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There are many types of cutting tools that come under the generic category of gouges. These include spindle, bowl, deep-fluted, roughing, and detail gouges. Some will overlap in their functions, as most good tools are prone to do. But all gouges share the common attribute of being cutting tools rather than scraping tools (see illustration on page).

My emphasis on the gouge's bevel angles relates to each tool’s ability to function effectively for the types of cuts you make on bowls and vessels. There’s no question all gouges cut the wood. It’s just that all gouges don’t necessarily work well in all conditions. The traditional gouge, with a 45˚ bevel angle, is extremely efficient, but it is not as versatile as the side-ground gouge at 60˚. Similarly, an 85˚ gouge won’t do what the traditional and side-grind gouges will do, but it will reach those tight areas on the inside of open bowls that the other two gouges won’t.

What is commonly referred to as a traditional or conventional gouge is recognized by its U- or V-shaped flute and where the cutting edge is located—at the intersection of the surfaces of the flute and the bevel. These gouges are primarily used for making spindles, open bowls, and the outside surfaces of bowls and hollow vessels.

Note the U-shaped flute and the cutting edge at the intersection of the flute and bevel surfaces on the traditional gouge. Gouges are cutting tools.

The ⅜" detail gouge is one of the hidden wonders of a woodturner’s armament. I was first introduced to this type of gouge by Rude Osolnik back in the late 1970s, and then later by Michael Mode, whom I met when I moved to Pennsylvania in 1981. I’m sure they both invented it on their own, which is often the case with a good design, as I know neither knew the other at the time. Today, Michael Hosaluk uses a similar tool that is larger in diameter for most of his spindles and bowls.

I created the ⅜"-diameter detail gouge (top) from a ⅜"-diameter spindle gouge (bottom). Note that this has a continuous convex bevel, not a straight-surfaced bevel. There is no sharp trailing shoulder on the bottom of the bevel to compress the fibers while the gouge is cutting.

The photo at right shows a simple 3⁄8"-diameter spindle gouge I have converted into a detail gouge by adding a continuous convex bevel rather than the straight-surfaced bevel you’ll see on traditional gouges. The advantage is there is no sharp trailing edge from the bevel's bottom to compress the fibers as the gouge passes through a cut.

Not unlike the skew, the two planes that form the tip come together at an acute angle—around 10˚ to 15˚—so the edge is predictably very sharp, but not terribly durable.

The secret in using this gouge is to always begin with the bevel against the wood and the tip of the tool in a vertical position when entering the wood. Once the cut is started, roll it to around 10˚ to 30˚ off vertical (axially) as you progress into the cut. You must also always keep the bevel against the wood throughout the cut; otherwise, it can back up on you, just as a skew can.

I use the tiny radius of the tip as a detail tool on something like the bowl's rim or foot. Or I use it as a regular spindle gouge by placing the bevel against the wood and then using the side of the edge to cut from the peak of a bead to the base of a cove. It doesn’t take a skew's place, but when doing small-diameter beads and coves, it’s a terrific tool that doesn’t kick back on you the way a skew can.

Making bead jewelry with the 3/8" detail gouge

I remember spending an entire month back in the mid-1990s making beaded jewelry for my family just in time for Christmas. Every bead was made with the 3/8" detail gouge. It was fun matching beads left and right, and trying to get the right length and diameter of each bead was fairly easy. The hard part was getting a full volume in the curve of each bead. I think the smallest bead was 1/8" diameter, so it was a great challenge and a lot of fun. I made a total of five necklaces and two sets of earrings.

David Ellsworth, Earrings, 2000. Pink ivorywood, para kingwood. The cross pieces in the African Necklace and each of the earrings were off-center turned and then carved. The rivets holding the vertical pieces in the earrings are ⅜" long and ¹/₃₂" diameter.

David Ellsworth, African Necklace, 2000. Lignum vitae, curly maple, para kingwood, pink ivorywood, African blackwood; 11" high x 5" wide.

David Ellsworth, Cocobolo Necklace, 2000. Cocobolo rosewood burl, pink ivorywood, Sonora ironwood, African blackwood; 8" high x 5" wide. It took a few attempts to get my skew chops up to speed and to gear down to this scale. The difficult part wasn’t actually turning or matching the beads left and right; rather, it was getting the fullness of the curve in each bead.

The deep-fluted 85˚ bowl gouge gets its name from the angle of the bevel measured off the shaft's base.

This gouge is used for making cuts across the inside base of an open bowl, the inside of a very deep goblet, or around the belly of a bowl whose rim is narrower than its major diameter. Because of the extreme projection of the bevel, the shaft doesn’t strike the rim of the form, which makes it an indispensable tool for these types of cuts. It can be used either on face grain or end grain, so it’s excellent for cutting the final surface inside a goblet.

This gouge really illustrates the importance of riding the bevel when going through a cut, without which the cut wouldn’t work. It’s really a beautiful cut to make. The handle sweeps nearly a third of a circle as the cut shifts from the left side of the edge to the center of the edge.

Two types of 85˚ gouge: deep-fluted (top) and a modified Ellsworth side-ground Signature gouge (bottom). Note that the angle of the bevel on the end of both tools is 85˚.

