Fire: experimenting with a bow-drill

I always wondered as a kid how you could get fire by rubbing two sticks together.  It’s always presented that way, you know?  Rubbing two sticks together–like you just pick up a couple of twigs and pretend to whittle one with the other, and then all the sudden they burst into flame.  Not so.  I’m sure you know that it’s not so, but how many people know what is so?

Somewhere along the line, I gathered enough information to know that there was more involved than just two twigs off the forest floor.  I think it was a picture in a history book of a tan-skinned man with stringy black hair hunched over a tiny machine made of whirling wood parts that he held in place with a bare foot and actuated with something that looked like a hunting bow.

That little wooden machine is known as a bow drill, and what a marvelous machine it is.  There are only a few parts to it.

  • The bow
  • The bow string
  • The spindle (or drill)
  • The fireboard (or hearth board)
  • The hand-hold (or socket)

In fact, the bow-drill is an improved design upon an even simpler machine called the hand-drill which has only two parts: the spindle and the fireboard.  In my study of these two fire-making devices, I determined that the simplicity of the hand-drill may be wonderful for those who already know how to twist fire from wood, but I figured the efficiency of the bow-drill would be more friendly to my novice hands.

I’m sure you understand the principles behind the process of getting fire from wood–even if you don’t know that you know.  It’s all about friction.  You’ve rubbed your hands together to warm them on a cold day.  You might have let a rope slip through your hands in gym class and felt the heat in your skin.  When molecules collide with pressure and force, they bounce off each other and transfer that kinetic energy into their neighboring molecules, causing a molecular bounce-party that we interpret as a rise in temperature.

The concept of using a bow-drill is seemingly simple enough:

  1. Twist your bowstring around the spindle.
  2. Hold the spindle in place on the fireboard with your socket.
  3. Saw back and forth with the bow which twists the spindle, causing it to rub against the fireboard and produce friction.
  4. The friction wears fluffy, little particles of wood powder off of the spindle tip and the fireboard.
  5. When there is enough heat (about 800º F) from this entire process, an ember is born in the powder.
  6. Transfer this ember into a nest of tinder–extremely light and flammable material that the ember will catch on fire.

Understanding the principles, though, was just the beginning for me.  I began to pour over information from various sources: Thomas J. Elpel’s Participating in Nature, Tom Brown’s Field Guide to Wilderness Survival, Urban Scout’s videos, Sassmouth’s blog on his bow-drill.  I even swiped a bow-drill article off to put on the Rewild.Info wiki field guide.

After lots of reading, all of which was really exciting me toward experimentation, I realized it was time to give it a try.  I knew from my readings that soft wood is preferable to hard wood.  In fact, the thumbnail test seems to be a pretty good measure for whether the wood in question will work:

For an easy, quick fire, the fireboard and the drill both need to be some kind of light, dry, non-resinous wood. The friction required to generate fire with two pieces of green wood or hardwood is enormous! The best wood for this won’t have any sap, and will be light and soft enough to easily dent with your thumbnail without gouging.[1]

In reading through my sources, as well, I saw mention of various species of willow.  Since I had quite a few branches of willow in my back yard of various sizes, I decided to give it a try.  The willow passed the thumbnail test, so I proceeded to cut some pieces that I thought would work for my set.  I wanted the spindle to be about as thick as my thumb and as long as my hand-span, and I wanted the fire board to be about three inches wide, about a foot long, and half an inch deep.  Finding a straight branch for the spindle was easy.  For the fireboard, I decided to cut a section off one of the larger branches I had in the brush pile and use my hatchet to split out a plank of the desired thickness.  For the bow, I found a curved piece of sycamore that someone else had put in the brush pile.

Far end with knotOnce I had my materials, I sat down on the front porch and began to do some crafting.  The bow was the easiest to make.  I simply sawed or cut off the protruding limbs and then cut a notch across the diameter of each end of the bow.  This allowed me to tie a knot in one end of my cordage (a piece of nylon clothes line–hopefully to be replaced some day by natural fiber cordage) and let the knot hold the string at one end of the bow.  Far end with knotThe other end of the string fed through the notch at the back of the bow and was wrapped around the bow to provide variability as the cordage stretches or in case I might need a new spindle.  My thanks to Sassmouth over at Dynamite Skills for the inspiration in making a bow with a variable string.

