Fire Plough & Fire Saw: Friction Fire Methods Beyond the Drill

Fire plough and fire saw: where they sit among friction fire methods

Every friction fire works the same way: two pieces of dry wood rub against each other, the friction grinds them into fine dust and heats it, and when enough hot dust gathers in one insulated pile it starts to smoulder on its own. That smouldering pile is the ember. What differs between the methods is how the wood moves.

• Drills spin a spindle in a socket: the bow drill with a bow and cord, the hand drill between your palms.
• The fire plough pushes a stick back and forth along the grain of a board, in a groove. Dust is shoved forward and heaps at the end of the groove.
• The fire saw rubs an edge across a slit in a split piece of bamboo or wood. Dust falls through the slit onto tinder underneath.
• The fire thong pulls a strip of cane or cord back and forth under a split stick, a variation of the same idea.

Why learn them at all?

The fire plough needs no cord and no carved socket, only a board, a stick and a knife. It shows you very clearly how pressure, speed and dust work together, because you can watch the groove darken and the pile grow stroke by stroke. The fire saw is the classic method in regions where large bamboo grows. For most people in Europe, though, both are skills to practise and enjoy, not methods to rely on. If you have never made a friction ember, start with the bow drill: it teaches what good dust and a real coal look like with far more margin for error.

How does a fire plough work?

A fire plough has only two parts: a hearth board with a straight groove on its top face, and a plough stick with a blunt, wedge-shaped tip that fits the groove. You hold the stick with both hands at a low angle, press its tip into the groove and push it forward and back along the groove, faster and faster.

Three things happen at once:

• The groove grinds dust. Under pressure the tip and the groove floor wear each other down into fine wood dust.
• The friction heats it. Fast, firm strokes make heat faster than it can escape into the board and the air.
• The dust collects in one pile. Each forward stroke shoves dust towards the far end of the groove, where it heaps up. A deep enough, hot enough pile insulates itself and begins to smoulder.

The pile at the end of the groove plays the role of the notch in a drill hearth: it is where the dust is kept together and where the coal is born. If the dust is scattered along the board or blown away, there is no ember, however hard you push.

The stick angle

Hold the stick at a low angle to the board, roughly 30–45° as a rule of thumb. Lower, and the tip skids out of the groove and your pressure goes forward instead of down. Steeper, and the tip digs in and stalls, and the strokes get short. Within that range, find the angle at which you can press hard and still push smoothly.

The best wood for a fire plough and fire saw in Europe

The rules are the same as for the drills: dead, bone-dry, non-resinous wood of soft to medium hardness. The plough is even less forgiving of damp wood than the bow drill, because each stroke spreads its heat along the whole groove instead of concentrating it in one socket.

Hearth board

The proven European choices are lime (linden), willow, poplar and aspen, the same woods recommended in the bow drill wood guide and the tree identification guide. Dead alder and thick dead ivy stems are also used. In North America, basswood, cottonwood and cedar fill the same role.

Plough stick

The stick is often made of the same wood as the board, or of a slightly harder wood so that the groove wears more than the tip. Straight, dead, dry hazel shoots are a good choice in Europe; dry dead elder also works, though it is not suitable for food contact. What matters most is that the stick is dry, straight enough to hold comfortably and not resinous.

The thumbnail test and the dry test

Press your thumbnail firmly into the board: a clear dent means the hardness is right, no mark means too hard, and crumbling means rotten. Then check dryness. Dead wood that lies on the ground soaks up moisture; standing dead wood, dead branches still on the tree, is usually much drier. If the outside is damp, split the piece and work from the dry core; see batoning.

Making a fire plough: board, groove and stick

A sharp knife is enough; a small saw and an axe or batoning make splitting the board easier. If you are new to knife work, practise the carving basics first, choose a sturdy bushcraft knife, and check the knife laws where you live before carrying one.

These are rules of thumb, not exact measurements. Adapt them to your wood and your body.

The board

Split a dry dead branch or small log in half and carve the split face flat, so the board lies steady without rocking. Leave the round side down. Choose a piece without knots along the line where the groove will run, because a knot stops the stick and hardens the groove.

The stick tip

Carve the tip into a blunt wedge, rounded at the very end, about as wide as the groove you want. A sharp point digs in and stalls; a flat, square end skids. The tip wears into the shape of the groove during the first strokes anyway.

Fire plough technique: body position, strokes and pacing

Body position

• Lay the board on dry ground or on a layer of dry bark, groove up. In damp conditions, put a few dry sticks under it.
• Kneel behind the near end of the board, so the groove runs away from you. Some people sit astride the board or brace its near end against their knees; what matters is that the board does not slide.
• Hold the stick with both hands, one above the other, and lean your upper body over it. The pressure should come from your body weight, not only from your arms.
• Keep your back as straight as you can and your elbows slightly bent. Locked arms tire fast and make the strokes jerky.

Pacing: long strokes, then speed up

The plough rewards patience at the start and all-out effort at the end. Begin with long, even strokes over the whole groove to heat and dry the wood and to build up a pile of dust. Then, as smoke rises, shorten the strokes slightly, speed up and press harder, always ending each forward stroke at the dust pile.

Breathing and rests

Breathe out on the push and in on the return. Holding your breath tires you within seconds. The final burst is short and very hard; if you run out of strength before the pile smokes on its own, stop, rest a few minutes, and start again with a few warming strokes before the next burst. Repeated all-out attempts make you sweat, which chills you afterwards, so budget your energy.

