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The Woodturning Lathe: A Brief History
The lathe is among humanity's oldest and most important machine tools. It can shape, drill, bore and grind. In Turning and Mechanical Manipulation, Vol. I , John Jacob Holtzapffel terms the lathe 'the engine of civilization'. He points out it is unique among machine tools in that not only is it the only machine capable of replicating itself, but it is also capable of manufacturing all other machine tools.
The bow lathe soon gave way to the spring-pole lathe, another type of lathe used by the ancient Egyptians. One end of a rope was fastened to the end of a tree branch, extending downward, making one turn around the workpiece. The lower end of the rope was then tied to a loop that served as a treadle that the turner pressed down with his foot to rotate the work. Although cuts could still only be made while the wood turned in a counterclockwise direction, the pole lathe was a definite improvement over the bow lathe. It afforded a more rapid rotation and the turner now had both hands free to hold the cutting tool.
In 1678 Joseph Moxon extolled the advantages of the wheel-driven lathe in Mechanick Exercises : "Besides the commanding heavy Work about, the Wheel rids Work faster off than the Pole can do; because the springing up of the Pole makes an intermission in running about of the Work; but with the Wheel the Work runs always the same way; so that the Tool need never be off it, unless it be to examine the Work as it is doing." Later versions of the wheel-driven lathe were powered by animals. A mule or horse was hitched to the end of a pole running out from a central shaft on an outdoor device. The animals walked around and around, rotating the main shaft. With a series of heavy gears, the central shaft greatly increased the speed while a smaller shaft brought the power out through a housing on the ground. The housing, connected to another heavy unit, caused a flywheel to spin at high speed. As long as the mules or horses pulled the pole, the pulley operated the device from a drive belt. If more power was required, another animal was added. Other wheel-driven lathes incorporated a water wheel rather than animals. In 1769 Englishman James Watt sparked the Industrial Revolution with his improved version of the steam engine. A few years later, in 1774, another Englishman, John Wilkinson, modified the lathe and patented a precision cannon-boring machine which made efficient steam engines possible. The steam engine cylinder could not be manufactured until machine tools capable of producing accurate parts had been devised; the interior size of the cylinders had to be precise so steam could not leak between the cylinder and piston. Wilkinson's new boring machine provided the accuracy required for the detailed measurements crucial to Watt's design.
The first successful internal combustion engine was patented in 1860 by Jean Joseph Etienne Lenoir of Belgium, and by the turn of the nineteenth century 'oil engines' were manufactured in small units of adequate power to be used in small factories and woodworking shops. As engines improved and became more reliable, compact and affordable, they grew in popularity with individual woodturners with small workshops.
Despite continued advancements in technology throughout the centuries, however, the techniques used to shape the wood remain the same. Consequently, the human elements of skill and talent are still required to create wooden spindles, bowls, vessels, figures, ornaments and other accessories. Bibliography
Primary Sources
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Secondary Sources
:
Francis, Pete. "Bead Revolutions: The Role
of Beads in Technological Change". Lecture. Bead Expo 2000
Symposium, Santa Fe, 26 March 2000.
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The
lathe most likely evolved from the potter's wheel and the bow drill,
which may have been used to bore holes even before fire was discovered.
In fact, fire may have been accidentally discovered by someone trying
to drill a hole in a piece of wood. The presence of stone, shell,
ivory and bone beads with what appear to be drilled holes suggests
that the bow drill may have been used as early as the Late Stone
Age.
The Egyptians are believed to be the first to use lathes, as
evidence of a round tenon joint was found in the tomb of King Tutankhamun
dating back to 1350 B.C. Moreover, the earliest known illustration
of a lathe is a drawing in an Eqyptian tomb dating back to 300 B.C. The drawing depicts one man holding a cutting tool while another
uses a cord to rotate the workpiece back and forth. The Egyptians
also developed the bow lathe which could be operated by one individual.
Two pointed pieces of wood supported the workpiece and a bow with
its string wrapped around the work was used to turn it. The turner
used one hand to move the bow forward and backward, while his foot
and other hand steadied the cutting tool. Cuts could only be made
on one-half of the motion, when the wood was spinning counterclockwise
toward the turner.
Pole lathes continued to be used almost unaltered from about 500
B.C. into the late Middle Ages, until the inefficiency of its reciprocal
action led to the development of wheel-driven lathes. The wheel-driven
lathe provided continuous, controlled rotation in one direction.
This allowed constant cutting, permitting turners to be more precise
and efficient and enabled the use of harder materials. Leonardo
da Vinci was one of many to invent a continuous drive lathe, complete
with treadle, large flywheel, crankshaft, and a tailstock with hand-cranked
screw adjustment. Stuart King explains its operation in his article,
Short History of the Lathe
: "The crank, linked to the
treadle provided constant rotation whilst the momentum of the large
flywheel ensured the crank was carried over its 'dead spot'."
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