Three Steps To A Sharp Edge

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s with other turning tools, sharpening the skew is a three-step process: grinding, honing and buffing.

Grinding—The bevel length should be about twice the thickness of the blade, which usually means an angle of about 30° to 35°, depending on the thickness of your skew. Grind each bevel on a fine-grit grinding wheel or belt grinder. The curve of the grinding wheel will produce a slight hollow grind.

Regrind when you've honed the edge so many times on the bench stone that there is no longer any hollow between the two flats produced by honing—the flat at the edge and the flat at the heel. You'll also need to regrind if you've nicked or damaged the edge.

Honing—After grinding the bevels, hone them on a flat bench stone,such as a fine India or a soft Arkansas stone. Place a bevel flat on the stone so both the edge and the heel of the bevel contact the stone. With one hand holding the blade or handle to maintain the angle, place two fingers of the other hand on the heel of the upward-fac-ing bevel. Push the skew forward and backward over the stone. Alternate between the bevels frequently to keep the cutting edge in the center of the blade. Rehone whenever you can see any bright spots along the cutting edge. You should blade with a fine-grit sharpening stone so that the tool can glide along the tool rest easily. A sharp irregularity or burr can catch on the softer steel of the tool rest.

Practicing the Cuts

There are three basic cuts you can make with the skew chisel: the planing cut, for smoothing the long grain of cylinders and cones; the facingoff cut for squaring up end grain on shoulders; and the rounding-over cut for rounding shoulders and turning beads.

To practice these cuts, mount a blank of clear, straight-grained wood (I recommend poplar because it's cheap and easy to turn) about 10 in. long and 2 in. square between centers. Round the blank with a roughing gouge to make a cylinder. Adjust the tool rest height so that the top of the rest is in line with the axis of the cylinder.

A note about lathe height: Proper lathe height is important to controlled cutting. It is especially important for the planing cut, because to get it right, you must maintain a consistent body position through the cut. To do this.vou must be comfortable, not hunched over. The rule of thumb is to position the headstock spindle at your elbow height, and then adjust up or down from there for comfort. Most lathes are too low. I'm 6 ft., 6 in. tall, and I needed to raise my lathe 4 in. to feel comfortable when cutting. I bolted a 2-in. thick maple plank between the lathe and the stand and then bolted 2 x 4s under the legs to make the 4-in. increase.

Planing Cut—The planing cut shaves the long-grain surface of the spindle smooth, much like a cabinetmaker's plane shaves a board. It is useful for truing up cylinders, and it works best on clear, straight-grained wood.

For this cut. position the tool rest high, about '/a in. to V* in. below the top of the cylinder, and about 3/i* in. from the wood. The speed of the lathe depends on the size of the blank and your confidence with turning tools. For planing a 2-in. diameter cylinder, I prefer a speed of about 2200-2400 RPM for planing cuts, but if you're just learning, I suggest starting with a speed of about 1700 RPM. To get a feel for the cut, you might

The pUming cut shaves the long-grain surface smooth. Hold the skew long point up and angle the tod slightly in relation to the wood's axis. Cut between the center part of the edge and the short point, and keep the bevel rubbing as you cut.

want to have someone turn the spindle for you by hand while you practice making the cut.

Begin the planing cut a couple of inches in from either end of the blank. Right-handed people usually start from the right end and left-handed people from the left end. If you're right-handed, hold the skew handle in your right hand, and hold the blade between the thumb and index finger of your left hand, with the long point up as shown in the photo. Reverse hand positions for left-hand turning. You can grip the blade with the thumb on top or bottom; I prefer it on top. You want the tool to feel balanced in your hands, and this is controlled by the position of the hand on the handle. If I'm using a 1-in. or I '/2-in. wide skew, I'll hold the handle in about the middle, along its length. If the skew is smaller than 1-in. wide. I find I need to position my hand closer to the blade to feel good control.

Once you're comfortable, support one corner of the blade on the top of the tool rest, and rest the heel of the bevel on the revolving wood. The tool should be angled slightly in relation to the axis of the wood as shown in the photo.

With the heel of the bevel rubbing the wood, lift the handle of the skew very slowly, using the tool rest as a fulcrum. The object here is to lift the handle just enough so that the edge of the tool begins to engage the wood. Cut between the center part of the edge and the short point of the skew, but don't cut too close to the short point. At first the cut will produce only powder. Lift the handle a little more and fine shavings will not be able to see light on the edge at all.

Buffing —Buffing the edge on a muslin or felt buffing wheel removes the burr created by honing. I charge the wheel with a stick of gray, emery buffing compound (available from Woodcraft, 210 Wood County Industrial Park, P.O. Box 1686, Parkersburg. WV 26102). If you don't have a buffing wheel, you can use a hard Arkansas stone or a strop to remove the burr.

Lightly press each bevel against the wheel. If you're too heavy-handed you'll round over the edge you just honed on the stone. If you're u^ing a stone or a strop, place the bevel in the same position as for honing, and drag it backward along the abrasive surface. Do this on each bevel until the burr is broken off. If a very fine burr remains, remove it by making a cut across the grain in a piece of soft wood.

I like to rebuff before I make the final finishing cut for a shape so that I can get the smoothest possible surface.—/?./?.

FIG. 2: FACING-OFF CUT

headstock

TA1LSTOCX

Angle tool so bevel is perpendicular to axis of wood.

FIG. 2: FACING-OFF CUT

headstock

TA1LSTOCX

Angle tool so bevel is perpendicular to axis of wood.

The facing-off cut is used for smoothing end grain. Lower the point in an arc into the wood. To face off the opposite shoulders, switch hands and cut with the opposite bevel.

appear. Once you get a shaving, it's important to keep the bevel rubbing against the wood as you cut. If the tool starts to chatter, you're probably lifting the handle too high, engaging the edge without rubbing the bevel. Lower the bundle a little and make sure the bevel is rubbing the wood. Experiment with different angles to see the results you get.

