- 12 -
BASIC WOODTURNING
POSITIONING THE TOOL REST FOR
CIRCUMFERENCE TURNING
When turning, the object is to pierce the
outer surface of the wood to a desired depth,
then to hold the chisel steady with the bevel
edge parallel to the work circumference, so
that the chisel will peel off a shaving at this
desired depth. The only sure method of
holding the chisel steady is to rest the bevel
against the workpiece, the tool rest will act as
a fulcrum to support the chisel against the
downward force of the revolving workpiece.
Fig.24
.
If the tool rest is positioned too low, so that
the chisel bevel is held out from the
workpiece, (
Fig.25
) the cutting edge of the
chisel will continue to dig deeper into the
workpiece until the “bite” becomes so deep
that you have difficulty holding the chisel,
then the chisel will begin to bounce or
chatter against the workpiece.
If the tool rest is positioned too low, the chisel
will be held extremely high to position the
bevel of the chisel against the workpiece
(
Fig.26
) then the tool rest will lose its value as
a fulcrum and the downward force of the
revolving workpiece will kick the chisel back
and possibly out of your hands.
If the tool rest is positioned too high and the
chisel is correctly positioned for cutting it will
strike near the top of the workpiece where
the direction of the force exerted by the
workpiece is almost horizontal and will again
result in kickback.
Fig.27
.
Fig.24.
Fig.25.
Fig.26.
Fig.27.
