Bow drill
Overview
 
The bow drill is an ancient tool
Tool
A tool is a device that can be used to produce an item or achieve a task, but that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such...

. While it was usually used to make fire
Fire
Fire is the rapid oxidation of a material in the chemical process of combustion, releasing heat, light, and various reaction products. Slower oxidative processes like rusting or digestion are not included by this definition....

, it was also used for primitive woodworking
Woodworking
Woodworking is the process of building, making or carving something using wood.-History:Along with stone, mud, and animal parts, wood was one of the first materials worked by early humans. Microwear analysis of the Mousterian stone tools used by the Neanderthals show that many were used to work wood...

 and dentistry
Dentistry
Dentistry is the branch of medicine that is involved in the study, diagnosis, prevention, and treatment of diseases, disorders and conditions of the oral cavity, maxillofacial area and the adjacent and associated structures and their impact on the human body. Dentistry is widely considered...

. It consists of a bearing block or handhold, a spindle or drill, a hearth or fireboard, and a simple bow. Related drills include the pump drill and the hand drill.
The bow drill appeared in Mehrgarh
Mehrgarh
Mehrgarh , one of the most important Neolithic sites in archaeology, lies on the "Kachi plain" of Balochistan, Pakistan...

 between the 4th and 5th millennium BCE.
Encyclopedia
The bow drill is an ancient tool
Tool
A tool is a device that can be used to produce an item or achieve a task, but that is not consumed in the process. Informally the word is also used to describe a procedure or process with a specific purpose. Tools that are used in particular fields or activities may have different designations such...

. While it was usually used to make fire
Fire
Fire is the rapid oxidation of a material in the chemical process of combustion, releasing heat, light, and various reaction products. Slower oxidative processes like rusting or digestion are not included by this definition....

, it was also used for primitive woodworking
Woodworking
Woodworking is the process of building, making or carving something using wood.-History:Along with stone, mud, and animal parts, wood was one of the first materials worked by early humans. Microwear analysis of the Mousterian stone tools used by the Neanderthals show that many were used to work wood...

 and dentistry
Dentistry
Dentistry is the branch of medicine that is involved in the study, diagnosis, prevention, and treatment of diseases, disorders and conditions of the oral cavity, maxillofacial area and the adjacent and associated structures and their impact on the human body. Dentistry is widely considered...

. It consists of a bearing block or handhold, a spindle or drill, a hearth or fireboard, and a simple bow. Related drills include the pump drill and the hand drill.

History

The bow drill appeared in Mehrgarh
Mehrgarh
Mehrgarh , one of the most important Neolithic sites in archaeology, lies on the "Kachi plain" of Balochistan, Pakistan...

 between the 4th and 5th millennium BCE. This bow drill—used to drill holes into lapis lazuli
Lapis lazuli
Lapis lazuli is a relatively rare semi-precious stone that has been prized since antiquity for its intense blue color....

 and cornelian
Carnelian
Carnelian is a brownish-red mineral which is commonly used as a semi-precious gemstone. Similar to carnelian is sard, which is generally harder and darker...

—was made of green jasper
Jasper
Jasper, a form of chalcedony, is an opaque, impure variety of silica, usually red, yellow, brown or green in color; and rarely blue. This mineral breaks with a smooth surface, and is used for ornamentation or as a gemstone. It can be highly polished and is used for vases, seals, and at one time for...

. Similar drills were found in other parts of the Indus Valley Civilization
Indus Valley Civilization
The Indus Valley Civilization was a Bronze Age civilization that was located in the northwestern region of the Indian subcontinent, consisting of what is now mainly modern-day Pakistan and northwest India...

 and Iran
Iran
Iran , officially the Islamic Republic of Iran , is a country in Southern and Western Asia. The name "Iran" has been in use natively since the Sassanian era and came into use internationally in 1935, before which the country was known to the Western world as Persia...

 one millennium later.

Description

This is an ancient method of starting fire without matches or a lighter. It uses friction to generate heat. The heat eventually produces an ember in the burnt sawdust. The ember is tiny, smaller than the head of a cigarette, and fragile. Once the ember is formed it is carefully placed into a "tinder bundle" (a bird's type nest of stringy, fluffy, and combustible material). Once the ember is in the tinder bundle it is then carefully nurtured and coaxed into flame. Once the tinder bundle bursts into flame, it is then placed into the fire lay.