The spindle didn’t require much work.  Once it was cut to the desired length, I removed the bark and sharpened the ends by whittling and filing them against the concrete of the sidewalk (which I figured could be analogous to filing it against a piece of sandstone in a primitive situation.)  Willows tend to have a lot of small limbs on each branch, so there were also a lot of knots in the wood that I had to smooth down in order to keep them from wearing out the bow string.  I found that a sharp hatchet is an invaluable tool in whittling, as it allows you use much more force and take a lot more wood off the object than you could do with only a knife.  Far end with knotHowever, you can’t get very precise when whittling with a hatchet, so I used a combination of the two tools to debark the spindle and knock off the knots.  Also, I tried to smooth out the roundness by filing the spindle laterally against the side walk.  Unfortunately, I did not take pictures when I first made the set.  However, this picture allows you to see how much material has worn off the spindle since I first made it, as it originally was cut to the length of my hand span.

In order to cut the fireboard out of the log, I placed the log on end, set my hatchet blade at the point where I wanted to start the split in the log, and used a hammer to drive the hatchet through the log.  I found this method to give me more control over where the log split than if I had simply tried to split the log with the hatchet alone.  It took two splits like this in order to split out a plank or shingle of wood from the log.  While the plank is not as uniform or smooth as the fireboards I have seen others use (which often look like a piece of treated lumber), it serves quite well and provides differing thicknesses and textures against which to try the spindle.

For the socket, I thought it would be best if I could find a rock with a dimple in it.  I visited the landscape beds around the Sonic a block away from my house to search for a river rock with just the right dimple in it.  While the one I found is not totally ideal, it has served me pretty well so far.  I’m sure it has contributed to the shortened longevity of the spindle by sanding off material, but all-in-all, it has served me well.

It took me an afternoon to make the bow, spindle and fireboard.  I spent the next few days, looking for a suitable rock for the socket.  By the third day, I was ready to try to make fire.

From what I had read about using a bow-drill, I understood that how you hold and use it is as important as the materials themselves.   I knew that I needed to brace the socket hand against my shin, and that I needed to keep my right leg behind my left leg in order to open up the right side of my body for the bow action.  Other than that, it seemed like it was mostly a matter of making friction.

My first try didn’t go to well.  I got lots of powder coming out of the chimney notch, but I could tell that it wasn’t very consistent.  It started out as really light brown (from pressing to lightly on the socket) and then turned fluffy black (just right) and then turned into black flakes (from pressing to hard).  But by the time I had gotten to that point, my body was tired.

I spent the next day or two, conversing with experts on the Rewild.Info forum.  I got lots of good advice from Scouts of both the Urban and Penny varieties.  Urban Scout shared with me his explanation of the perfect form.  This info is on the Rewild.Info wiki article, but I’ll also outline it here for your convenience.

  1. Put the fire board under your left foot. Align it so its next to your ankle (so that the board appears to be sticking out to your right, from your ankle.
  2. Straighten your shins and thighs into a box shape… Make your legs right angles at your knees. Your right shin should be flat on the ground, pointing behind you. Your right thigh should come up straight, making the back side of the box/square. Your left thigh should stick out straight making the top of the box, then your left shin should go straight down to the ground making the front side of the box, then the ground between your left foot and right knee makes the bottom. The distance between your left foot and right knee should match the length of your left thigh, making it square looking.
  3. Wrap the spindle in the bow. Put your hand hold in your left hand, wrap your left arm around your left knee and angle your fist inward toward your body. Notice that a notch-shape appears where your wrist and hand/thumb meet. That notch or crook in your hand/wrist should fit nicely into your left shin. Since you placed you fire board, and lined up your socket near your ankle, you can use this notch in your hand/wrist to “hook” into your shin for total support. This helps mostly to keep the spindle straight up and down and in place. It also allows you to use your body weight for pressure instead of your arm strength.
  4. Hold the bow from the very back.
  5. As you begin drilling, keep your bow arm straight and let it swing like a pendulum.
  6. When first drilling, you want to go faster and harder to get a base of powder, as your powder builds, you can use longer, slower strides. You’ll hear the rhythm of it when you’ve got it going. It just makes this perfect sawing sound.
  7. If your string slides around your bow as you drill, tighten your string. If your spindle keeps popping out every time you let off pressure, loosen the string. If your spindle is wound to tight, the only way to get it to turn is with lots of downward pressure, which is generally too much. Loosen the string, see what happens.

I spent the next night trying out all the tips I’d learned.  On my first try, I was able to get a really tiny coal, but in my excitement, I over-fed it, and it blew out before it could really grow.  Fueled with the encouragement that I must be doing something right, I set at it again.

This time, there was a lot of good-looking powder and a lot of healthy smoke pouring from the friction surfaces.  I didn’t know how long it would take to get a really good coal going, but I figured it would be better to over do it than under do it.  I kept up my sawing motion with the bow.  My arm got very tired, and the string started slipping around the spindle. I tweaked the string as best as I could to keep the spindle spinning and the smoke pouring out.  Finally, I couldn’t take it any longer, and I gave up.

