Powermatic 4224B Bowl Turning Techniques, To Shape Outside of Bowl, To Shape Interior of Bowl

Models: 4224B

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A 1/4" bowl gouge is best suited for smaller bowls and light finishing cuts. Larger 3/4" and 1" bowl gouges are only used for extremely large pieces.

Large domed scrapers can also be used to help clean up the interior surfaces of bowls. A light touch with the scraper slightly tilted will eliminate some of the ridges occasionally left by an inexperienced bowl gouge.

11.7Bowl Turning Techniques

11.7.1To Shape Outside of Bowl

1.Odd shaped burls, crotches and other irregular shaped blanks require special preparation before mounting in a chuck or onto a faceplate. Remove the bark, if there is any, from what appears to be the center of the top of the workpiece.

2.Drive spur center into the top of the workpiece with a mallet or dead blow hammer.

3.Slip the spur center into the headstock taper and bring the tailstock with a live or ball bearing center into position. Lock the tailstock to the bed and advance the tailstock spindle in order to seat the cup center into the workpiece. Tighten the ram locking handle.

4.Turn workpiece by hand to ensure proper clearance.

5.Start lathe at lowest speed and bring it up to the maximum safe speed for the size of work to be turned. If the machine starts to vibrate, lower the speed until vibration stops.

6.Rough out the outside of the bowl with the 1/2" deep fluted bowl gouge, holding the handle of the tool firmly against your hip. For best control, use your whole body to move the gouge through the workpiece.

7.As the bowl takes shape, work on the bottom (tailstock end) to accommodate attaching a face plate.

8.Turn a short tenon (about 1/8" long) the size of the hole in the faceplate. See Figure 44. This will allow centering the workpiece when the faceplate is attached.

(NOTE: If you plan to use a chuck, turn a tenon of the appropriate length and diameter to fit your chuck.)

9.Stop the lathe, remove workpiece and attach face plate or chuck (see section 11.6.1 "Mounting Stock").

The surfaces of faceplate and workpiece should mount flush to each other.

10.Finish turning the outside of bowl with 1/2" or 3/8" bowl gouge. Leave additional material at base of bowl for support while turning interior. This will be removed later.

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Figure 44

11.7.2To Shape Interior of Bowl

1.Stop lathe and move tailstock away. (You may want to remove the center from the tailstock to avoid bumping it with your elbow.)

2.Adjust tool support in front of the bowl just below centerline, at a right angle to the lathe ways.

3.Rotate workpiece by hand to check clearance.

4.Face off top of bowl by making a light shearing cut across the top of workpiece, from rim to center.

5.Place 1/2" bowl gouge on tool support at center of the workpiece with the flute facing top of bowl. The tool handle should be level and pointed toward the four o'clock position, as shown in Figure 45.

Figure 45

6.Use the left hand to control cutting edge of gouge, while right hand swings tool handle toward your body (Figure 45). The flute should start out facing top of workpiece, and rotate upward as it moves deeper into the bowl to maintain a clean even curve. As the tool goes deeper into the bowl, progressively work out toward the rim. It may be necessary to turn the tool support into the piece as you get deeper into the bowl.

(NOTE: Try to make one, very light continuous movement from the rim to the bottom of the bowl to ensure a clean, sweeping curve through the piece.

Should there be a few small ridges left, a light cut with a large domed scraper can even out the surface.)

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Powermatic 4224B operating instructions Bowl Turning Techniques, To Shape Outside of Bowl, To Shape Interior of Bowl