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    Bowl-Turning Basics






    more on woodworking safety

    Tools and Materials

    The beauty of a well-balanced bowl lies in subtle details. A bowl that's meant to be used should invite human touch. Making one isn't beyond the means of even a beginner, as long as he's armed with a nice piece of wood and a few design concepts. And unlike other woodworking projects that require joinery and glue-ups, you can turn a small bowl in an hour or two.

    Taken in profile, the upper half of the bowl is turned with a gentle concave curve. The lower half is shaped with a reversed curve. Under typical overhead lighting, the reversed curve creates a shadow that emphasizes the bowl's form. The angle where the two concave curves intersect has a practical function, too: It provides a wide lifting surface. A shallow foot lifts the bowl, both physically and visually. And on the inside, the rim is undercut slightly, emphasizing the form and a sense of containment.

    A center-screw faceplate is a quick way to fix wood to the lathe for shaping the outside profile. When the bowl is remounted by its foot and is hollowed, I use a set of step jaws, which accepts three different foot diameters. I use a 1/2-in. spindle gouge for shaping the profile and a deep-fluted 1/2-in. bowl gouge for hollowing. A 3/8-in. spindle gouge comes in handy for detailing the foot. I use scrapers to clean up tool marks and tearout. For this bowl, a pair of 1-1/4-in. or 1-1/2-in. scrapers is used, one skewed for the outside curve and the other radiused for the interior. For sanding, I use handheld sandpaper and a portable drill fitted with sanding discs.

    This article originally appeared in the May/June 1999 issue of Fine Woodworking.


    How to Make

    Rough out the profile

    Shape the outside profileclick to enlargeWork the shape with a spindle gouge

    Shape the outside profile: Mount a bandsawn disc on a screw-center chuck. Set the lathe's tool rest about center height at an angle across the bottom corner of the blank. Spin the blank by hand to make sure it clears the tool rest. You may be tempted to true the outside of the disc first. Don't bother. Instead, begin by removing waste at the corner just above the foot, using the 1/2-in. spindle gouge. Place the gouge on the tool rest and roll it over to about 45° with the bevel facing the wood and the handle dropped about 15° to 20° below horizontal. Plant your left hand firmly on the rest over the tool, using it as a fulcrum against which the tool can pivot as you start the cut. Position your fingers so that they deflect the shavings. Move the handle with your body rather than with your hand: You'll get more power and control with less effort. Once the edge is cutting, start to squeeze the tool left along the rest with your left hand. By squeezing with the left hand as the edge pivots left, you take a broad sweeping cut, and you can adjust the thickness of the shaving by rolling the tool slightly with your right hand. This is a shear cut: As the tool moves forward, it slices into the wood. You're hogging away lots of material, and the surface will develop ridges. Adjust the rest frequently to maintain a gap of in. or less between it and the workpiece. Don't worry about the quality of cut at this stage. All you're doing is roughing out the profile.

    Shape the base and foot

    Shape the outside profileclick to enlargeSqueeze the edge into the wood

    True the base: For a bowl to sit properly, its base must be perfectly flat, or better yet, slightly concave. I use the 1/2-in. spindle gouge to rough out the base and foot (see cut 8 in the PDF version). It's easy to remove more wood than necessary when truing the base, so here's what to do. Lay the tool on its side as you did for the roughing cuts, then gently squeeze only the tool's edge into the rim of the base. Don't push the handle away. Hold it firmly against your body while cutting. Once the tick-tick-tick noise stops, you have a trued surface. With the edge of the base trued, roll the tool 180° so that the bevel rubs the wood for a shear cut from the edge into the center.

    Finish the profile with a few final passes

    Shape the outside profileclick to enlargeMark the size of the foot

    Work out the foot: Then use a pair of dividers to transfer the chuck-jaw diameter to the workpiece. Next, make cuts 9 and 10 in the drawing using the nose of a 3/8-in. gouge. The fingernail grind on this tool enables you to get into corners and tight spots. Start the cut with the gouge on its side, with the bevel aligned in the direction of cut (the flute will face away from center). The handle should be dropped 35° to 45° below horizontal; use your left hand to pin the tool firmly to the rest. For maximum control, bring the edge through an arc into the wood by raising the handle and then moving the tool forward across the rest only when the handle is near horizontal. If the gouge isn't right on its side, a catch is near certain as the wood bears down on the unsupported inside edge. Go gently in cuts 9 and 10 in the drawing, gradually reducing the diameter of the foot until you reach the marked diameter.

    Remount and hollow the bowl

    Shape the outside profileclick to enlargeMake shear cuts with a gouge and clean up with a scraper

    Finish the profile: Once the foot and base are complete, finish the bowl's profile (cuts 11 and 12) with a series of shear cuts. Using the 1/2-in. gouge, work from the smallest to largest diameter. The portion of the cutting edge doing the work lies 45° to the wood. To start the cut, use the same arcing technique as you did when turning the foot. If you get chatter marks, you're pushing the tool too vigorously into the wood. If the bevel isn't rubbing, you will get ridges. You cannot start a shear cut right at the top of the foot with a 1/2-in. gouge because there isn't room to rest the bevel. Take a very delicate shear cut against the grain here using the long nose of the 3/8-in. gouge, or try the right corner of a square-end scraper. Cut the upper curve in from each end to limit the possibility of unsupported grain splintering, particularly on the top edge. Again, start the cut with the 1/2-in. gouge on its side and bring the edge through an arc into the wood. A good shear cut will leave the surface ready for sanding, but you're not always that lucky. If there are patches of slightly torn grain, try shear scraping. Sanding out torn grain can take hours.