When I pulled the fireboard off the little piece of bark I was using to catch the coal, it looked like there was nothing there.  I cursed.  All that effort, and no coal.  But then I saw the tiniest wisp of smoke coming from the pile of powder.  I gently fanned it and saw the pile glow red from the inside.  I was amazed, the coal was inside the pile.  I started fanning it more with my hand, and eventually, the coal burned its way through to the top of the pile.  By this time, it was really big and really healthy.

I still had the tinder bundle I had made from my first attempt.  I had shoved it in a flower pot by my front door to keep the wind from scattering it about my yard.  It was a nest of dried grass, stuffed with cattail down.  I gently tapped the coal off the piece of bark into the cattail and then began to blow.  I cupped the bundle in my hands in front of my face and blew into it and held it up with the wind at my back to let it help me feed air to the coal.

The cattail down began to smoulder with a feverish intensity.  I could see how the flower can be used as a punk.  The little fluffy strands burned as intently as a coal themselves.  And then, all of the sudden, the grass caught flame.  I shrieked for joy.

I wasn’t interested in starting a campfire, but if I had been, this would have been the moment to set the flaming tinder next to my already prepared kindling and let the flames spread through the waiting wood.

Instead, in celebration, I lit a cigarette off of the flame and drank the fruit of the fire into my lungs.

I felt triumphant.  I felt like I had learned a secret about how to really live.

I have since been able to bust quite a few coals myself.  Some of them I have even been able to blow into flame.  I also helped my friend Luke use the set to produce coals and his own first fire.  I intend to spread the gospel of friction flame to anyone who will listen.  Part of that message will include these words of wisdom that Urban Scout shared with me concerning the mystery of fire:

According to Martin Prechtel, the gods of fire hid their wisdom where no one would find it–in the water. He says this is why willow is so great for making fires.

Now it’s your turn, gentle reader.  Go spread the flame.


7 responses to this post.

  1. Thank you for sharing your story.


  2. Shit, thanks for all the help, Scout! It would have been a hell of a lot harder, without you.


  3. Great story. I still remember the first time I got a coal. It was one of the best feelings I’ve ever had. I still feel awed everytime I get one. I still have trouble getting one with different sets. There is never a time to stop learning.

    I’ve challenged myself with some harder skills like making a set with only stone tools. I ended up finishing the notch with a knife and I didn’t use natural cordage. The lesson was how valuable knives are.

    I also practiced getting a coal with the opposite arm. This isn’t too hard actually if you concentrate.

    Getting a coal in the dark. I haven’t tried blindfolded yet.

    My thought process for bow movement is:
    1. Slow and smooth to warm up the fireboard
    2. Heavy downward pressure to build up the dust
    3. Let up on the pressure and up the speed as fast as controllable to ignite.

    I generally go until smoke is wafting heavily for 10+ seconds because I don’t like to have to start over. I always try to take as long as strokes as possible using the whole bow.

    I’ve yet to use any handhold other than wood. I think as long as the handhold is as hard or harder than the spindle you are ok. Of course you have to lubricate it with something after you burn in the initial hole. I use dry soap usually.


  4. Posted by Rix on 03/29/2007 at 2:35 pm

    Thanks, Sassmouth, for the great advice on bow movement. I also try to keep going after I get some good smoke going for the same reason (hate to start over).

    I’d like to do some experimenting–maybe use primitive tools. But I’d really like to figure out ways to drop the energy input–like burning a new hole next to an old hole so that i can cut a notch between the two with the grain instead of against it. Or by tying two spindle-sized limbs together and using the natural crack between them for letting the coal form.

    But right now I’m just having fun practicing what I just learned.


  5. […] only is it fun to research articles to put on the wiki field guide (my bow-drill experiment began with and was inspired by the research I did for the REWILD bow-drill article) but it also […]


  6. Posted by alexander on 06/16/2007 at 4:18 pm

    Making fire with a bow drill is one of the handest and best thing i have ever done in my life, see guys who are reading this has it change your life, dont worry if you dont pick it up the first time it took me along time to learn so never give up on it. and remember its all in the mind. just think when your around men who think they are ‘real men’ just remember you can make fire!


  7. Mo-ji-to

    A few years ago, I tried a mojito for the first time at this little burrito chain on the Upper East Side in NYC called Blockheads.  They decorate with sock monkeys.  It sounds strange, I know.  What do sock monkeys have to do with burritos–or …


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