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ORNAMENTAL OBSESSIONS Jon Magill will be a demonstrator at the 2016 AAW international symposium in Atlanta, Georgia, June 9-12, 2016. For WHAT IS OLD IS more, visit woodturner.org. NEW AGAIN A History of Contemporary Ornamental Turning Jon Magill here seem to be two types of of the lathes used, how the workpiece people, those who look at some- is manipulated, and the cutters that T thing and say, “That’s pretty,” are employed. Those constitute the and those who ask, “How did they root of OT and the nearly infinite pat- do that?” Most woodturners, myself terns that are possible, once mastered. included, seem to fall into the latter category. That explains in a nutshell What is OT? how I became fascinated with the rela- OT is all about geometry, the enablers tively obscure realm of ornamental of that geometry being the specialized turning, or OT for short. lathes, the ingenious chucks, and the OT is a specialized subcategory of multitude of various cutters. Starting woodturning, much the way seg- with the lathes, we encounter the first mented turning can be thought of. major division of the OT realm into its Generally speaking, OT is a collection two main subcategories: index work of techniques used to add decoration, and engine turning. or “ornamentation,” to turned objects. As its name implies, index work is In some senses, it might be considered carried out when the spindle on the geometric carving that is typically lathe is indexed to a new fixed posi- accomplished with a rotating cutter of tion, using an indexing wheel and a some sort. The departure from normal pin detent. Once the spindle is posi- Turned Ivory woodturning techniques becomes tioned, a cut is made, then the lathe by Johann obvious when we look at the specifics is indexed again to another position Eisenberg, 1624, 16¼" (41cm) tall Photo by Jon Magill, Journey into ornamental turning JOURNAL ARCHIVE CONNECTION Antique eccentric chuck mounted on lathe spindle printed with permission, and set to about 1" of eccentricity. Ornamental Museo degli Argenti, Jon Magill has written extensively for American Rose-Engine Florence, Italy Primer on OT cutting tools Obsessions Turning Slightly Eccentric By Jon Magill Jon Magill Woodturner on ornamental turning. His past rnamental turning—OT any woodturners, when fixed or is rotating very slowly, at Instead of admiring among its fans—is looking at ornamental usually less than 10 RPM. ornamental turning, The Cutting turning (OT) work, will Given these two variables, histori- Oadmired by many but M practiced by few. One of the it’s time you give it a ponder, “How did they do cal ornamental turners, inventors, and obstacles that holds turners back is try. Here is an easy that?” The answer often lies toolmakers went to great lengths that this intriguing work requires in the myriad of specialized to devise some of the most esoteric a rare specialty lathe. and inexpensive way equipment that has been pieces of apparatus ever conceived, At least it was rare until now. to start, including invented and perfected over simply to decorate various surfaces of articles are referenced more specifically EdgeBy Jon Magillof OT All the projects shown on the the centuries. a workpiece. There were two options following pages were turned on a details on how to When studying OT pieces, one for gadgets that preoccupied most of homemade rose-engine lathe. Not build your own rose- must be aware of the two main dif- the OT inventors: devising new cutters rnamental turning—OT full understanding of OT, we’ll leave only is it easy to build, it’s capable ferences between OT and regular to cut in a different way, and inventing engine lathe. as it’s known in some those for a future article. of doing precision OT work. woodturning. First, the cutting in OT new chucks that would allow orienting turning circles—is For now, let’s regress a step The four projects that follow O is done with a rotating cutter that is the workpiece in some specific way. a broad and interesting, and take a closer look at provide an introduction to the headstock is not stationary. generally spinning at a few thousand In the Spring 2008 issue of American but specialized, niche of the OT tool’s role and the throughout this article. AAW members can the rose-engine lathe and its Instead, the headstock is hinged, RPM. Second, the workpiece on an Woodturner (AW vol 23, no 1), I briefly woodturning. Journal broad range of OT cutting capabilities plus an overview of allowing it to pivot back and forth, ornamental lathe, depending on the explored the range of cutting frames— articles (see the Spring implements. After all, some basic techniques. called rocking. By controlling this kind of work being done, is either