44 - Grinding Station, страница 10
TECHNIQUE Tips on Using a Skew ChiselCrisp, sharp details. And a glass-smooth finish. Two things you can depend on when using a skew chisel to turn a spindle on the lathe. The reason is simple. The blade of a skew chisel is beveled on both sides like a knife. This forms a cutting edge that peels off shavings like the skin off an apple. skewed edge. But it isn't a keen edge that makes a skew chisel such a versatile turning tool. It's the fact that the edge is angled (skewed) across the end of the blade, see drawing below. This skewed edge makes it ideal for planing the long grain of a spindle, see photo above. Yet it also lets you cut a shoulder in stubborn end grain or turn a delicate bead. (For more on this, refer to pages 11 and 12.) size. Depending on the type of cut (and size of workpiece), there are several sizes of skew chisels. k From planing a smooth finish to turning a bead, a skew chisel is a versatile turning tool. They range in width from W' up to 2". I've found that a ¥2" or %" skew chisel is fine for most work. tune & sharpen. Regardless of its size, it's worth taking a few minutes to "tune up" a brand new skew chisel, see box below. And as with most hand tools, a sharp edge is the key to getting good results, see box on page 11. DRT EDGE LONG EDG LONG POiNT CUTTING EDGE SHORT POINT SKEW ANATOMY HEEL Tune-UpThe secret to using a skew chisel is to slide (or roll) it smoothly across the tool rest. But sometimes, the sharp, square corners of the chisel can cause a slight "hitch." roundover. To prevent this, it's a good idea to "tune up" a brand new skew chisel by grinding a roundover along the short edge, see photo. Start by grinding several "flats" along the length of the edge. Then blend them together using silicon-carbide sandpaper, see drawing at left and detail 'a.' long edge. You may also want to knock off the corners on the long edge, see detail 'b.' This provides a more comfortable grip. And it keeps the edge from marring the tool rest. 10 ShopNotes No. 44 |
