By Richard Raffan

Turning a simple bowl, as the author is doing hero, can teach you techniques that also apply to more intricate work.

build. The project is completed in three stages. First you turn the outside profile, fixing the blank to a screw center by what will be the top of the bowl. Then your half-formed bowl is reversed and held by the foot for hollowing. And finally you rcchuck your hollowed bowl in a jam-fit chuck to finish the foot.

Tools and Materials

You need three basic tools to make the bowl shown here: a long-and-strong, deep-fiuted Vin. bowl gouge; a heavy, 1-in. scraper with a slight curve; and either a long-and-strong, shallow-fluted '¿-in. gouge or a long-and-strong, shallow-fluted v*-in. gouge.

The shallow-fluted tool is best on the outside and the deep-fluted best for hollowing. I like gouges ground with rounded shoulders (see lead photo) because as you will see later, they can be used for shear scraping as well as shear cutting.

To hold the wood on the lathe you'll need at least a center screw chuck. Here, I'm using a three-jaw chuck to grip a lag screw that penetrates the wood about *A in. (See s £

To rough out the profile, hold the shallow-fluted gouge about 30* up from horizontal. Then raise the handle to pivot the cutting edge into the work and sweep the tool through an arc (left and center). The bevel doesn't contact the wood, as shown at far right.

The cleanest roughing cut comes from a back cut, where you shear with the full round shoulder on the inside edge of the gouge.

To true the base, squeeze your hand (left), pulling the tool into the uneven surface to flatten K, then turn the tool around and shear cut toward center (right).

photo *4.) The chuck's jaws are reversed to provide a stable base for the turning. Usually I use a dedicated screw chuck—either a manufactured one, such as the Craft Supplies screw center faceplate (available from Craft Supplies USA, 1287 E. 1120 S., Provo, UT 84601, 801-373-0917), or a shop-made chuck. (See sidebar, page 46.)

In these photos I'm turning Australian she-oak, but any seasoned wood that is stable and easy to work will do, including cherry, maple, box elder, Oregon myrtle and walnut. Air-dried wood is better to work and less dusty than kiln-dried. Avoid green timber for this project: chances are your finished piece will warp.

Mounting the Blank

Handsaw a disk 8 in. to 9 in. in dia. and about 3 in. thick, with the grain running across the face. The wood needs to be even-grained and without splits. Initially it's best to avoid blanks which are half sapwood,

The cleanest roughing cut comes from a back cut, where you shear with the full round shoulder on the inside edge of the gouge.

because the varying density between heartwood and sapwood causes dangerous vibration.

If you'll be mounting the blank on a screw chuck, flatten the surface of the blank (I use a belt sander) so that the face will lie flush with the chuck's backing plate. If you don't do this the blank will rock as you cut, making precise turning impossible and dangerous catches and flying blanks a near certainty. (The three-point support provided by the three-jaw chuck eliminates this problem.)

Once the surface is flat, drill a center hole and mount the blank on the chuck. Then set the lathe at a low speed, preferably 500 to 800 rpm. and standing away from the line of the blank, switch the lathe on for a few seconds to ensure that vibration is minimal. Your working speed should be between 900 and 1,200 rpm, but if you feel nervous about the speed, slow the lathe rather than risking an accident.

Roughing Out the Profile

An even-grained blank cut round on a handsaw will run pretty well true, so don't waste time trueing the sides of the blank first. Instead, set the tool rest at about center height and across the corner of the blank, and reduce the bulk as quickly as possible by turning away the corncr with the '/¿-in. shallow-fluted gouge.

When you are cutting, tilt the gouge about 30° up from horizontal and rotate it so that the flute lies around 45° off vertical. (See photo *3.) Use the lower edge of the gouge to make a series of cuts which sweep through an arc. (See photos «1 and «2.)

Take care particularly with the shallow gouge that you never present an unsupported edge to the wood (see Fig. 1): you will have a catch. This is because when there is no support beneath the edge, the downward force of the rotating wood snaps the tool over.

To true the base, squeeze your hand (left), pulling the tool into the uneven surface to flatten K, then turn the tool around and shear cut toward center (right).

FIG. 1: SUPPORTING THE CUTTING EDGE

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