The skew has gotten a bad rep. I know of no other tool that evokes such groans and laughs, yet leaves such a superb finish, adds such crispness to the work, or is as versatile as this angled piece of flat steel.
This is primarily a "between centers" tool, useful in making such things as balusters, bed posts, tool handles, table legs, ink pens, eggs, Christmas tree ornaments, porch columns, and the like. I rarely use this tool in face-grain bowl work, except to add a shadow line on a detail or shallow cuts as decoration.
I trace most of the problems that folks have with the skew to simply a poorly ground tool, lacking a truly keen edge. Simple as this tool is, it has subtlety in its form and requires as fine an edge as would be desired on any carving gouge or paring chisel.
The first step in using a skew is making the shape serviceable. The chisel is "skewed"; rather than straight across, primarily to serve as a built-in clearing angle, to provide an unobstructed view of the cutting point or edge in several cuts, and to make it more adaptable for a variety of cuts than if it was ground straight across. The angle of skewness is about 70° from point to point. Significantly more or less from this standard causes problems--either lacking sufficient clearing or viewing angles or making it more "tipsy." The bevel length and angle is somewhat critical--we need it somewhere between a straight razor and a splitting wedge. Balancing the ability to obtain keenness with support is the challenge. Rather than discussing angles, I like to recommend lengths--a bit easier to visualize and measure. For general use, make the bevel length 1-1/2 times the thickness of the steel.
For a bit of refinement, you might try softening every part of the skew, other than its cutting edge. I suggest you chamfer the corners behind the long point all the way to the ferrule--but retain the flatness of this edge. On the short point side, do all you can to roll the corners away, even producing a completely rounded edge all the way to the ferrule. I find this type of grinding is best done on a belt grinder rather than wheel grinder. I have personally not cared for manufacturer's attempts to help the tool glide and roll easier--whether with attachments to the tool, rounding both of the corners (long and short point sides), or round/oval skews.
My personal choice is a heavy weight (at least 5/16" thick) piece of rectangular stock, in high-speed steel, and shaped to the above recommendations.
Should the edge be straight across or curved? I suggest you learn on a straight skew and then give the curved one a chance. The curved edge is definitely my first choice for its subtle advantages in curved cuts and for planing with the skew. Actually the curved edge starts out straight and then breaks into the curve but still maintaining approximately 70° from point to point. However, the curved edge is a bit harder to grind, and its advantages are not dramatic--if you struggle with a straight skew, you will have trouble with the curved edge.
Perhaps sharpening the tool is the single most important step in gaining consistent results and building confidence. The skew, like all my cutting type tools, has a slight hollow ground edge lacking multiple facets. I grind on an 8", 1725 rpm grinder, with a rock solid tool rest. I use 60 grit white wheels in a J or K hardness.
Sharpening.When grinding a straight across skew, simply treat it like a large parting tool, keeping the cutting edge horizontal while grinding. The curved skew is done basically the same, except you must rotate the tool to keep the curved edge as horizontal as possible.
I may also power hone on an 8" diameter MDF wheel,
charged with white buffing compound--always with the wheel moving away from me!
I hone the tool between grindings with a flat diamond hone with a
"fine" grit. Be mindful that all honing is secondary to effective
grinding, as you can not hone a tool with many multiple facets.
Honing the long point. You will never get keen points unless you hone the upper and lower edges of the tool. These points must be as sharp as the long cutting edge to perform well when they lead the cut.
SAFETY & CONFIDENCE MEASURES
Wear a face shield! I know that glasses and goggles are sometimes worn, but a face shield offers more protection. You will be less jittery when you have to place your face close to a cut.
Use a dead center to drive the work, rather than the spur center you are used to. Turners have used this method since at least the 1940's--a great strategy to create a slip clutch that regulates the amount of drive or to remove the kick that comes from a major catch. I tend to modify the standard dead center to give it a little more bite when working woods like Hard Maple or Cocobolo, otherwise you might get too much slippage when trying to work at normal speed.
Modifying the dead center. After the outside edge of the dead center has been sharpen with a mill file (lathe running but at low speed), grind 4 or 5 shallow scallops into the rim using a small grindstone in a drill or Dremel-type tool.
I sharpen the outside ring with a fine mill file, followed by grinding small scallops into the same ring. I then drive the center into the piece using a dead blow mallet. Frankly, I seldom use a spur center in my own work, only until I reach pieces of 5" or greater in diameter. As an added bonus, driving with a dead center allows me to re-center pieces that have been taken off the lathe or to flip a piece end for end, all the while keeping the original center.
