Friction Fire

The science behind rubbing sticks together to make fire

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It looks so simple in the movies… simply rub two sticks together to start a fire. Many have tried and nearly all have failed to start a fire this way. How did pre-historic humans make fire? Can you really make fire by friction? Steve Spangler attempts to answer this question with outdoor survival expert, Ford Church.

Here's What You'll Need

  • bow
  • p-cord
  • spindle
  • fire board
  • socket
  • rock/wood handle knife
  • tinder
  • coal catcher

Experiment

  1. Bow- The bow should be approximately the length from your arm pit to fingertips. It should be slightly curved and slightly flexible. It is easier to tie if there is a crotch in one end. Any type of wood can be used, although green wood should be avoided.
  2. Bowstring- The bowstring should be approximately one wing span long. Parachute cord, braintan buckskin thongs, shoelaces, and natural 2-ply cordage all work well. The string should not be tied too tight so you can’t put the spindle in, but also not loose to where the spindle will not rotate.
  3. Socket- The socket should fit comfortably in the palm of your hand and is used to apply downward pressure to the spindle while creating friction to the fire board. Stones, bones, shells, and hard woods can be used as sockets. Small notches or holes are drilled into the socket to create the least amount of friction where the spindle and socket meet, so choosing the right materials are key. The socket can also be lubed with oils from your face, earwax, lip balm, and other lubricants.
  4. Spindle- The spindle is one of the most important pieces of the fire set. The spindle should be the width of your finger and the length from your pinkie to thumb when your palm is extended. The spindle should be created from dead and downed Sagebrush, Juniper, Cottonwood, Aspen, Cedar, and other softwoods. The end applied to the socket should be longer and pointed to reduce friction and the end applied to the fire board should be short and blunt to increase friction. The spindle must be straight as an arrow.
  5. Fire Board- The coal of a friction fire is actually born from the fire board. The fire board should be about two fingers wide, one finger high, and as long as your pinkie to thumb with your palm extended. The fire board should be as soft or softer than your spindle and an impression should be left after piercing it with your thumb nail. Fire boards can also be created from dead and downed Sagebrush, Juniper, Cottonwood, Aspen, Cedar, and other softwoods.
  6. Coal Catcher- The coal catcher is placed underneath the fire board to catch the coal after it is produced to be transferred to the tinder bundle. This can be created from almost anything flat. A piece of bark works well.
  7. Tinder Bundle- The tinder bundle is the most essential element in making fire. It is used to blow the coal from the fire set into an actual flame. The tinder bundle should be finely shredded and resemble a bird’s nest at least the size of a fist. Fluffy and fibrous materials are key. Juniper bark, Sagebrush bark, Cottonwood bark, crushed grasses, and crushed pine needles make good tinder. Cattail down, Milkweed silk, and pocket lint make good coal extenders, but are difficult to ignite. You should make a tinder bundle by tying your material in an overhand knot and then tucking the ends towards the center. The tinder bundle should be tight and the outside should be coarse while using progressively finer material in the center of the nest. The finest sawdust material should be put in the nest last and it will mark the place where the coal will be placed.
  8. The Fire Board Notch- The notch is what allows the fine powder to form into a coal during friction fire. The notch should be about the size of 1/8 or 1/6 of a pie wedge throughout the entire thickness of the fire board. Start by marking your fire board with exactly where your spindle will be burrowed into the fire board. The hole you burn should be at least a millimeter from the edge of your fire board, but not in the center. Use your spindle to burn a hole the width of the spindle into the fire board before you carve your notch. Then use your knife to mark the exact center of the burned hole and make a mark on the outer edge of the fire board. Begin cutting your notch on both sides of your line in a pie shaped wedge. The notch should almost go to the center of the hole you burned with your spindle, but not quite. The notch should be widened on the bottom of the fire board to allow the fine powder to collect. If you begin drilling and the punky material collects on the top of the fire board, reexamine your notch. You may have to widen the notch or make it deeper towards the center of the spindle hole.
  9. Body Position and Technique- A direct line of pressure is key to a successful bow drill fire. Your chest, knee, and wrist should all be directly over the spindle to use your body weight to apply the necessary downward pressure. If you are right handed, begin by placing your left foot approximately 1 finger width away from the notch of your fire board using the ball of your foot. You should be in a kneeling position with your left knee bent while baring your weight on your right knee. Your left arm should hug your left knee and you will hold your socket in your left hand as well. It is important that your left wrist is firmly locked against your shin. If your wrist is wobbling while you are bowing, you will not be proficient in producing a coal. When the spindle is in your bow, rock your weight forward giving the direct line of pressure over your spindle.
  10. Creating a Coal– Before you begin to create a coal, you want to make sure that you have gathered enough material to make your fire including kindling the size of a match stick to wrist sized wood. A tepee of kindling should be prearranged with one side open to receive the tinder bundle. When you are ready to make a bow-drill fire, begin with long bow strokes at a slightly diagonal angle. If you bow perpendicular to your fire board you will tend to hit your knee and use a shorter bow stroke. Begin with nice fluid strokes and slowly add more pressure to the spindle. Keep the bow as level as possible so your bowstring does not ride up and down your spindle. When you begin to heat up the fire board and you see smoke, increase the pressure and the speed at which you are bowing. A charred sawdust material will be produced at the base of your notch and a coal will be produced when the pile of punk reaches a temperature of 800 degrees F. You know you have produced a coal when the smoke begins to billow from the bottom of the fire board as opposed to the top. Don’t forget to breathe when you are bowing – you need oxygen too!
  11. Blowing the Coal into a Flame- When you have successfully produced a coal, use a knife point to gently separate it from the fire board and take a deep breath. Tell a joke, prepare your tinder bundle, and take your time because the coal will grow stronger with a little room to breathe. You may also gently fan the coal, but don’t rush things or you risk dropping the coal. When you are ready to blow the coal into a flame, gently take the coal on the coal catcher and place it gently on the fine sawdust section in the middle of your tinder bundle. Gently close the tinder around the coal with both hands cupped around the nest and hold it skyward to avoid inhaling all of the smoke. Blow directly on to the coal forcefully and consistently to allow the coal to spread and ignite the tinder. When your tinder bundle is aflame, place it in the prepared tepee and carefully add larger pieces of wood.
  12. Extinguishing the Fire- Coals may never biodegrade in the desert, so great care must be taken when extinguishing a fire. All fires should be burned until it is reduced to white ash. Unfortunately, this is not always possible so all coals must be completely crushed and scattered without a trace. Ideally, water should be used to douse all fires to ensure that the fire is completely out. When the coals are cool to the touch, rocks should be used to crush all coals. The pulverized ashes should be scattered at the base of trees and shrubs to fertilize them and promote growth. The fire pit should be mixed with sand and other organic material to make a fertile growing area and covered so that the fire area blends with its surrounding environment. Finally the stones used to crush the coals should be cleaned and disbursed.

At the request of the author (Ford Church), we have added this copyright notice:
Copyright © 2006 Cottonwood Institute, Inc. All rights reserved. Please contact the Cottonwood Institute for permission to use or reprint this lesson plan.

Additional Info

Thanks to Ford Church, Founder and Executive Director of the Cottonwood Institute in Boulder, Colorado for this information. The mission of the Cottonwood Institute is to inspire students how to change the world through an exciting blend of adventure and service. They teach students essential camping and wilderness survival skills, including how to make friction fire. For additional information, call 303.447.1076


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