Coves and Beads Turning Techniques on a Lathe Machine

Once you have your chucks and lathe tools (and you can sharpen them), it’s time to do some turning-and have some fun. In this article, I will show you how to get through the basic tool moves without problems. I think gouges are the gateway to understanding tool use. If you can use a spindle gouge and a bowl gouge well, everything else will fall into place. It is like learning your first computer program. The rest are different but similar.

Coves and Beads

All spindle-turning shapes encompass the turning of either a cove or a bead, and mastering these two shapes will allow you to turn virtually any furniture spindle. Coves and beads are like compulsory figures in traditional ice skating-you can never practice them enough. Let’s start with the cove, which can be cut only with a spindle gouge.

CUTTING A COVE

In its simplest form, a cove is a U cut down into the surface of a cylinder. The key to cutting any cove is to obey the Law of Perpendiculars; the illustration of a simple cove on p. 1 66, with perpendiculars constructed at four points, depicts this theory.

The idea is to start at the top edges of the cove and take a series of scooping cuts, always ending at the exact bottom. Start at the left edge of the cove with the gouge almost on its side and the flute pointing toward the center of the cove. Bring the gouge to the center of the cove, rolling it to horizontal as the cut progresses. Next, repeat the motion from the right edge of the cove. Take a series of scooping cuts from each side until the cove is cut to the desired profile. Always cut downhill from the larger diameter to the smaller, and don’t cut beyond the center of the cove bottom.

Rolling the gouge as the cut progresses is only part of the story. In addition to rolling, you must angle the tool left or right and slide it slightly forward to keep the bevel rubbing. A common mistake among beginners is to lock the handle of the gouge in one position against the hip and simply roll the tool in the prescribed manner. A catch is always the result, since the cove cut is not as simple as it seems. You’re actually cutting a complicated compound shape, and if you simply roll the tool, you’re not keeping the bevel rubbing. The illustration on the facing page shows the correct tool alignment. Pay particular attention to the handle and the large amount of left, right, and up-and-down movement required.

The most frequent mistakes when cutting a cove are failure to roll the gouge sufficiently ( it should start almost on its side) and failure to angle the tool left or right sufficiently to have the bevel rubbing at the start of the cut. You must also slide the tool very slightly forward as the cut progresses because the diameter of the billet at the bottom of the cove is getting smaller, so the tangent point to the surface is moving away from the tool rest.

Another common mistake is using a gouge that is too wide for the cove. The cove must be wider than the gouge. Thus, it’s useful to have a range of spindle gouges for cutting different-sized coves. I try to use a gouge that’s about three-quarters the size of the cove I plan to cut.

CUTTING A BEAD

The bead is the opposite of the cove, both in shape and in the way, it is turned. It can be cut with either a gouge or a chisel (skew or beading-and parting tool). Although it’s exciting to cut beads with a skew a gouge is much better suited for beginners if not all turners. Cutting a bead with a spindle gouge is simple and straightforward, whereas using a chisel requires a precise sense of being flat on the bevel.

As a woodworker, I find that I do my turning in spurts when I need parts, and there are usually long lulls between sessions. After such a hiatus, it takes an hour or so of turning for my skills to return. During this acclimatization period, I’m hard-pressed to turn a bead with a skew and I frequently catch, though once I’m back in the groove again it’s a simple matter. Therefore, the only beads I cut with a skew are during turning demonstrations to show others how to do it.

When making furniture, whether professionally or for your own pleasure, time is money. You’re dealing with expensive billets of wood that take time to prepare, and you can’t afford to waste them. A catch with a chisel is a catastrophic event that generally relegates the work to the firewood pile. Even if this only happens once in every six or eight pieces, it’s still a great waste. You’ll save time and money by taking the time to reach for a gouge. Therefore, I strongly recommend that you use a gouge exclusively for cutting beads. Not only will you cut a cleaner bead of better profile, but also, you’ll have a better rate of success. Reserve the skew for planning cylinders and gentle tapers.

The first task in cutting a bead is laying it out. Experience will allow you to draw two pencil lines to mark the width of the bead, then proceed to cut it directly into the surface of a cylinder. At first, you’re better off using the toe of a skew chisel to demarcate the limits of the bead. Although you can cut a bead directly into the surface of the cylinder, it’s a good idea for beginners to cut away the area on either side to leave a raised square ridge, properly called a rondel. Raising a rondel first allows you to cut your bead without the worry of the bottom edge of the gouge catching on the adjoining surfaces. To raise the rondel, use the toe of a skew chisel as described for turning square to round with a shoulder, then use a parting tool to remove the adjacent material.

Cutting a Bead with a Gouge

The beginner is well advised to start by cutting away either side of the spot where you are going to cut your bead to form a ronde! A rondel is no more than a raised ridge, but it will help you cut your first beads with plenty of clearance to the left and right.