You will need to practice with this tool before you rush into projects. Just like any learning venture, you will make mistakes. View this as feedback for correction, make changes, and try again. Would you believe you could learn the skew for $1.98? Buy two 99¢ 2"x4" studs, 8-feet long, in "white wood" (usually Spruce or Pine and normally very soft), ripped into 1-1/2" squares and cut into 8" lengths. You might want to eliminate the worst knots, just to make life a little easier. By the time you have worked the approximately 32-feet of soft material, you will have learned quite a bit about the skew.
Prepare the lathe for skew work. Make sure the tool rest is free of any nicks or crevasses. Either file or grind away the defects or replace the tool rest. A few turners prefer to wax the top surface of the rest prior to doing a bit of skew work. Speed does not seem to be as critical with this tool as with some others. Err on the side of caution, keeping the rpm in the 1000-1200 range for the suggested practice sizes.
When I first started, I only found one cut described in my turning books--the planing cut. That is a great cut, but there are many more. I will take you through a few of these.
Planing Cut. This is a leveling and finishing cut for cylinders, flats and tapers. I normally make this cut with the short point down, held approximately 45° to the axis of the lathe. The sweet spot on the tool is from the center to just above the short point. If you run the short point into the wood, it tends to rag the fibers, although this actually can be used to work to a detail or even to control bouncing. However most of the time, I cut above that lower point. If you cut above the center of the tool, you will discover a certain tipsiness and some loss of control. If you get too close to the long point, you will discover the sensation of a dig-in.
Other problems with this cut involve spiraling (slash, skating, or screw threading) and ribbing. Spiraling is caused by loss of bevel support, which may even throw the tool into a dig-in. Develop the habit of moving the tool in this order: tool rest, bevel on wood, and lift handle until it cuts but not beyond.
Ribbing is a quite different problem, caused by either the wood flexing or the tool bouncing. Check for sharpness, as this is usually the culprit. If the tool is quite sharp, then you may be pushing too hard into the wood at a right angle. Try to direct your pressure more along the axis of the lathe. And finally, if all else fails, place your hand directly behind the cut to reduce the flexing or bouncing.
Planing Cut. This photo illustrates the planing cut, leading with the short point down. The feed rate, speed of lathe, and angle of cut can all be adjusted to obtain the cleanest cutting action.
Roughing Cut. On diameters of 2" and smaller, I usually rough with the skew. It is marvelous for removing the corners and rapidly producing a cylinder, especially on shorter work. It is simply the planing cut applied to a rough block. I sometimes rough at a higher speed than I do the finish work--just to give a bit more support to the tool. On work of 12" or shorter, begin in the middle and push to the right until the block is nearly a cylinder. Next, start again in the center, but push to the left. Finally, I do a clean up planing cut the entire length of the piece to prepare the blank for detailing.
As far as sizes of the skew goes, I use two sizes almost exclusively. For the planing and roughing cuts, I prefer a larger skew, say about 1-1/4" for work 3" in diameter or less. The larger size gives me more of a sweet spot to make these cuts. For rolling smaller beads and finer detail, I prefer the 1/2" skew. Both should be made of high-speed steel, as there is a tendency to blue the points, both in grinding and in use.
Roughing Cut. A rapid way to remove the corners on smaller and shorter work is to use the skew in the planing cut angle of attack. The cut may produce excessive chipping in woods, such as Oak, Hard Maple, and many exotics. In that case, use a roughing gouge.
Vee Cut. This particular cut is the foundation for a number of related cuts. All are done with the long point down. The basic cut is achieved by arcing the tool into the cylinder until resistance is felt, but short of burning the wood. The first cut is made 90° to the lathe axis, while subsequent cuts to deepen the cut are made at angles of approximately 45° on both sides of the initial cut.
This seems like such a simple cut, but it is easily blown. Common causes of failure include a dull cutting point, a failure to make a deliberate entry into the wood, or simply pushing the tool straight into the wood. To assure a keen point, hone both sides of the cutting edge, followed by honing the long point top edge. If you can see any glint on the tip of the long point, you still have a dull tool for this cut. When starting the cut, let the point gently touch the wood until it has lightly scored the surface then complete the cut. This momentary hesitation is especially important on dense woods; otherwise you are inviting the skate or spiral. Finally, make the cut a slicing one, but keep the handle low and arc the tip into the wood. When executed properly, this cut leaves a fine finish even on very softwoods.
