10.4Stock Selection
Stock for spindles should be straight grained and free of checks, cracks, knots and other defects. It should be cut 1/8" to 1/4" larger than the finished diameter and may require additional length so the ends can be removed later. Larger stock should have the corners removed to produce an octagon making the piece easier to rough down to a cylinder.
1.With a combination square, or plastic center finder for round stock, locate and mark center on each end of the workpiece. Accuracy is not critical on full rounds but extremely important on stock where square sections are to remain. Put a dimple in the stock with an awl or nail, or use a
2.Extremely hard woods may require kerfs cut into the ends of the stock (Figure 23) using a band saw, so the wood will accept the spur center and the live center.
Figure 23
3.Drive the spur center about 1/4” into the workpiece, using a wood mallet or dead blow hammer as shown in Figure 24. Be careful that you do not split the workpiece.
Figure 24
Never use a steel face hammer and never drive the workpiece onto the spur center while it is mounted in the Lathe spindle.
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
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 rest 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 25. Tighten tool rest 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 25
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