If the workpiece is to be shaped all around the perimeter, hold it firmly and push the work straight into the cutter until the depth of cut is established by the collar as shown in Figure 39. Continue to feed the work so that the point of contact on the edge is always 90 degrees to the collar (or directly in line with the cutter edge) and held firmly against it.
When the workpiece is not contoured all around, start the cut as shown in Figure 45. With this operation, the workpiece is positioned against the starter pin and the end swung into place to start the cut. When the cut has begun and the workpiece firmly against the collar, swing the stock away from the pin and proceed with cut.
Freehand shaping is extremely dangerous. The operator must be aware at all times of the proximity of his hands to the cutter. Hands must never come closer than 12 inches to the cutter without the proper guard or similar safety device over the cutterhead.
Shaping With Collars
When shaping with collars and starting pin, always adhere to the following rules for good work and safe operation:
The collar must have sufficient bearing surface, as shown in Figure 40. Also, the stock must be fairly heavy in proportion to the cut being made. Under no circumstances should a short, light workpiece be shaped against the collars, as in Figure 41.
Note: The edge of the work to be shaped must be smooth. Any irregularity on the surface which rides against the collar will be duplicated on the molded surface.
Collars must be smooth and free from pitch and other substances.
Position of Collars
Collars may be used above, below or between cutterheads.
1.When the collar is used below the cutter, as shown in Figure 42, the progress of the cut can be seen throughout the operation. However, any accidental lifting of the work will gouge the wood and ruin the workpiece.
2.When the collar is used above the cutter, as shown in Figure 43, the cut cannot be seen. But this method offers an advantage in that the cut is not affected by slight variations in the thickness of the stock. Also, accidental lifting of the workpiece will not gouge the workpiece; simply repeat the operation to correct the mistake.
Figure 39
Figure 40
Figure 41
Figure 42
Figure 43
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