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• Place s kew atright a ngles with thework axis, flatagainst the
surface, and well u pnear t hetop. T he extreme heel should
bejustinside t hepencil line thatmarks thetopofthebead.
• Now, d raw skew straight back while raising h andle s lowly -
until e dge oftheheel a tthepencil linestarts t ocut.
• Asedge begins t ocut,roll s kew inthedirection ofthevee
sothattheexact portion o ftheedge which started c utting
will t ravel ina 90 ° arcdown t obottom ofthevee.
• Upon r eaching bottom ofthe vee, theskew should beonedge.
• Reverse themovements
tocutside oftheadjacent bead.
_'
Swing T ool
Figure 45 - Cutting Beads
It is important that only the extreme heel should do the cut-
ting. This means that the bottom edge of the bevel next to the
vee must at all times be tangent to the arc of the bead being
formed.
Easier beads can be shaped with the spear point chisel.
•
Use pencil marks and sizing cuts as before.
•
Push the chisel straight into each cut and rotate horizontal-
ly to round off the adjacent edges. It must be moved slight-
ly in the direction of rotation at the same time to keep the
point from digging into the adjacent bead (See Figure 46).
B_evel
Tangent To Work
Start
Finish
Figure 46
CUTTING COVES (CONCAVES)
This is the most difficult single cut to master - but one of the
most important in good wood turning.
•
First, use pencil marks to indicate the edges.
•
Then, rough out the cove, to within about '/8" of the desired fin-
ished surface, by scraping with the gouge or round nose chis-
el. If the cove is to be very wide, sizing cuts can be made to
plot the roughing out. Once it is roughed out, the cove can be
finished in two cuts, one from each side to the bottom center.
•
At the start of either cut, gouge is held with handle high
and the two sides of blade held between the thumb and
forefinger of tool rest hand, just behind the bevel.
•
Position the fingers so that they are ready to roll the blade
into cove.
•
Hold blades so that bevel is at 90° angle to the work axis
with point touching the pencil line and pointed into work axis.
•
From this start, depress point slightly to start cut, then
continue to move point down in an arc toward the bottom
center cove - at the same time rolling chisel uniformly so
that, at the end of the cut, it will be flat at the bottom of
the cove. The object is to keep the extreme point of gouge
doing the cutting from start to finish. Reverse these move-
ments to cut the opposite side.
_Pencil Mark
e
Cutting Coves
Figure 47
Coves also can be scraped to finish using the round nose
chisel or a rattail file. These methods do not generally pro-
duce perfectly curved coves.
MAKING LONG CONVEX CUTS
•
First, turn work down to approximate size, using sizing
cuts (as required) to determine various diameters. Finish
cuts can then be made with either skew or gouge.
•
If the skew is used, the principles of the operation are the
same as those employed in cutting a bead - except that
the curve is longer and may be irregular. Use the extreme
heel throughout - start at longer end of curve (if curve is
irregular) and progress toward steeper end.
•
If gouge is used, make cut in the same direction. Start
with the handle well back of point - swinging handle in the
direction of tool travel to overtake the point, if necessary,
when the steep part of the curve is reached. Object is to
have the extreme point doing the cutting throughout with
the bevel as tangent to curve as possible.
Figure 48 - Chisel Inclined in Direction of Cut
MAKING LONG TAPER CUTS
Long taper cuts are made like long convex cuts, with the skew
or gouge. However, the angle between the cutting edge and
handle is kept constant during the entire cut. The handle is
not swung around.
•
Always cut downhill. Do not cut too deeply at the center
of the taper.
SPINDLE TURNINGS
PLOTTING THE SHAPE
Once the basic cuts have been mastered, you are ready to
turn out finished work.
• The first step is to prepare a plan for the proposed turning.
This can be laid out on a suitable sheet of paper. The
layout should be to full size.
Diameters
lY4"
2"
1W' 2W' 1W'19/16"21/,6"
13/4' ' 17/j' 1'1/16 '' 1"
_non
I ,_
141/4"
_,. I
Sizing Cuts
Figure 49
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