How the 85˚ gouge works compared with the Signature gouge

The 85˚ angle allows me to reach areas in bowls with narrow rims not accessible with other gouges, such as the Signature gouge. I’ve cut a bowl in half to illustrate how these tools work. With its flute pointed straight up, the 85˚ gouge begins the cut with its left-side edge, shifts to the center of the edge in the curve of the bowl, and then to the right side of the edge to finish the cut across the bottom. By comparison, the 60˚ bevel of the Signature gouge is too steep to maintain contact through the cut on this narrow-rimmed bowl. For more on the Signature gouge, see page and Chapter 9, "Turning an Open Bowl with a Cut Rim," page.

Using the 85˚ gouge, I insert the gouge with the flute pointed straight up. The edge on the left side of the tip will begin the cut.

The cut then shifts closer to the center of the tip in the lower curve of the bowl.

Finally, the cut rolls to the center of the tip as it continues cutting to the center of the bottom of the bowl. Notice that in the progression of these cuts, the 85˚ bevel prevents the shaft from striking the rim of the bowl.

This attempt to cut with the left side of the tip using the 60˚ bevel on the Signature gouge only works going down the inside wall of this narrow-rimmed bowl.

Notice that in the lower curve, the bevel lifts off the surface because the rim is in the way of the shaft.

The Signature gouge cannot keep contact when cutting across the bottom of the bowl. Here, and also in the lower curve, I would use the 85˚ gouge as described above.

The back hand generates the force of the cut, while the front hand simply keeps the shaft pinned down to the tool rest. In effect, the back hand pushes the bevel directly into the wood, which forces the tip to cut to the right, as guided by the bevel, and through the fulcrum point on the tool rest. In the meantime, your feet need to be broadly spread apart and the knees unlocked so the handle is free to make the full sweep without the body being in the way. It’s very exciting. And it takes a little getting used to. But it’s easy to develop confidence as long as you keep the bevel pressed against the wood.

Another nice thing about this gouge is you can use almost any brand and almost any flute shape except a shallow flute from a spindle gouge. Just be sure there’s plenty of length and mass in the shaft and the bevel is kept at 85˚. When making a bowl, it’s not uncommon for me to hang the tip as much as 4" to 5" off the tool rest, so I use a minimum ⅝"-diameter gouge to gain maximum stability for the cut.

The Ellsworth Signature gouge is my own design, inspired by the designs of several other turners. The basic difference between my Signature gouge and conventional or traditional bowl gouges is its versatility, particularly the slicing and shear-scraping cuts that are made possible by the side-ground edge. There are also differences in the approach to the cutting process, specifically pulling the tool through the roughing and shaping of a form rather than pushing it, thus reducing fatigue and increasing efficiency. Finally, this tool allows for a very fluid approach to cutting the wood that allows for more movement of the entire body and, therefore, less fatigue. The Signature gouge can perform five cuts: the roughing cut, the slicing cut, the scraping cut, the shear-scraping cut, and the interior-finishing cut. In most cases, it is possible to turn an entire bowl using only the Signature gouge. I also turn the exterior of all of my hollow forms, large and small, with this tool.

To give a little background, I first experienced the side-ground–style of bowl gouge in 1982. Liam O’Neill of Ireland showed it to me, although Michael O’Donnell of Scotland, Ray Key of England, and Richard Raffan of Australia had also made variations of this tool design. In fact, at the time, I jokingly accused each of them of screwing up the grind on their traditional gouges and coming up with something new and better. In any case, I modified the shape of Liam’s tool tip so that the tool would perform more effectively for my own needs and provide a variety of cuts.

To make the interior cut, the 85˚ gouge moves from left to center in the bowl, with the bevel always in contact with the surface of the interior. Note the shifting in the direction of force through the cut.

Also note that what I call the Ellsworth Signature gouge refers to a ½"-and ⅝"-diameter bowl gouge with a side-grind and an uninterrupted parabolic flute. While I do most of my work with the ⅝" tool, the ½" diameter tool is fine for very small objects. However, because of its lack of mass in the shaft, it will vibrate when extended too far beyond the tool rest or when doing the shear-scraping cut on dense or dry woods.

On the other end of the spectrum, a ¾"-diameter gouge would put so much more edge into the wood it would be very difficult to control the cut. As such, the relationship between the length of the cutting edge, the diameter, and the weight of the tool can make a huge difference in overall performance.

Also important to the design of the Signature gouge is the flute's shape (see illustration at left and photo above). I prefer a uniform parabolic shape with an uninterrupted surface. This gives me a progressive convex curve to the edge that maximizes each of the five primary cuts the gouge will make.

Note the differences between the 85˚ gouge (left) and the deep-fluted 85˚ gouge (right). The shapes of the flutes are different, but the 85˚ angle of the bevels at the tips of both tools is the same. As such, they pretty much do the same thing, although the deep-fluted gouge might be best for the interior cuts across the bottom of smaller forms like goblets.

The Signature gouge is designed to make these five primary cuts so it will work with equal efficiency on the outside of hollow vessel forms, plus the outside and the inside of open bowls. I don’t recommend using it for spindle turning, simply because it wouldn’t be as efficient as a skew or a spindle gouge. But I certainly encourage people to experiment by using tools for a broad variety of applications, as long as they feel safe in doing so. In this respect, tool design is like language: It evolves with time and need. The history of the gouge is surrounded with experimentation; who knows what other turners might come up with?

These end and side views of the Signature gouge show the parabolic flute. The convex curve to the edge is what allows the gouge to make five distinct cuts.

For more detail on the five cuts and how to use the Signature gouge, see Chapter 9, Turning an Open Bowl with a Cut Rim, page.