 1. Begin with the gouge flute up at the center of the rondel.
1. Begin with the gouge flute up at the center of the rondel.
2. Angle the tool to one side and roll it downhill, sliding it back slightly on the tool rest.
2. Angle the tool to one side and roll it downhill, sliding it back slightly on the tool rest.
3. Raise the tool handle and push forward as you) approach the bottom of the bead. The handle has to be brought around to the right a bit as well to keep curvature to the bead. The cut ends with the gouge dead on its side with the very tip cutting. If you pushed farther, you would go through the exact center of the work.
3. Raise the tool handle and push forward as you) approach the bottom of the bead. The handle has to be brought around to the right a bit as well to keep curvature to the bead. The cut ends with the gouge dead on its side with the very tip cutting. If you pushed farther, you would go through the exact center of the work.
4. Return to the center of the bead and start cutting to the left. Repeat the procedure on the other side.
4. Return to the center of the bead and start cutting to the left. Repeat the procedure on the other side.

Correcting Mistakes

EVERYBODY, EVEN AN EXPERIENCED turner, makes a mistake at the lathe now and then. Although it’s tempting just to throw the work in the corner and start again, there are a number of ways to sweep the blemish under the rug, so to speak. For example, you can widen or slightly deepen a cove and cut beads to a lower profile. You’re probably the only one who will ever know about such subtle changes. If you break a piece off a bead, you can glue it back on (assuming, of course, that you can find it amongst the shavings under your lathe). If you can’t find the chip, you can always plane the spot flat with a hand plane, glue a new piece on, and re-turn the work. You can often turn a chipped corner or bead to the inside of the finished piece of furniture during assembly. Just think of it as “antiquing.”

A handy glue to use for repairs is cyanoacrylate, or Super Glue. To fix a small blemish caused by a catch, fill the area with glue and sprinkle some shavings into the glue. On some woods, this can be a very convincing fix. Cyanoacrylate glue is also good for arresting checks at the end of a workpiece and for gluing small objects to a glue block.

Cyanoacrylate glue is available from woodworking suppliers and model shops in three viscosities: water thin, medium (my preferred grade), and thick. A catalyst is also sold that will speed up setting time to 20 to 30 seconds. Take care when working with this glue, since it will glue skin instantly. Avoid the temptation to hold the work with your fingers while the glue sets, or you may end up glued to the work. Cyanoacrylate glue is also very irritating to the eyes, so always wear safety glasses and work with plenty of ventilation.

For architectural turnings that are going to be painted, you can patch holes with auto-body putty (Bondo is a common brand). This material can even be used to replace broken beads: Patch the break with a blob of the putty, then re-turn.

Stick shellac works wonders for small blemishes. If you use a black stick shellac on cherry, it will look just like a pitch pocket. Remember there are no mistakes, just new design opportunities.

Whether you’re starting with a rondel or cutting directly into the surface of a cylinder, start in the middle of the bead in a classic shear cut, with the gouge held at 90° to the axis of the lathe and the flute facing up. If you’re cutting into the surface directly, you’ll have to open up the areas adjacent to the bead slightly-either with your gouge or with the toe of a skew.

To cut the left side of the bead, angle the tool left, slide it back slightly on the tool rest, and roll it in the direction of the cut. Next, raise the handle until the tool is on its side and aimed at the center of the work (the tool is now aligned with a radius of the work). Push forward until you reach the bottom of the bead. As the cut progresses, you’ll also have to swing the handle around behind the tool to create the curve of the bead and keep the bevel rubbing.

Most beginners fail to lift the handle high enough or roll the tool exactly on its side at the final stage of the cut. With the tool rolled only 45° and the handle raised only slightly, the result is invariably a catch on the adjoining surfaces. Another common mistake is failing to swing the handle around behind the cut but rather simply to push the gouge forward to the bottom of the bead, which results in a 45° flank instead of a rounded form.

To cut the right side of the bead, return to the center and reverse the procedure. Most beginners have difficulty making both halves of a bead symmetrical, but this comes with practice. The nice thing about using a gouge is that you can easily fine-tune a lopsided bead by re-cutting it by halves. Although you can do the same thing with a skew, it’s much more difficult to produce a bead with a flowing profile.

One final note about beads. Most people today think of a bead as simply an oval ridge on the surface of a cylinder. In former times, however, turners always took the toe of a skew and incised a small groove, or bevel, at each edge of the bead where it meets the cylinder. On most furniture turnings, this grooving entail only a light scribing cut with the toe of a skew, while on larger architectural turnings, a definite groove is incised with repeated cuts of the skew.

Beveling the bead is a basic technique that adds tremendous visual impact to any turning by giving depth to the bead and setting it off from the surrounding spindle. On architectural turning, the bevel gives paint a place to flow, preventing a buildup of paint at the transition point and a loss of visual impact. One reason that machine turnings look so lifeless is that they’re made on cutter head lathes that cannot cut bevels or undercuts. As a hand turner, you have a real advantage in creating shapes that can grab the eye of the viewer.

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