    Sand and finish the inside

    Shape the outside profileclick to enlargeUse the motor cover as an arm rest when sanding

    Hand-sand the bowl: I generally hand-sand the profile. Work through the grits beginning with 100, then on to 150, 220, 360 grit and finer if you feel so inclined. With the sanding completed, stop the lathe and slop mineral oil liberally over the bowl's surface. Then hold a block of soft beeswax against the spinning wood to build up a thin layer. Last, apply a soft cloth to the spinning bowl, which melts the wax into the pores. This is a safe finish for bowls that will be used for serving food.

    Shape the outside profileclick to enlargePush the drill bit into the hole left by the screw chuck

    Drill a depth hole: The wonderful thing about the new chucks introduced to the market in the last few years is that they allow you to remount the bowl by its why it's possible to finish the outside completely before tackling the interior. I own several sets of step jaws, which will clamp around any size foot, 8 in. or less. After remounting the bowl, true the top using a bowl gouge on its side. Then drill a depth hole in the center of the bowl. The depth hole does two things. First, it establishes the depth to which you will hollow, saving constant stops to measure as you go. Second, it removes the center of the blank, which is difficult to turn and is the source of many catches. A depth drill can be made by inserting a 1/4-in. or 3/8-in. twist drill bit into a shopmade handle. Measure the amount of the bowl that needs to be hollowed, leaving about in. of material in the base, and mark the depth drill. Use your thumb as a marker. Then turn on the lathe and push the bit into the hole left by the screw-chuck center until your finger reaches the workpiece. When withdrawing the tool, watch out: The metal and shavings get surprisingly hot.

    Shape the outside profileclick to enlargeRough out the inside

    Rough-cut and look for warping or an off-center base: Now you can get on with the hollowing using a deep-fluted 1/2-in. bowl gouge. Usually I work from the rim toward the center. The real hazard here is the tool kicking back as you start the cut, but this is easy to avoid if you start the cut with the gouge on its side and the flute facing center. If you start with the gouge flat and the flute up, it will catch every time. To start the cut, drop the handle 30° to 40° below center, then raise the handle to bring the edge through an arc into the wood, just as you did when roughing out the profile. Once the tool is in the wood, keep the bevel rubbing and rotate the tool very slightly counterclockwise to get larger shavings. It's best to rough-cut the bowl, then assess the situation. So before taking cut 17 (see the drawing), use calipers to measure the thickness of the wall and base. If you have a problem with the bowl running out of true or being off center or warping, now is the time to fix it by truing the upper curve of the profile. This bowl is designed with a flat rim. It's important that the inner and outer lips of the rim be turned on the same axis or the rim will be elliptical and look terrible.

    Shape the outside profileclick to enlargeUse a scraper to clean up tool marks and tearout

    Make the final cuts: When you come to the final shear cut (17), the bowl wall is somewhat flexible, so if you push too hard you'll have chatter marks unless you have your hand on the outside of the bowl to equalize the pressure of the tool. On the final cut with the 1/2-in. gouge, go as far around the curve as possible in one sweep with the bevel rubbing. Then switch to scrapers, which are easier to control, to finish the curve and bottom of the bowl. Aim for a 3/8-in.-thick rim. Slim the wall thickness slightly on either side of the profile angle. It is possible to shear cut right to the bottom of the bowl with a gouge, but I prefer the better control of a wide scraper with a radius slightly less than the curve of the bowl. You'll find cutting a broad curve easiest using a broad radiused scraper rather than one with a narrow, round nose. Although the scraper is 1-1/2-in. wide, use only about 1/2-in. or less of the edge at a time; otherwise, a catch is likely. This is not a molding tool. Keep the tool flat on the rest and sweep the edge through a broad arc to keep the curve flowing. Cuts should be light. Don't even think of scraping up the side toward the rim: The thin wall will flex and catch, and the bowl will likely blow apart. (With practice, you can shear-scrape this area.) Any small ridges or chatter marks in this area can be eliminated by heavy sanding.

    Shape the outside profileclick to enlargePower-sand using flexible sanding discs in a portable drill.

    I power-sand the inside of the bowl using cloth-backed self-adhesive discs mounted in a handheld drill. The power tool not only speeds up sanding, but it also helps maintain the sweep of the internal curve, especially across the bottom where hand-sanding often leaves a bump at the center. Right-angle drills are the easiest to control, but you might not be able to justify the expense for just a few bowls. If you do hand-sand and a bump develops across the center, stop the lathe and rotate it slowly by hand, sanding across center using a soft sanding pad to back the abrasive. A piece of foam rubber or rolled-up cloth works well. This ensures that the very center gets as much attention as the rest of the inside. Finish the inside of the bowl as you did the exterior, with mineral oil and beeswax. Wood is a wonderful knock-about material. A bowl like this handled with care will survive us all and look better for use. Wash it using detergent and hot water. And remember that whilst the first dent or stain of daily use is is a minor disaster, a thousand make a patina.



    Richard_Raffan