Powermatic 4224B operating instructions Cutting Techniques, Roughing Out

Models: 4224B

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Figure 38

4.Make sure headstock is locked to lathe bed.

5.Clean tapered end of spur center and inside of headstock spindle.

6.Insert tapered end of spur center (with the attached workpiece) into headstock spindle.

7.Support the workpiece while bringing the tailstock into position about 1-inch away from end of workpiece. Lock tailstock to bed.

8.Advance tailstock quill with the handwheel in order to seat the live center into the workpiece. Use enough pressure to secure the workpiece between the centers so that it won’t fly off, but do not use excessive pressure.

9.Tighten quill locking handle.

The tailstock quill is capable of exerting excessive pressure against the workpiece and the headstock. Apply only sufficient force with tailstock to hold workpiece securely in place. Excessive pressure can overheat center bearings and damage both workpiece and lathe.

10.Move tool support into position. It should be parallel to workpiece, just below the centerline and approximately 1/8" to 1/4" from the corners of the workpiece to be turned, as in Figure 39. Tighten support base to Lathe bed.

11.Rotate workpiece by hand to check for proper clearance.

12.Start lathe at lowest speed and bring it up to the appropriate RPM for the size of workpiece used. Consult digital readout on the headstock.

Figure 39

11.5Cutting Techniques

11.5.1Roughing Out

1.Begin with a large roughing gouge. Place the tool on the tool support with the heel of the tool on the surface to be cut.

2.Slowly and gently raise tool handle until cutting edge comes into contact with the workpiece.

3.Beginning about 2” from the tailstock end of the workpiece, roll the flute (hollowed-out portion) of the tool in the direction of the cut. See Figure 40. Make long sweeping cuts in a continuous motion to rough the piece down to a cylinder.

4.Keep as much of the bevel of the tool as possible in contact with the workpiece to ensure control and avoid catches. NOTE: Always cut down-hill, or from large diameter to small diameter. Always work toward the end of a work-piece, never start cutting at the end.

Figure 40

5.Once the workpiece is roughed down to a cylinder, smooth it with a large skew. Keep the skew handle perpendicular to the spindle and use only the center third of the cutting edge for a long smoothing cut (touching one of the points of the skew to the spinning workpiece may cause a catch and ruin the workpiece).

6.Add details to the workpiece with skew, parting tool, scraper or spindle gouge.

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Powermatic 4224B operating instructions Cutting Techniques, Roughing Out