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Fig. 25A
Steady
(_ Im/a i
Thrust
"_'_
Against
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Bevel
Hands
_._"'_/
Against
Chisel Cutting Properly
Fig. 25B
No Support
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r,
Chatter
! ;,"
Pgi/t
o Lo
Chisel Too Horizontal
Fig. 25C
Kickback
Rest
Too Low
Chisel
Too High
Fig. 25D
Kickback
__
.
Chisel
Rest
Too High
On Work
Fig. 25E
Handle 0d_'./
Fig. 25F
Rest Too Distant - Chisel Too High
Point Too Far From Rest
_
Sti_leter
Figure 25
If the rest is placed too high (Figure 25D) and the chisel is
correctly positioned for cutting, it strikes the workpiece near
the top where the direction of force exerted by the workpiece
is nearly horizontal - and kickback will again result.
If the rest is placed too far out from the work surface
(Figure 25E), then, when correctly held, the chisel is again
too high on the work. Also, you have less leverage on your
side of the tool rest and it is even more difficult to hold the
chisel. With large diameter work (Figure 25F), the tool rest
can be above the workpiece centerline, and somewhat out
from the work surface. With small diameter work (Figure
25G), the rest should be closer to the work surface. As
work grows smaller, the rest should be repositioned.
How to Position Tool Rest for Circumference
Scraping
In scraping operations, the tool rest position is not as critical
as it is for cutting operations.
•
The chisel generally is held horizontally, though it can be
held at an angle to reach into tight places. Considering that
the wire edge of the chisel does the scraping, Figures 26B
and 26C show the results of too low or too high a position
for the rest.
•
Figure 26A shows the chisel action with the rest correctly
positioned.
Fig. 26A
Fig. 26B
Fig. 260
.;
Edge
N_
....
Digging
In
Correct
Figure 26
How to Position Chisel and Rest for Diameter Scraping
When scraping on the diameter, that portion of surface to the
right of center is moving upward (Figure 27A). If a chisel is
placed in this area, it will simply be carried up off the rest
and out of your hands.
•
All diameter approach operations must be done at the left
of center.
Three different chisel contact points are shown in Figure 27B.
It will be noted that when a chisel is above the workpiece cen-
ter (or below it) the work surface sweeps past the chisel edge
at an angle and tends to carry the chisel in one direction or
the other along the rest.
•
Only when the chisel contacts the work on the centerline,
does the work surface pass squarely under the chisel
edge. This, then, is the position in which it is easiest to
hold the chisel steady. To obtain this position, place the
rest approximately 1/8"(thickness of chisel) below center.
Fig. 27A
es@
Fig. 27B
U___
Figure 27
USING THE GOUGE
Three gouges, the
1/4,
1/2 and 8/4"sizes, are adequate for
general homeshop turning. Other sizes from 1/8 to 2" can
be purchased to provide more flexibility.
The chief use of the gouge is for rough circumference
cutting
of raw stock down to a cylinder of working size. It is best to
use this tool for rapid cutting away of large areas of the work-
piece. When the tool is used this way, it does not produce a
smooth surface. With practice, the gouge can be used for
cutting coves and the shaping of long cuts.
Cutting Edge
Advanced
Wrong
Right
Figure 28
When used for cutting, the gouge is always held with the con-
vex side down. It should be rolled approximately 30 ° to 45° in
the direction in which it is being advanced along the rest and
the cutting edge should be slightly ahead of the handle.
USING THE SKEW
• Two skews, the 1/2and 1" sizes, are all that are needed
for general use. Other sizes are available.
This tool is nearly always used to make finished cuts, to cut vees
and beads, and to square shoulders. Properly used, it produces
the best finish that can be obtained with a chisel. It is not recom-
mended for scraping because the edge tends to dull more quickly.
•
For finish cutting, the skew is held with the cutting edge
considerably in advance of the handle, bevel side down.
Keep the base of the bevel against the work. It is good
practice is to place the skew well over the work, pull it
back until the edge begins to cut, then swing the handle
into position to advance the cut.
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