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Definition and Brief History of Ornamental Turning
Plain
turning is work executed on a lathe, where a transverse section through any part of the work comprises a
plain circle. Ornamental or Complex turning is executed on a lathe with
attachments which convert that plain circular section to variants of outline;
these range from a simple series of cuts taken at intervals around the
work (so producing grooves or bumps on the surface) to non-circular movements
whereby the whole of the circular shape is removed to give a completely
different form. Such shapes are achieved by various means, the principal ones
being:- - Cutting with a fixed or revolving cutter while the work
is rotated on a non-radial path, e.g.- eccentrically, elliptically,
epicyclically or, following a path determined by a template or reciprocating
device; - Cutting with a revolving cutter while the work remains
static, then partially rotating the work - Cutting with a fixed or revolving cutter while the work
is rotated on a radial or non-radial path and the cutting
apparatus follows a linear, circular or non-circular motion, the two motions
being synchronized by gearing; Ornamental
turning is believed to have originated in Bavaria in the latter part of the 15th
century when it consisted mostly of rose-work, being done by using a cam or
template (called a rosette) mounted on the lathe spindle and allowing the
headstock to rock under tension of a spring or weight, to follow the contour on
the edge of the rosette: also the spindle was allowed to slide to and fro
endwise under tension of another spring to follow the contour on the face of the
rosette. Thus, as the work was
rotated it rocked and traversed so that the cutting tool produced wavy lines
upon the surface. Before the end of the
18th century cutting tools
were generally hand-held or clamped to a fixed 'rest'. The
slide-rest, which allows the cutter to slide along the rest under control of a
screw, although invented c.1480, was not in general use until much later. It is clear from surviving examples of their work that the
skill of the early turners was highly developed. In
response to growing interest by wealthy and great patrons, including several of
the royal families of Europe, two great works on the art and science of turning
were published in France: “L’Art du Tourneur” by Plumier (1701) and
“Manual de Tourner” by Bergeron (1792).
Meanwhile, turning technology was being developed in England where the
practice of arresting the work from point to point (by a division plate) and
applying a revolving cutter (held in an improved slide-rest) was employed.
By the beginning of the 19th century John Jacob Holtzapffel
had established his workshop in London and built a reputation as a maker of
high-class lathes and tools. Many
of his customers were among the monarchs and nobility of Europe and England became the world
centre for the pastime of ornamental turning.
The
Holtzapffel firm continued to make lathes until 1927 by which time they had
produced a total of 2557, serially numbered, many of which were equipped for
ornamental turning. Relatively few of these mechanical marvels survive today and hardly any are complete with all their original accessories. However, the hobby is still kept alive by a small band of enthusiasts, notably the Society of Ornamental Turners, founded in 1948 and based in England but with members world-wide; new groups have since been established, principally in the United States, Australia and New Zealand. The members of these societies seek to develop the knowledge of O.T. and to restore, maintain and use the old equipment or, adapt modern lathes for ornamental turning. Some are even bringing the hobby up-to-date by building computer-controlled O.T. lathes. The
greatest work on ornamental turning is “Turning and Mechanical Manipulation”
by Charles & John Jacob Holtzapffel (5 vols. 1843 - 1897).
Volume 5, entitled “The Principles and Practice of Ornamental or
Complex Turning” is considered to be the ‘bible’ of O.T. but there is much
related information in the other volumes. Other
useful books include: “Ornamental Turning” by J H Evans (1903-4), “The
Lathe & Its Uses” by J Lukin and
“Ornamental Turning” by T D Walshaw (1990).
Reprints of all these books are usually obtainable. The Society of Ornamental Turners was
formed in 1948 with the object to encourage, develop and promote the study and
practice of the art and science of Ornamental Turning.
Its members meet quarterly in London to display examples of their work,
share their experiences and attend a lecture or demonstration.
Seminars and outings to places of interest are also arranged.
A Bulletin containing articles on all aspects of O.T. and news of the
Society is published half-yearly in March and September and a Newsletter in July
and December. The Society maintains a website: http://www.the-sot.com
which contains much information about this pastime, together with a gallery of
pictures of ornamentally turned objects. Competitions are held annually for ornamental turning, plain
turning, making equipment, displays at meetings, contributions to the Bulletin
and for advancing the knowledge of the art. Over many years a close association has been formed with the Worshipful Company of Turners and several members of the Society are Freemen or Liverymen of the Worshipful Company. From time to time the Worshipful Company holds competitions which include categories open to members of the Society. [Written
in 1992 jointly by John F. Edwards (past President of the Society of Ornamental
Turners) and the late Roger Davies (former Editor of the Society) and revised by
J.F.E. 21/04/2010.] (c) copyright notice: The above content is released under the CC-BY-SA 3.0 licence for publication by Wikimedia
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Last modified: April 21, 2010 |
