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A Revolution in Turning Technology Modern tools cut through conventional wisdom, opening up the craft When I began turning in junior high school, using gouges to turn bowls was not an option. It could not be done. Like all novices, I believed this to be sacrosanct and beyond discussion, and for years I scraped my way through bowl blanks. It took a long time and required a lot of sanding to complete a bowl. Most of the tools available were manufactured by Bucks Brothers. They featured short handles on both the spindle gouges and the bowl scrapers, and the steel would not hold an edge. The ceilings above most trade-school lathes had holes or dents in them from flying tools. And then in the early 1970s an Englishman, Peter Child, wrote a book called The Craftsman Woodturner. The major premise was the use of gouges for turning bowls. Child had developed the "Long and Strong Bowl Gouge," and Robert Sorby of England manufactured it. After reading the book, I purchased one of the gouges, and, my, what a difference. What had once taken hours of scraping was reduced to minutes. Here in the United States, as far back as the 1940s, Bob Stocksdale had modified a gouge for bowl turning specifically. To the best of my knowledge, his use of the gouge predates that of any other turner. Conventional tooling and wisdom had been dealt a mortal blow, and the bowl gouge was just the beginning. In the early 1960s, when Stocksdale met Jerry Glaser, an aerospace engineer and hobbyist woodturner, they set out to improve that gouge. The evolution of that tool, the Stocksdale gouge, led to new families of both spindle- and bowl-turning gouges. Many improvements were made to the original bowl gouge. The handle got even longer, giving even greater leverage and control. The wide arc, or flute, at the bottom of the gouge was tightened to reduce its tendency to skate across the wood, and the ears or corner points were ground back to stop them from catching when the tool was angled against the work to produce a planing cut. This became known as a fingernail grind. Also, there was a revolution in tool steel, with high-carbon tool steel -- which took a sharp edge but couldn't hold it for long -- giving way to high-speed steel by the mid-1980s.
Today's bowl gouges are massive tools, with a deep flute ground into a round shaft of high-tech tool steel and long aluminum handles filled with buckshot to dampen vibration. These tools can be guided gently through the wood, slicing it away cleanly and producing a 16-inch bowl from a log in 30 minutes. In the days before this revolution in tool technology, turning a bowl was done with a scraper. Because dried wood was the only wood that would scrape well, one was limited to the species and sizes that lumberyards carried. It is difficult to find dried lumber 6 in. thick and 12 in. wide. Gluing up was one alternative, and many a bowl was composed of different-colored woods of the same or different species. However, if the glue joints were not perfect there was a potential for high-speed delamination. A simple miscue with the tool, and the blank would literally explode. Turning green wood was not a real alternative because a scraper tends to flex thin walls. This meant that the bowl's walls had to be thick, which in turn creates cracking when the wood dries. (For more on using modern bowl gouges to turn green wood and controlling the drying process, see my article "Turning Bowls from Green Wood" in the January/February 2001 issue of Fine Woodworking, #147.) Turning a bowl with a gouge, especially with green wood, is a much simpler, speedier, and safer process. Turning a natural-edged bowl with a scraper is not feasible. The bowl is turned from green wood. Also, there is a real danger of catching the tool since the surfaces are not even or symmetrical. As far as keeping the bark on, well, forget it. The use of a gouge is therefore mandatory. Scrapers Child also developed a set of scraping tools that were used specifically for the grain-transition areas inside and outside the bowl and to smooth out the ridges left by the gouge. These scrapers also were very heavy and long-handled, a radically different design than conventional scrapers. Again, because of the extra mass and longer handles, the tools were much easier to control. However, they were made of high carbon steel at first and dulled rapidly. Later high-speed steel was borrowed from the machine trades and used in many woodworking tools like these scrapers. Spindle gouges In addition to the bowl gouges and scrapers, Child introduced us to a new kind of spindle gouge, with better, thicker steel and longer handles, again with the emphasis of cutting and slicing rather than scraping the spindle. The key to success in spindle- as well as bowl-turning -- using today's gouges -- is to ride the bevel. This is the flat part of the grind that acts like the sole of a plane. If the bevel is ground slightly hollow, on a grinding wheel for example, the bottom of the bevel becomes the pivot point that rides on the surface just cut. Then, small movements up and down with the tool's handle produce much smaller movements at the tool's edge, based on the lever principle. Thus the gouge can be used like a skew chisel, and a fine planing cut can be produced. Also, fine details can be produced with no tearout and no heavy sanding required, which dulls the fine edges of a turned detail. At this point in my career as a bowl turner, I seldom have a need for scrapers, either for transition-grain areas or for final cuts before sanding.
During the same few decades, articulated boring bars, screw chucks, and sharpening devices were developed to fulfill the requirements of a new generation of woodturners. In the 1970s, David Ellsworth began turning hollow vessels. His first tools were scrapers that he had bent with a welding torch. Also in the 1970s, Edward Moulthrop began turning very large hollow vessels, 30 in. in diameter and 36 in. tall. He welded hooks and eyes on very long steel bars, allowing him to turn very large hollow vessels through small entry holes. The development continued, resulting in longer-handled tools with swivel tips that held machinist's tool-steel bits. These offered more control and safety, and could produce a wider variety of hollow-vessel forms. Again Glaser went to work and came up with a double-articulated swivel -- offering a better angle of attack through narrow openings -- and a counterweight attached to the boring bar to dampen the tool's tendency to jerk the wrist. This made turning deep, hollow vessels much easier and safer. When Glaser added longer handles, it was possible to turn hollow vases up to 30 inches deep. Since then, other variations on these long, strong gouges have emerged, making many new forms possible. To see how one of these vessels can be turned in end grain using modern tools, see my article "Turn a Hollow Vessel" in the January/February 2002 issue of Fine Woodworking, #154.
Along with this incredible growth in cutting tools there were tremendous advances in chucks. Three- and four-jaw chucks were adapted from the machine tool trade -- with both self-centering or independent jaws -- and expansion chucks, collet chucks and screw chucks were developed. The self-centering chucks made it easier to mount a piece on the lathe or to return a workpiece to its earlier position. The addition of a fourth jaw to these chucks made holding the work much more secure, and allowed safe offset turning. With these chucks it now is possible to hold and turn a very delicate flower with a thin stem and petals. Slow speeds for large bowls For bowl turners, perhaps the most important development of all was the creation of slow-speed lathes. The early lathes were developed expressly for spindle turning, and speeds began at 1000 rpm. At this speed even a small-diameter bowl can become a lethal projectile. The DC controllers developed in the late 1970s could reduce lathe speeds, but they reduced torque. By the mid-1990s frequency-controlled moters had given the turner both speed control and enough torque to realize just about any design he or she could dream up.
What all of these new tools made possible was the fantastic artistic explosion we see today. Hollow vases, spirals, offset turnings, multi-centered turnings, turnings with bark inclusions and voids in the sides, lidded boxes, translucent flowers, cowboy hats and on and on. Also, because better steel and sharper tools allow cutting with less effort, less sanding, less fatigue and fewer accidents, more and more woodworkers have taken up wood turning.
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