Ornamental Turning

Contents

• Introduction, What Is "Ornamental Turning"?
• Reprint of the Holtzapffels' Turning and Mechanical Manipulation

Introduction, What Is "Ornamental Turning"?

NOTE: These are my own opinions, nothing more. For a real definition of Ornamental Turning, find and consult a real ornamental turner.

"Ornamental Turning" is, in my opinion, all that isn't "non-ornamental" turning. This, of course, answers nothing.

To start more simply: A "tool" is something that we use to accomplish some task. While some tools are mental (e.g., the syllogism), the term commonly refers to physical tools (e.g., a hammer). A "machine tool" is a tool of such complexity that it itself has become a machine. The "lathe" is the oldest of the machine tools. It is, in its simplest form, a machine for rotating a workpiece against which is applied a cutting tool. In its simple form, the cutting tool may move to cut various parts of the workpiece, but it does not itself move to produce the cut - the cut is produced by the workpiece moving against the tool. Because of the rotating motion of the workpiece, work at the lathe is termed "turning."

The lathe may be used "freehand," with a hand-held cutting tool. Woodworkers typically still use it in this way, as do technical horologists (cutting metal on a small scale). Formerly, it was used freehand to cut metal on a larger scale.

In engineering applications, the lathe has, for two centuries or more, commonly been used with a mechanically guided tool. In this use, the engineering lathe typically produces simple geometric forms (or their combinations): cylinders parallel to the rotational axis of the lathe, flat surfaces perpendicular to this axis, and to a more limited extent cones (or "tapers").

However "ornamental" the products of either freehand or engineering turning, neither of these is "ornamental turning."

Historically (as documented for example by Moxon in his Mechanick Exercises starting in 1678) lathes were constructed which were capable of more elaborate motions and lathes of all types were used, at times, in more complex manners. As an example of the latter, an ordinary lathe used freehand could be used to turn nested spheres ("Chinese balls"). Moxon also describes lathes which were capable of moving the headstock's spindle left and right along the longitudinal axis of the lathe (under the control of a "swash plate") and lathes which were capable of moving the headstock perpendicular to the axis of the lathe under the control of cams. All three of these methods or mechanisms would be examples of what later became "ornamental" turning.

(There is a small contradiction here in allowing freehand turning, however fancy, into "ornamental turning." It seems to me that when freehand turning produces items which have some mechanical aspect - nested spheres, interlocking spheres, chains, etc. - that it tends to be classed as "ornamental turning," while when it produces solid, if elaborate, figures it is not.)

While fancy freehand turning and swashplate lathes never really became mainstream, lathes which moved the headstock spindle perpendicular to the axis of the lathe did. Under the name of "rose engines," they became quite popular in the 18th century. In satisfying a market of educated, generally wealthy, clients generated by this 18th century enthusiasm for rose engine work, various 19th century makers developed a form of the lathe which, while not usually a "rose engine" or capable of this transverse motion, became characteristic of "ornamental turning."

While such a lathe was fully capable of ordinary turning operations (and might be so used for producing the basic form of a work) it was used more typically as an "indexing" device which allowed the workpiece to be positioned and held stationary at many different angles of rotation. To this lathe, then, an overhead drive apparatus was added which allowed the application of a rotating cutting tool to the workpiece. This allowed the production of elaborate (and highly "ornamental") surface textures. Along with this basic set of mechanisms, such lathes often were equipped with special workholding chucks which could move the workpiece in such a way that elliptical forms were turned (moreover, elliptical chucks could be used to produce rose engine like work).

Soon, an amazing (and this is not simply a superlative - to look at a full O.T. kit in, say, an auction catalog produces a stunning confusion of the mind) array of accessories became available. The Ornamental Lathe became, in the 19th century, a sort of fully mechanical general purpose milling machine capable of producing any form that might be imagined by its especially clever practitioners. In 21st century terms, Ornamental Turning might be seen as "Victorian mechanical analog CNC" (no doubt this phrase will horrify O.T. purists, as perhaps it should!)

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