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HAND POSITIONS
When using any of the chisels, the hand takes a natural position
on the tool handle.This position may be near the middle of the
handle or towards the end, depending upon the amount of
leverage required. The position of the hand near the tool rest is
a matter of individual preference, but there are three generally
accepted positions, each best for certain types of operations.
Roughing
Off
Roughing off and other heavy work requires a firm grip and
solid positioning of the chisel against the rest. This is best
obtained by the tool-rest hand positioned illustrated. The wrist
is dropped down so that the heel of the hand below the little
finger acts as a sliding guide against the rest. The handle
hand controls chisel position.
Figure 38
MAKING
STANDARD
CUTS
THE ROUGHING-OFF
CUT
Reducing a square or odd shaped workpiece down to
a cylinder of approximate size for finish turning is called
"roughing-off". Faceplate turnings and large diameter spindles
should first be partly reduced by sawing, but small spindles
are easily turned down entirely with the large (3/4")gouge.
Figure 35 - Roughing
Finish Cutting
Finish cutting requires more control - with less force. Finish
cutting is better done with the palm of the tool rest hand
turned up. The wrist is still held down, and the side of the
index finger acts as a guide along the rest. In this position,
control of the chisel is shared by both hands. The fingers of
the tool-rest hand are free to assist in positioning the tool.
Figure 36 - Finish Cutting
Intricate
Cutting
Intricate, delicate cutting requires extreme control with practi-
cally no force. This is best accomplished by guiding the chisel
with the fingers of the tool-rest hand. The hand is held palm up
with the wrist high. The little finger is placed against the rest to
steady the hand. The chisel does not touch the rest and the
handle hand is completely secondary to the tool-rest hand.
NOTE: The first and second positions are equally good for
scraping operations, but the third position is practically never
used for scraping.
Figure 37
Cutting
to Depth
Many scraping operations and cutting to depth with the part-
ing tool can be easily accomplished with the one hand. The
chisel is grasped firmly with the index finger on top to press
it down against the rest. It is thrust straight into the work.
Holding the tool in this manner leaves the other hand free to
hold a pattern or calipers, etc., to check work in progress.
Figure 39
•
Start the first cut about 2" from tailstock end - then run it
toward the tailstock and off the end of the workpiece.
•
Next, start another cut 2" nearer the headstock - and run
it back towards the tailstock, to merge with the first cut.
•
Continue cutting in this manner until 2 to 4" from the head-
stock is left uncut. Reverse the direction of tool travel and
work one or two cuts in succession toward the headstock
and off this end of the workpiece.
•
Never start a cut directly at the end - if the chisel catches
the end, it will damage the workpiece.
•
Never take long cuts while corners remain on the work,
as this tends to tear long slivers from the corners.
• The first series of cuts should not be too deep. It is
better to partially reduce the work to a cylinder all along
its length. After that, start a second series of cuts to com-
plete reducing it to a cylinder.
•
Once a cylinder has been formed, step lathe up to
next faster speed. Further reductions in size can now be
accomplished
by cutting as deeply as desired at any spot
along the work. At this stage, long cuts can be made from
the center to either end.
•
Generally, roughing off is continued until the cylinder is
approximately 1/8"larger than the desired finished size.
•
Roundness can be tested by laying the gouge on top of
the work - it will not ride up and down when cylinder
is perfectly round.
Figure 40
First Cuts
Testing Roundness
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