The spindle, carved to reduce friction at one end and maximize it at the other, is held in a hole in the bottom of the bearing block, and at the other by the hearth(fireboard). The string of the bow is wrapped once around it, so that it is taut enough not to slip during operation. A variation on this called the "Egyptian Bow Drill" which attaches the string by wrapping it around multiple times, or actually tying it to the drill or through a hole through the drill shaft, then wrapping it.
("Egyptian Bow Drill" from link on main fire making article)

The usual position that a person assumes whilst operating the bow drill is as follows: the right knee is placed on the ground (assuming a right-handed operator) and the arch of the left foot is on the board, pinning it in place. The left wrist, holding the handhold, is hooked around the left shin and locked in place to keep it steady so it can generate enough downward pressure
Pressure
Pressure is the force per unit area applied in a direction perpendicular to the surface of an object. Gauge pressure is the pressure relative to the local atmospheric or ambient pressure.- Definition :...

 and speed
Speed
In kinematics, the speed of an object is the magnitude of its velocity ; it is thus a scalar quantity. The average speed of an object in an interval of time is the distance traveled by the object divided by the duration of the interval; the instantaneous speed is the limit of the average speed as...

; achieved by pushing down with the handhold and spinning the drill. The heat of the friction between the hearth and the spindle both creates charred, fuzzy dust and causes it to ignite - forming a coal or ember. The handhold is lubricated
Lubricant
A lubricant is a substance introduced to reduce friction between moving surfaces. It may also have the function of transporting foreign particles and of distributing heat...

 and the spindle is carved to about thumb
Thumb
The thumb is the first digit of the hand. When a person is standing in the medical anatomical position , the thumb is the lateral-most digit...

 thickness, usually 6 to 8 in (15.2 to 20.3 ) long. Another option to practice is to make the "handhold" into a "mouth-hold" piece, so it's held down by pressure from the chin/mouth, leaving both hands free.

An indentation and a "v" notch into the center of the dent is made into the fireboard and the spindle is placed on it. The notch allows a place for the dust collect while it is being abraded off the spindle and the hearth. Eventually, the friction generates heat
Heat
In physics and thermodynamics, heat is energy transferred from one body, region, or thermodynamic system to another due to thermal contact or thermal radiation when the systems are at different temperatures. It is often described as one of the fundamental processes of energy transfer between...

 to ignite the dust, which can be used to light tinder
Tinder
Tinder is easily combustible material used to ignite fires by rudimentary methods. A small fire consisting of tinder is then used to ignite kindling. Anything that can be ignited by a match can be considered tinder; or by more rigorous definition, anything that begins to glow under a shower of...

.
Whilst a "v" is most common, other methods to create a cavity to contain the dust whilst it is being ignited can be used. For example, drilling part-way into a hearth made by lashing two sticks together from one side, and then drilling from the other side to meet this hole; or using the area where two branches separate. This is to keep the coal off wet or snow covered ground.

The hearth and spindle can both be medium-soft woods and work best when both are made from the same wood, however with practice almost any wood can be used. The most important factor is weather the wood is dry enough to ignite, wet wood will not work; yucca
Yucca
Yucca is a genus of perennial shrubs and trees in the family Asparagaceae, subfamily Agavoideae. Its 40-50 species are notable for their rosettes of evergreen, tough, sword-shaped leaves and large terminal panicles of white or whitish flowers. They are native to the hot and dry parts of North...

, aspen
Aspen
Populus section Populus, of the Populus genus, includes the aspen trees and the white poplar Populus alba. The five typical aspens are all native to cold regions with cool summers, in the north of the Northern Hemisphere, extending south at high altitudes in the mountains. The White Poplar, by...

, white cedar, basswood, and most willow
Willow
Willows, sallows, and osiers form the genus Salix, around 400 species of deciduous trees and shrubs, found primarily on moist soils in cold and temperate regions of the Northern Hemisphere...

s all work very well. Combinations such as hazel
Hazel
The hazels are a genus of deciduous trees and large shrubs native to the temperate northern hemisphere. The genus is usually placed in the birch family Betulaceae, though some botanists split the hazels into a separate family Corylaceae.They have simple, rounded leaves with double-serrate margins...

 and poplar also work well. The bow should be stiff but slightly limber and around the distance from the users armpit to their fingertips. The bearing block (handhold) can be made of anything that is harder than the spindle. Bone
Bone
Bones are rigid organs that constitute part of the endoskeleton of vertebrates. They support, and protect the various organs of the body, produce red and white blood cells and store minerals. Bone tissue is a type of dense connective tissue...