The uses for this cut are many: it is far better than a pencil for laying out the placement of details, if you deepen the cut for laying out beads (even if done with another tool)well, you're almost there; for duplicating just one piece, you can hold the original behind the roughed out cylinder and strike the critical layout points with the skew; to add shadow or accent points on completed details, decorative lines, and circles; and to lay out miniature beads, followed by a light rolling of the tip to complete the shape.
Vee Cut. The vee cut is an excellent way to highlight a detail, produce shadow and decorative lines, layout, or undercut a bead for a slightly different look. To make the cutting action more viewable, I lead with the long point down.
Shoulder Cut. We all know the effect on end-grain of using a parting tool to cut a square shoulder. It is usually a complete disaster, almost impossible to solve with sanding. Anytime you have an exposed square shoulder in-between center work, the skew is a great choice for the finish cut.
The foundation for this cut is the vee cut. Everything holds except a couple of small changes: line up the point square to the shoulder, but angle the long cutting edge away from the shoulder a few degrees. This slight angle which appears as a dark vee once the cut is underway is know as the "clearance angle." Generally, the closer you approach zero clearance, the finer the finish. The problem being that if you eliminate the clearance angle part way through the cut and rock the long cutting edge into the face of the shoulder, you get a slash that travels out of the shoulder and along the surface of the work. If you open the clearance angle too far to avoid these kinds of problems you're back to the tear out experienced with the parting tool. Also, be sure to start the cut high on the work and end above center. And finally, make the cuts rather light. The softer the wood, the less material you can remove to achieve a really fine finish. I seem to take three or four cuts, where I would really like to take only one.
Shoulder Cut. Perhaps the best way that I have found to cleanly cut a square shoulder is with the long point of the skew. The subtlety is in the few degrees of clearance of the long edge away from the shoulder (exaggerated here a small amount). When turning, this angle appears as a small black "V."
Rolling Cut. This is certainly one of the more difficult cuts of between center work, but perhaps the most rewarding when it works. This cut is appropriate for rounded beads, domes, egg shapes, etc.--anywhere we have a convex detail that depends on a curve rather than a flat line. The difficulty seems to be in the fact that there are a number of motions which must be added to the cut for proper execution: an arcing or twisting motion, advancing the tool towards the smaller diameter, moving the tool down the tool rest (unless the detail is small enough to allow a simple pivoting of the tool), and raising the tool handle to insure continued bevel support. You may approach the cut with either the long point up or down which will affect whether the cut is made with the long or short point in the lead. Unless it is a very small bead, I tend to lead with the short point down.
There are several ways to approach this cut with the skew, but I will explain a rather controlled and, therefore, more predictable method. Lay out the bead with a series of vee cuts. Using the short point itself, enter the wood just to the center of the bead on either side. I generally make two or three passes on each side of the bead taking small cuts until I'm satisfied with the shape. The fluffed up fibers created by leading with the short point actually serves the purpose of helping maintain bevel contact throughout the rolling action of the cut. It may also be noted that the initial motion of the point into the wood is a gentle pivoting action, often combined with a pause or hesitation as it rocks into the wood to be assured of a clean entry. And you might try rotating the wrist into a cocked position to begin the cut (somewhat uncomfortable) that unwinds with the cut and ends in a natural position (comfortable) as the cut finishes.
You may also find that one side of your bead may either look better than the other or that your failure rate is much higher on one side of the bead versus the other. Obviously, you must learn to be adept at both sides of the bead. One method of developing this skill is to place a 6"-8" length of material on the lathe. Part in the center to about half of the diameter. Practice the rolling cut on the section to the right of the parting line (which would represent the left side of a bead) until you are almost to the end of the piece. Return to the center and work to the left. If the difference is really dramatic in terms of one side being much harder to execute, then simply do the entire practice piece as a right or left side of a bead. When things start improving, return to making complete beads.
Rolling Cut. This cut will require some practice to get consistent results. The cut may be made several ways with the skew, but leading with the short point--making 2 or 3 cuts per side of the bead--is a very controlled approach.
That's a few of the cuts from this remarkable tool. Practice until they seem natural and predictable, and the fear is gone for using the skew for a "keeper."
Alan Lacer of River Falls, WI is a professional woodturner and a Past-President of the American Association of Woodturners. He will be conducting woodturning seminars at The Woodworking Shows in Seattle, WA (Nov. 9-11, 2001) and in Denver, CO (Dec. 7, 2001). He also has a forthcoming video on the skew chisel, planned for release in January, 2002.
Woodworker West, November-December, 2001
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