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The skew chisel. Learn to use it and see what it can do.

Lots of woodturners fear the skew chisel. Skews dig in alarmingly, seemingly without any warning or provocation. Some people don’t use them at all. But can you really call yourself a woodturner if you can’t use a skew chisel? It’s perhaps  the most useful tool of the lot for spindle turning, so it is worth persevering with it. Just watch Woodturner21’s videos on YouTube to see what the tool is capable of.
You probably already have some idea of how to use the skew chisel for cutting beads and planing a cylinder. You can find the basic principles in turning books and DVDs and I don’t mean to repeat them. All I can tell you is what you already know – that you need lots of practice – and show you how to get the most from that.

Tuning up

First, tune up your skew chisel. Although you can use different grinds, the default has a skew angle of about 70 degrees and a bevel length of about 1.5 times the thickness of the tool. A long bevel makes it easier to see what you are doing, though can make the chisel cut in deeper when you get a catch. Make sure the edge and the points are really sharp, and not rounded over.
A long bevel and straight cutting edge are easier for sharpening on an oil stone or diamond hone. It is OK to use either a straight edge or a curved one straight from a grinder. Try the edge on your thumbnail – if the edge or the point slides without biting in, it’s blunt. Make sure you keep the chisel sharp all the time you are using it, but grind away the sharpness from the long side edges of the tool so they slide easily on the tool rest.
If possible, use a strong, rigid skew of about 10mm square to practice beads (dealers sell these as ‘beading and parting tools’. They are easily ground to a skew angle), and one about 18mm wide for planing. Of course other sizes work perfectly well. But a short edge gives less scope for catching on a bead while cutting on the point, and a wider tool helps keep the long point clear on a cylinder.
Now check your tool rest. Make sure it is smooth. Rub it with a bit of wax to cut friction. Set it a little higher than for gouge cutting. This puts the skew’s handle in a more convenient place for you.

Set up the lathe

Have the lathe running slowly so you can see what is happening at the point of cut, and you don’t feel threatened by the spinning wood. Later you will probably want to use higher speeds. Put on your face shield, just in case.
If you are nervous, use a conical fixed centre (one without any teeth) in the headstock and a revolving one in the tailstock. Make a pilot hole about 6-8 mm wide and deep in the headstock end of the blank. The cone centre will give friction drive only, with nothing else forcing the wood round, and is safer than holding the wood in a chuck. You can adjust the tailstock until the friction is strong enough to drive the blank but it will stop turning if you cut too deep or have a bad dig-in.
Practice on soft timber.  Start with a blank you have roughed down into a cylinder of about 40mm diameter and about 150mm long. You may find bigger pieces intimidating, and long thin ones whippy, neither of which is helpful. Choose a blank that is straight-grained and without knots.

Practice

 Don’t try to make any specific item at first, just keep making beads and planing cylinders. Make beads of about 12-18 mm wide. Use a parting tool first to make a clear space either side of each bead for the chisel to work in.
Use the short point of the skew chisel for cutting beads, although it is possible to use the long point or the edge. Stick with the short point until you are happy with it – later you will try the long point and may end up preferring it. I think the short point is easier to start for many people.
The first few times, use a scraper to make a semicircular bead shape that you can then follow with the skew. The scraper seems easier, but don’t be tempted to keep on with it. When you see the difference in the surface the skew makes, you will understand why. Then, with the lathe switched off, present the skew to that rounded surface, first at the top and then moving down to the bottom of the curve, keeping the point in the proper cutting position as you go. The chisel will begin almost flat on the rest, and end on its side. See how you have to move the tool to keep the point in the right place. Repeat the movements round the curve, so your body begins to learn the action.
Although you will be cutting with the point, the bevel must float (not press) on the cut surface to support the tool. Twist the skew as you go round the curve to keep the point in the cutting position. The edge will be close to the wood, but don’t let it touch. If it touches when the lathe is spinning you might get a catch. When rolling the bead with the edge, the movements are slightly different.

Make a cut

When you are ready, switch on and take a cut. Go slowly so you can see what is happening. No rush. As slow as you like, if using a high speed steel chisel. Carbon steel can overheat if kept in the cut too long. Take a thin shaving. Steer the point all the way round the curve, repeating the movements you started to learn earlier. Try for a smooth, even cut and don’t put pressure on the wood.
Pay attention to the handle movements. They are what you are practicing. As you try to go round the curve, you may have a tendency to complete the movements either too early or too late. Either will make a poorly shaped bead.

Repeat

Don’t work too long on one bead, cutting too deep into the wood, because if the blank gets thin it will start to vibrate and could snap. Start a new one. You may find one side of the bead easier than the other. Concentrate on the easy side first, making half beads, until you understand the process and feel ready to change over. When you get a catch, start again on a fresh part of the blank. This is because the damage can interfere with the free movement of the skew.

Planing cuts 

Planing uses the edge of the skew chisel. Keep the long point up, clear of the wood. Have the cutting edge at about 45 degrees to the lathe axis, because that gives a slicing cut with the shaving coming off near the short point. The key is to keep the bevel floating, without pressure, on the freshly planed surface. It’s easy to let the handle lift a little, and immediately you will get problems.
At first sign of trouble, lay the handle lower. Feel for the position in which the cutting is smooth and quiet and easy. If the handle is too low, the edge just lifts out of the wood, so does no harm. As long as you long pay attention to keeping the long point clear of the wood, you should not get digs when planing. At the ends of the blank, let the cut run off the wood, not onto it, as there will be no bevel support at that point
When you can plane a cylinder without problems, you can try steering the cut to round over the end – this is another good way to make beads.
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