, antler
Antler
Antlers are the usually large, branching bony appendages on the heads of most deer species.-Etymology:Antler originally meant the lowest tine, the "brow tine"...

, and stone
Rock (geology)
In geology, rock or stone is a naturally occurring solid aggregate of minerals and/or mineraloids.The Earth's outer solid layer, the lithosphere, is made of rock. In general rocks are of three types, namely, igneous, sedimentary, and metamorphic...

 work best, as they can be easily greased, do not create as much friction, and do not burn; however, hard woods such as maple
Maple
Acer is a genus of trees or shrubs commonly known as maple.Maples are variously classified in a family of their own, the Aceraceae, or together with the Hippocastanaceae included in the family Sapindaceae. Modern classifications, including the Angiosperm Phylogeny Group system, favour inclusion in...

 and tulip
Liriodendron
Liriodendron is a genus of two species of characteristically large deciduous trees in the magnolia family .These trees are widely known by the common name tulip tree or tuliptree for their large flowers superficially resembling tulips, but are closely related to magnolias rather than lilies, the...

 and red cedar
Red Cedar
- Trees :* Toona ciliata, an Australian / Asian rainforest tree* Juniperus virginiana, a North American juniper* Thuja plicata, a North American tree in the cypress family- Places :Canada* Red Cedar Lake , a lake in the Temagami region...

 are quite serviceable and often easier to find and work.

This is by far the easiest method of producing a coal by primitive means and anyone can do it by using good materials and maintaining a calm mentality, concentrating only on working everything slowly and smoothly.

Pump drill

A pump drill is a simple tool used to make holes in light materials by hand and has been in use for centuries. The drill itself is composed of: the drill shaft, a narrow board with a hole through the center, a weight (usually a heavy disc) acting as a fly wheel, and a length of cord
Cord
Cord may refer to:* String or rope* Cord , a trimming made of multiple strands of yarn twisted together* The spinal cord* Cord Automobile, a former American car marque founded by Errett Lobban Cord* The cord , used to measure firewood...

. The weight is attached near the bottom of the shaft and the hole board is slipped over the top. The cordage is run through a hole near the top of the shaft and affixed to either end of the hole board so that it hangs just above the weight. The end of the shaft usually has a square hole made to fit certain sized auger
Auger
An auger is a drilling device, or drill bit, that usually includes a rotating helical screw blade called a "flighting" to act as a screw conveyor to remove the drilled out material...

 bits or a simple triangular bit made to cut while rotating in both directions.

To use one hand is placed on the hole board while the other turns the shaft to wind the cord around its length thus raising the hole board to near the top where the cord becomes taut. Placing the tip against the material to be drilled and held upright, a smooth downward pressure is exerted on the board causing the drill to rapidly spin. Once the bottom is reached, the weight is relieved and the drill allowed to rebound re-winding the cord around the shaft and the process is repeated. It is a skill simple in concept but takes some practice to master and greatly speeds up the process of making small holes.

Hand drill

The hand drill is a similar method, but uses a longer, thinner spindle; and instead of a bearing block and bow combination, the downward pressure and spinning is achieved by rubbing the hands together around the spindle. As the hands move downward to the base, where the drill is pinched and the hands are brought quickly to the top one at a time. This can be made unnecessary by cutting a nock at the top of the drill, tying a cord through this, and then putting your thumbs through loops in the cord. However, skilled operators can either maintain pressure with their hands almost stationary vertically; or, in a movement comparable to floating
Floating (dance)
Floating, gliding or sliding refers to a group of footwork-oriented dance techniques and styles closely related to popping, which attempt to create the illusion that the dancer's body is floating smoothly across the floor or that the legs are walking while the body travels in unexpected directions....

, can "float" their hands back to the top of the drill. There is a more limited choice of materials to use with this method, needing much softer materials, such as mullien, yucca, cattail, and root wood.

External links

The source of this article is wikipedia, the free encyclopedia.  The text of this article is licensed under the GFDL.
 
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