When you get a good shaving, move the skew along the cylinder, keeping the blade firmly supported against the tool rest. Try to keep your body in the same position relative to the lathe as you move through the cut. If you need to plane only a short length of the cylinder, just shift your weight from one foot to the other. To plane the length of the entire cylinder, you need to do a sort of waltz-like movement to the side— what I call the woodturner's box step.

When you're learning, you'll occasionally catch the edge of the skew in the wood. A catch makes the blade of the tool slam down violently onto the rest and leaves a nasty scar on your work. It will startle you, but the tool can't recoil back at you. You're less likely to lose control if you keep the tool firmly supported on the tool rest, keep the bevel rubbing during the cut, and avoid cutting above the center point of the edge. If a catch happens, take a break. Come back in a minute and turn away any scars on your work with a gouge before trying the skew again.

You can also make the planing cut with the long point of the skew down. This requires you to hold the tool at a much more acute angle to the axis of the work. Try to cut between the center of the edge and the long point.

Faeing-Off Cut—The facing-off cut is used for smoothing end grain, either on a shoulder, or for facing off the ends of a spindle. Sanding end grain on the lathe is torture, and this cut smooths end grain so cleanly that you only need to use fine-grit sandpaper to finish.

To prepare for practicing this cut, make a series of parting-tool cuts on the cylinder to expose end-grain surface. Position the tool rest at, or slightly below, the centerline of the cylinder and as close to the wood as possible. Revolve the cylinder by hand to make sure it isn't touching the rest.

Start with a left-hand shoulder formed by one of the parting-tool cuts. Place the skew on the rest, long point down, with the handle angled slightly to the right so the left-hand bevel is perpendicular to the axis of the wood, and in the same plane as the shoulder you plan to cut. (Use the right-hand bevel for facing off a right-hand shoulder.)

Begin the cut with the long point of the skew slightly high, raising the handle of the skew slightly to pivot the point in a smooth arcing cut that removes only about '/w in. of wood. Keep the bevel rubbing on the shoulder throughout the entire cut, and cut with the bottom section of the edge, at the long point. When you reach the smaller diameter made by the parting-tool cut, pull the edge out of the cut.

The surface left by the facing-off cut should be flat

Round off the shoulders to produce heeds. Roll the skew in the direction of cut in a smooth, flowing motion by twisting the handle. The skew starts flat on its side and ends up on edge at the end of the cut.

and smooth with no noticeable ridges. If there are ridges, it's because you rocked the tool to the side and the bevel stopped rubbing on the shoulder.

Again, the worst thing that can happen during this cut is a sudden catch. The problem is usually caused by cutting above the center point of the edge. If this unsupported edge, near the short point of the skew, touches the wood, the skew can flip over onto the flat of the blade and slam down hard against the tool rest. Cut below center, near the long point, keeping the tool firmly against the rest,and you won't have a problem.

V-Groove Cut —This cut is a simple variation of the facing-off cut that's used for cutting grooves. This is the only way to make a clean V-shape on a spindle, because you can't scrape and sand a V-shape without losing the sharp definition.

The technique is the same as the facing-off cut except that the bevel enters the wood at an angle, instead of perpendicular to the axis, to account for the angled shoulder ol the groove.

First, make a very fine line 011 the wood with a pencil to mark the center of the groove. Start the first cut slightly to the left of your mark, and make a shallow arcing cut with the long point of the skew to the desired depth of the groove. Then make a mirror cut on the right side of the mark to complete the V-shape.

Rounding-Over Cut—Rounding-over cuts are useful for turning beads or rounding off shoulders. These cuts can also be made with a gouge, but the skew is very efficient, especially if you already happen to have

If you hold the skew at the wrong angle, the edge can catch, slamming the tool against the rest and leaving a nasty scar on your work.

the skew in your hand.

For practice, you can start by rounding over the corners of the shoulders you already faced off on your practice cylinder, to make a row of beads. You round a bead in two steps—first rounding one shoulder, then the other.

Position the tool rest slightly below the axis of the cylinder and as close as possible without actually touching the wood. Hold the skew on the rest with the long point up. You'll be cutting with the section of the edge near the short point.

With the tool handle held low, rest the bevel on the wood near the center of the bead. Decide which shoulder you want to round first —right or left. In one smooth motion, raise the handle slightly to engage the edge, then roll the skew in the direction of the cut by twisting the wrist of the hand holding the handle. At the same time, move the tool forward slightly with the fingers of your right hand, keeping the skew firmly against the rest at the same time. It's a smooth flowing motion that takes only a second. The skew starts out flat on it's side and ends up nearly on edge at the end of the cut.

The key to a successful cut is to keep the bevel rubbing as you roll the tool (Only a small portion of the bevel is actually in contact with the wood.) and to make the cut in a single smooth, decisive movement. Don't cut above the center point of the edge, or it will catch and slam the tool down on the rest.

Repeat the cut to round the other side of the bead, using the opposite bevel and rolling the skew to the opposite side. On a large bead, you may have to round each side in two or more cuts. Start near the shoulders, and begin each successive cut closer to the center of the bead. Your last cut, on either side, should start at the center of the bead. By varying the amount of twist and depth-of-cut, this technique can also be used to turn cone shapes.

Ron Ruszkiewicz and Phyllis Si raw arc co-authors of the books, The Woodturner's Companion (1984, Sterling Publishing Co.) and The Woodturner's Art (l986,Macniillan Publishing Co.) They wrote about the spindle gouge itt the January! February, 1989 AW.

The delighted faces of your children as they work on their masterpieces make this easel a worthwhile project.

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