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First get comfortable and stand close to the lathe so no reaching is required to make your cuts. Note too that the long handles are designed to be held comfortably to the body as the cut is made. This technique is called the three-point grip. The control hand is on the handle to position the bevel and to control the cutting edge. The other hand rests safely on the tool rest and grips the chisel securely. The chisel must always rest on the tool rest as any cut is made. Never allow your fingers or hand to be pinched between the tool rest and the work piece.
With the tool rest locked in place, the lathe is turned on and the cut is made with the flat of the skew blade held perpendicular to the tool rest and square to the workpiece.
After the cut is completed and the lathe is turned off you can see how the square corners of the turning blank have been sheared to help limit tear-out.
The cove cut is made by easing the cutting edge of the bowl gouge into the workpiece.
Try to rub the bevel to get the smoothest cut. My hand holds the chisel to the tool rest and steadies the gouge as the cut is made. With the lathe off, you can see the proper blade orientation. The chips and shavings should be coming off the right edge of the fingernail grind (a modified shaping of the tip for improved cutting, shown above right). The beauty of this bowl gouge is that it is ideal for both spindle and bowl or faceplate work. This is my favorite chisel because of its versatility.
Once again notice how the flute (the channel running the length of the blade) is rolled slightly to the right as the cut is being made from left to right.
This will allow the bevel of the chisel to rub the wood fibers and consequently support the cutting edge. The trick to this cut is to rub the bevel and engage the cutting edge at the same time. When done in sync the result is a super smooth sheered wood surface. That’s the magic of shearing. One tip: rub the bevel first then raise the handle slightly until the bevel and the cutting edge are working in harmony. When it works right that is called “the dance” in turning. If not, well your turning just got a little smaller. Don’t sweat it! Have fun and try it again! By the way, the roughing gouge is only used for spindle turning. It is too grabby for bowl or faceplate work.
The key to the roundnose scraper is to lower the tool rest and lock it in place so the cutting edge of the scraper is precisely at centerline. The roundnose scraper is like a steel cliff. The overhanging cutting edge is always on top. I like to use this scraper to cut uniform coves.
Just turn up the lathe to approximately 1,200 rpm and gently ease the cutting edge in to the proper depth. Open up the width of the cut as you go deeper to prevent the blade of the chisel from binding. Turn off the lathe to inspect the quality of the cuts often.
Look closely at the height of the locked tool rest in the photo above. The tool rest must be positioned so the bevel and cutting edge of the skew is approximately halfway between the centerline (the imaginary line connecting the point of the drive spur and the point of the live ball-bearing center) and the top of the work piece. Rub the bevel first then raise the handle slowly until the bevel and the cutting edge engage the work piece at the same time. The bevel must be rubbing the wood for this shearing technique to work properly. The shaving should come off of the skew’s edge about ?" away from the heel of the skew (the back part of the skew opposite the toe) and not quite to the center of the cutting edge.
A turning set.
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Lathe Turning's Fab 5
Lathe Turning's Fab 5
February 06, 2007
by Scott Phillips Few activities render the joy and creative expression that wood turning does. It is immediately rewarding to see shapes appear right before your eyes. Yet less than 10 percent of American woodworkers turn. Perhaps it’s just hard to get started. If that’s your excuse, I can show you how to make turning simple using only five basic turning tools. If you’re interested in learning to turn, read on. If you’re already a turner, you may learn how to simplify your craft by using some of your tools more efficiently. So what are these five wonder tools? If you become handy with these chisels, you’ll be a master in no time. They are (from left to right above) the 3/16" diamond parting tool (the cross section of the blade is diamond shaped), the 1-1/4" roughing gouge, the 1/2" bowl gouge (perhaps the most important), the 1" oval skew (its edges are rounded for easier use), and the 1/2" roundnose scraper. I recommend spending the extra bit of money to buy high-speed steel lathe chisels from Sheffield, England, for two reasons. First they hold their edge longer than high carbon steel, and second, if you do slightly blue an edge while sharpening on a grinder the chisel will still perform well. The best beginner turning project is an object locked between the drive spur and the live ball-bearing center. This is called spindle turning. To start, always set the lathe at the lowest speed setting when starting a new turning, then mount the workpiece securely between the centers. Adjust the tool rest as close to the edge of the workpiece as possible, rotate the turning square by hand to make sure no points contact the tool rest, then lock it in place. The next step is perfecting your stance. The photo shows how to do it correctly. Some good turning (and woodworking) habits are to remove all rings and jewelry and roll up your sleeves. Also, you should read, understand and follow all the instructions that come with the tools you use. Always work safely and wear a face shield while turning. The project I’m working on in this article is a candlestick pedestal. The turning blank measures 3" square and 16" long, and the bottom segment will remain square. Before turning the lathe on, I first adjust the tool rest so the cutting point of the lathe skew (called the toe) is right at or slightly above centerline, as shown in the photo (below left).Next the 1/2" bowl gouge is used to gently cut a sweeping cove (a cove cut is a cave-like cut). Make certain that the tool rest is adjusted and locked to allow the cutting edge of the chisel to be right at or slightly above the centerline. The flute of the bowl gouge is tilted slightly to the right. The photo (top) shows the proper blade orientation. You may have noticed the spalting that is beginning to show up on the work piece. These colors and zone lines of decaying maple are beautiful yet pose a serious health threat. Always wear a NIOSH class 2 dust mask when working with spalted wood, especially when sanding. Allergic reactions to these wood dusts can be severe. Once the corners are sheared and the sweeping cove is formed, use the 1-1/4" roughing gouge to remove the rough edges and create a smooth cylinder above the square base (right). Next use the 3/16" thick diamond parting tool to accent the candlestick pedestal by first cutting three identical slots straight into the workpiece (previous page). Then turn the slots into three beads. A bead is simply a bump. The fifth versatile lathe chisel is the 1/2"-wide roundnose scraper. Scrapers can be used to do just about every cut imaginable. In fact, if you have trouble with the shearing techniques, just use the scraper to get the profile close then add details with the parting tool. One final tip is for advanced turning. The lathe skew is primarily used by experienced turners to form perfectly smooth cylindrical shapes. This spindle turning (turning between centers only) technique is tricky to master, but follow the tips in the photo caption below to turn a perfectly smooth cylinder to finish the candle stand. These tips should allow you to enjoy the successes of turning your own masterpieces in only a short while. And remember what my father taught me years ago: Never tell anyone what you’re turning until it’s done, that way no one will be the wiser if things change shape along the way! Have fun! PW |
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