAT. So you've got the Zippo (heat source) and air is about 20 % oxygen; find some wood and you're set, right? You should be so lucky!

As a sea kayaker on a beach the biggest challenge will be moisture; that is moisture inside every piece of combustible material around you, even in “kiln dried firewood” water makes up 12 % of the total weight. At this point it's important to remember some grade school science about water. First, drying water (applying heat to change it from liquid to vapour absorbs a very large amount of heat and the resulting steam pulls heat away from the fuel and keeps it from reaching its ignition temperature. Second, steam is a gas and it can displace the air around the fuel and further inhibit the combustion process. Even with a Zippo, unless you've got a liquid fuel or solid fuel blocks, you'll need tinder: material that’s finely fibered, very dry, and easily ignitable. All fire starting techniques rely on it and except in desert environments, dry tinder is scarce. The importance of tinder can't be overstated! Learn where to find it (articles on tinder will follow), how to make it if necessary and how to store it. Tinder dries easily because it's surface area is large in comparison to its volume. This small volume and its low water content means you'll need less heat to raise its temperature up to the point of ignition. Once a piece of the tinder ignites it provides heat to ignite its neighbours..

The heat generated from the tinder bundle or stack is used to ignite small twigs, and then their heat to ignite small sticks. This “smaller to large” process is used to ignite increasingly larger pieces of fuel. It is a core principle of all good fire designs. Also always remember that hot gases rise and cold gases drop. Most of the heat from a fire is being released upwards; that's why it's always best to put your tinder bundle in low with increasingly large pieces of fuel stacked above it. That way the rising hot gases can warm and dry the fuel that's above. But always take care not to crush down on your tinder; remember no oxygen means no fire! In fact the same idea applies to the whole fuel stack, always leave open cracks between the pieces of fuel. The cracks should be about the same width as the fuel you're stacking. With very damp wood it's best to feed the fire by hand, that is to sort out the fuel by sizes, and after igniting the fire bundle feed in increasingly larger pieces of fuel slowly and carefully. 

Also be aware that any cold or damp surfaces that are in close contact with your fire will draw away heat energy. Cold stones draw a lot of heat as do large pieces of damp wood and the wet ground as well. These types of surfaces can quickly cool the smoke of the fire bundle; the cooled smoke doesn't rise quickly and can choke the small flames. Be aware of strong winds that can scatter your tinder or the sparks, coals or small flame from your fire starter. In windy conditions, work close to a barrier or crouch down and use your body to block shield your flame. In very damp and cold conditions try to prop your tinder bundle above the ground, use a small bed of sticks lined up side by side, or some flat stones if they're available.
Good camp fire design is based on an understanding of the physics of heat transfer or movement. Heat always moves from hotter regions towards colder ones. The bigger the temperature difference, the faster the heat moves. It only has three ways of moving, conduction, convection, and radiation. In a camp fire, conduction causes the opposite end of a lit stick to get warm, that is the heat has traveled through the wood. For our purposes convection relates to the hot gases rising from the fire or the cold wind that's chilling our body; it refers to the heat to moves between a moving gas to a solid object. Most of the heat we can feel coming from a fire is getting to us by radiation; the fire is literally putting out microscopic heat waves. All warm bodies do this, the same way the sun heats the earth through 93 million miles of space!

So now you've had all of the science behind fire, the key is to be prepared, carrying a watertight container with a number of fire making tools and methods as well as a combination of good tinder for fire making in damp and even wet conditions. Our next article will look at types of tinder and how to carry it.

 

 

 

 

Published On: 18th November 2015