lustration: Fig. 21.]
This cut is continued from alternate side until the concave is nearly to
size. The cut should be tested with a templet before the finishing cut
is taken.
B-I--6-a. Convex Cuts
Rough out the stock between the beads with a parting tool.
Hold the edge of the gouge on the rest with the handle, parallel to the
bed of the lathe, to make the nose the cutting point.
Swing the handle to the left so that the grind will form a tangent to
the bead at its highest point.
The gouge is then forced into the stock and to the right; at the same
time the handle is swung to the right; keeping the grind tangent to the
bead at the point of contact. Fig. 22. This cut is continued until the
base of the bead is reached.
B-I--7-a. Combination Cuts
As in spindle turning, a combination exercise should be given at this
point to provide an opportunity for studying out the best methods of
working the various cuts just described into a finished product.
USE OF SCRAPING TOOLS
When scraping is to be employed, it should be done with only those tools
that are made for that purpose, i.e., Square Nose, Round Nose, Spear
Point, Right and Left Skew. The handling of these tools will be found
easy. The only point to remember is that they should be held flat on the
tool rest and parallel to the bed of the lathe when in use.
In general practice the ordinary skew chisel should not be used as a
scraping tool, for the cutting edge is not sharpened to withstand the
heavy strain required by such work. Should it be necessary, however, to
use a skew chisel as a scraper, the tool should be held so that the top
grind is parallel to the bed of the lathe while in use.
INTERNAL BORING
In roughing out the center for Napkin Rings, Jewel Boxes, etc., the
quickest method is to work it out with a small gouge.
Place the gouge on the rest parallel to the bed of the lathe, having the
point even with the center of the stock.
Force the gouge into the wood until a hole is bored to the depth
required. If the hole is deeper than 1", remove the tool often and clear
out the shavings in order not to burn the point.
In order to enlarge the hole to the proper size the point of the gouge
is pressed against the left side of the hole a little above the center
and a shearing cut is taken. To obviate the danger of the tool catching,
all cuts should start from the back of the hole and proceed toward the
front.
[Illustration: Fig. 2
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