the rotating tools in their various 2007 issue) and subsequent this is where the whole Of course, you’ll first have to rocking motion with a rubber incarnations—that allow cutting in a symposium demos have story begins. build your lathe, described on page riding against a rosette—a similar to router speeds—and variety of orientations and patterns. aroused considerable Because the major- 52. A dozen AAW members have cam-like disk—you can cut taking light cuts on each pass. These cutting frames are presented to interest in OT. (Detail below) Theity adjusting of the workknob done already made these lathes, and you countless patterns. For more help with terminology, see the work at different angles, and often Last year’s goal of the at the top of the chuckon a hasrose a enginesmall uses can do this too! Another distinction is that, the photos opposite and on page 52. scale for fine adjustments. with profiled cutters in an assort- access these and all past journal articles online Ornamental Turners Interna- only one cutter style, Much of what is described in unlike regular turning, rose- To see a video clip of a rose engine in ment of shapes, to produce a countless tional (an AAW chapter) was the previous rose-engine these pages will be obvious the first engine turning is usually done action and for more OT history, visit number of potential patterns. simply to expose more AAW article oversimplified some time you turn the crank on your with a motor-driven fly cutter, the AAW website at woodturner.org. Any well-equipped OT setup, or members to this style of turning of the details for tooling rose engine. But until you actually known as a cutting frame. By “kit” as the British refer to it, would with a gallery of works, a project- (cutters and cutting frames). see it happen, text descriptions hand-cranking the lathe, the turner Get started consist of many different chucks. A centric article, and a hint of the range The typical tool used on a rose cannot do it justice. The magic of rotates the piece slowly past the When first becoming familiar with dizzying array of ingenious chucks of what can be accomplished with OT. engine has a tip sharpened to a 60- how a rose engine works and what cutter. The most common cutting your rose engine, you may want This ornamental turning sample shows has been invented to enable decora- Armed with information on building just two variations of the thousands degree angle and held in one orien- at woodturner.org. it does is something that has to be frame, a horizontal cutting frame, to devise some sort of a paper possible on the basket-weave pattern. tion on any surface of a workpiece. By a rose-engine lathe, many members tation. As a result, the more involved(Detail above) The eccentricity experienced. is a tool supported on some sort of chuck, as shown in Photo 1, which The left is a simple alternating pattern; using these chucks, the woodturner have now started down the path of the right a pseudo-spiral effect. The discussion of various cutters and scale is engraved on the back at A rose engine differs from slide rest, which has a fly cutter is useful for drawing the patterns face and the right end show two types the bottom of the chuck. Two holes can position the workpiece relative OT enjoyment. cutting frames was glossed over dueallow a tapered pin to be inserted, other lathes in many ways, but rotating in a horizontal plane. The and helping understand what the of circular cuts possible with the eccen- to the spindle-axis of the lathe. Most Because learning ornamental tric cutting frame (ECF). The cut on the to space limitations. locking the eccentric chuck in its the biggest difference is that cutter is spinning at high speeds— rosette, shown in Photo 2, will centered position. of these chucks appear ungainly or turning is like learning to turn from side of the cylinder has been “beaded” OT differs from regular wood- first with the ECF, then decorated on the beginning, now seems like a the resulting curved surface with turning in that most of the work is good time to cover some OT basics. additional circular patterns. done with a rotary cutter introduced 46 American Woodturner Spring 2007 60 American Woodturner Fall 2009 The majority of what is accom- to the workpiece, which is either sta- plished in OT is attributable to the Over the centuries a dizzying and tionary, indexed to a specific spindle specialized cutting implements and ingenious array of chucks have been position, or slowly revolving. ingenious chucks. The cutters (plain invented that allow the position- OT is all about: 1) precisely position- and profiled) produce endless ing, orientation, and movement of ing, orienting, and moving the cutter; patterns.

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