The fire saw: split bamboo, split sticks and the cross-groove

The fire saw turns the plough around: instead of pushing along the grain, you rub an edge across the hearth. The classic hearth is a length of dry bamboo split in half. A narrow slit is cut across the convex side, right through the wall, and fine tinder is placed under or inside the hollow below the slit. A second piece with a blunt, bevelled edge is then sawn back and forth across the slit. The friction cuts a cross-groove, and the hot dust falls through the slit onto the tinder, where it can form an ember directly.

Bamboo in Central Europe: be honest

The fire saw is traditional where large bamboo grows naturally, in parts of South and South-East Asia, for example. In Central Europe, suitable bamboo is rare: garden bamboo is usually green, thin or protected as someone's property, and dry, thick-walled pieces are not something you will find in a forest. Bamboo sold as garden or craft material can be used for practice at home if it is completely dry, but you cannot count on it outdoors.

Split softwood alternatives

Without bamboo, a fire saw can be made from dry split wood: a dead lime, willow or poplar stick split in half, with the slit cut across the round side. Soft wood here means soft, non-resinous broadleaf wood, not resinous conifers. The saw piece can be a split board of the same wood or of hazel, with one edge carved to a blunt bevel. Expect it to be harder than with bamboo: the solid hearth needs a deeper cut before the dust can fall through, so many people cut the slit most of the way through first and place the tinder or an ember pan directly under it.

The fire thong in brief

The fire thong is a relative of the fire saw. A split stick lies on the ground, held down by your foot, with a little tinder or an ember pan under a slit. A strong, flexible strip, traditionally split rattan or cane, is passed under the stick and pulled up and down alternately with both hands, like a shoeshine cloth. The friction cuts a groove into the stick, and the dust falls through onto the tinder.

In Europe the fire thong is mostly a curiosity. Rattan is not a native plant, and most improvised strips of bark or natural cordage wear through or snap before an ember forms. Paracord tends to melt and glaze. If you want to try it, use a dry split lime or willow stick and a strip that is tough and dry, and treat it as an experiment rather than a method.

Ember care: from the dust pile to the tinder bundle

Prepare everything before you start ploughing: a dry tinder bundle about two fists in size, with a hollow in the middle, made of dry grass, shredded inner bark or other natural tinder; see how to build a tinder bundle. Have kindling such as feather sticks and a ready-built fire lay waiting. Once the ember exists, there is no time to collect anything.

An alternative is to hold the open tinder bundle against the end of the board and tip the coal straight into it, or to lift the pile on the flat of a knife blade. Whatever you do, move the board or the support, not the fragile coal with your fingers.

Extending a small ember

A plough ember is often small and loose. A piece of char cloth or charred punk wood placed against it takes the glow and makes it larger and more stable before it goes into the nest. This is optional, but it helps when the tinder is not perfect. The moment the tinder flames, set it under your fire lay and feed thin kindling. The fire lay picker suggests a lay for your weather, and the firewood calculator estimates how much wood to prepare.

Fire plough troubleshooting: polish, no smoke, coarse dust

The board tells you what is wrong. Look at the groove and the dust before you blame your strength.

Polish: the most common problem

A polished groove means the wood is being burnished instead of ground. It happens when you press hard before the groove is worn in, when the wood is resinous or damp, or when the board is too hard. Scrape both the groove and the tip back to fresh wood with the knife. A pinch of fine, dry sand in the groove can break the glaze, but if the board itself is the problem, choose a softer, drier one.

No smoke, or dust too coarse

No smoke at all almost always means damp wood or too little effort; on a humid day the plough may not work at all. Pale, coarse dust like sawdust means the wood is torn: speed up and ease off a little. Rub a pinch of cold dust between your fingers: good dust feels soft, almost greasy, and smears dark, just as described in the bow drill guide.

How hard is the fire plough? An honest look

The fire plough is hard. The final burst asks for a lot of strength and speed for a sustained stretch, and most beginners run out of energy just before the pile starts to smoulder. Expect many sessions before your first ember, even with good wood, and do not judge yourself by video clips of experienced people working with perfect, long-dried boards.

• Practise in dry conditions. A warm, dry summer day with wood that has been dried for weeks gives you the best chance. Fog, rain and damp autumn air make the method far harder.
• Learn the bow drill first. It teaches you what good dust and a real coal look like, with far more margin for error.
• Keep the kit dry. Store board and stick in a dry bag with your bushcraft kit, away from the ground.
• Always carry a backup. A lighter and a ferro rod in separate pockets weigh a few grams and work in seconds; our fire kit guide explains how to put a reliable kit together.

Protecting your hands: blisters and sore palms

The plough is rough on the hands. The stick rubs in your grip hundreds of times, and blisters on the palms and the base of the fingers come quickly, especially in the final burst. The fire saw rubs the same spots on both hands.

• Smooth the stick. Shave off bark, knots and rough spots where your hands hold it.
• Tape hot spots. A strip of athletic or medical tape on the base of the fingers and the heel of the palm helps. Thin work gloves are an option for the plough, because you grip the stick rather than spin it, as long as they do not slip.
• Short sessions. Stop at the first hot spot instead of ploughing into a blister.
• Treat blisters early and watch for splinters from the stick. See blisters and splinters in our first aid guide and carry a basic first aid kit.

Fire safety, fire bans and responsible practice

Fire bans and local rules

An ember is a fire. Rules about open fires differ widely between countries, regions and landowners; many forests, parks and reserves ban fires completely, especially in dry seasons, or allow them only at designated fire places. Ironically, the dry, warm days that suit the fire plough are often the days of high fire danger. Check the current fire danger level and local rules before you practise. This guide is general information, not legal advice.

Knife work and wood

Carve away from your body and keep your free hand behind the blade. Use only dead wood, and ask the landowner before taking any. Do not use unknown plants or wood, and avoid breathing smoke from material you cannot identify. For more fire skills, see our fire skills overview.