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In this demonstration Rex showed us several techniques for adding interest to
woodturnings by embellishments such as texturing, beading, and dying. As a
general rule, texturing and coloring are not advisable where they would detract
from beautiful natural figure or color in the wood itself. Texturing is usually
most effective on smaller pieces. It tends to get lost on larger pieces. Rex
demonstrated several special purpose tools including the Joe Wagner Texturing
Tool, the Sorby Spiraling System, a bead cutting tool, burning wires, a
wood-burning pen, and the Proxxon mini-grinder with an ArborTech cutting wheel.
Joe Wagner Texturing Tool
This tool was invented by Joe Wagner, a member of the Timp Woodturners
Association. It uses a sharply knurled wheel to emboss a pattern into the wood.
Since this is a stamping action rather than a cutting action it requires
considerable pressure against the wood and takes some time to deepen the
pattern effectively. The tool is available in two widths (1/4 and 3/8 inch) and
two tooth sizes (12 and 16 TPI). The larger tooth is more effective with softer
woods and the smaller tooth with harder woods. Rex used box elder in this demo
to create a spinning top with texturing on the top and bottom surfaces as well
as the edge.
Rex trued up the bottom face of the top blank with a clean shearing cut then
applied the texturing tool to that end grain. The tool rest must be adjusted to
allow the wheel of the tool to contact the wood at center height. The wheel is
pressed squarely against the surface of the wood with considerable pressure
using a lathe speed of 400-500 rpm. The tool does not travel across the tool
rest, but a slight rocking motion from side to side helps deepen the texturing
pattern uniformly, especially if the wood surface is slightly convex. This tool
will not work with a concave surface. When turning against end grain, the track
of the outer edge of the wheel is at a larger diameter than the inner edge
giving an interesting difference in the texture pattern across the textured
area. The appearance of the embossed pattern will be affected by angle and
movement of the tool. Experimentation is the only way to discover and refine
those differences so don't be afraid to play around with options. In general,
texturing is most effective when done in bands. Rex showed us how to define and
differentiate those bands with colored markers. He used TomBo ABT double ended
markers that can be obtained at art supply stores.
After shaping the edge and the upper face of the spinning top, Rex used the
same Joe Wagner tool and technique to texture those surfaces as well. Bear in
mind that the pressure being applied to the wood during texturing demands that
the texturing be done while there is still adequate mass and rigidity in the
wood to support it.
Textured areas that have been colored with a marker can be buffed with paper
towel until no more color is being transferred to the towel and then top coated
with lacquer.
Beading
A bead-cutting tool is generally formed by machining a flute in the top face of
a square shaft. The end of the tool is ground square across with a fairly blunt
bevel (60+°) and the sides ground back to the edge of the flute. A
sharper angle grind on the tip will make deeper beads and a blunter angle will
make shallower beads. The tool can be applied in a scraping cut with the flute
up (very aggressive) or flute down. Rex used the flute-down approach in this
demo. Since this is basically a scraping cut it is wise to choose woods that
scrape well and cleanly. Apricot is quite good. A single bead is formed when
the tool is applied squarely to the surface being cut. A slight rocking motion
side to side will make the bead slightly smaller, but cleaner. A uniform series
of beads can be cut by successively placing one edge of the flute to track in
the groove of the preceding bead as a guide. These beads can be cut on both the
interior and exterior surfaces of a bowl. It is usually wise to relieve the
outer beads in a series so they stand proud of the rest of the surface of the
piece.
Many options are possible when using embellishing beads. The grooves between
beads can be friction darkened with burning wires, or with a thin strip of hard
material such as Formica -type laminate or thin cardboard such as that used in
soft drink cartons. The beads can be segmented with a wood burner. Segmenting
lines can be drawn across the series of beads using the tool rest as a straight
edge and indexing the rotation of the turned object on the lathe to regulate
the spacing. If the tool rest is aligned right on center the lines across the
beads will be radial. If the tool rest is aligned below center the lines will
form a spiral ray. Once the lines are drawn with pencil they can be burned with
a wood-burning pen. Segments thus defined can then be colored in interesting
patterns using marking pens. The burned lines help prevent color bleed between
segments. If an entire bead is to be colored, dyes can be applied with a Q-tip
while using a piece of metal foil as a mask held edge-wise in the groove
between beads to protect against accidental contact with the adjacent bead as
the lathe turns very slowly. It is wise to use vinyl gloves whenever working
with dyes. When planning to use coloring it is best to choose woods that are
light in color and have tight and even grain. Holly and maple are good
examples.
An alternative to cutting a series of fine beads is to use a male threading
tool to cut evenly spaced grooves. This is easily done by holding the tool
squarely against the surface of a rotating piece without allowing the tool to
travel across the tool rest. The grooves can then be darkened with a burning
wire.
Sorby Spiraling System
This tool provides a cutting rather than stamping action. It consists of a
freely turning toothed rowel mounted in a sturdy shaft. When held against the
surface of wood turning in a lathe, the rowel is forced to turn and the teeth
cut a spiral pattern into the wood. The tool rest must be set so the rowel
contacts the wood at center height. The tool can be moved repeatedly in either
direction across the tool rest to establish the depth and width of cut desired.
The cut should progress until the tooth of the spiral is sharp. Going any
deeper provides no benefit. The pitch of the spiral is determined by the angle
at which the rowel contacts the turning circle. An auxiliary tool rest provided
with the system can be clamped to the shaft of the tool to set a fixed angle of
contact. Reversing the angle of the auxiliary tool rest reverses the direction
of the cut so a right-hand cut can be combined with a left-hand cut to form
crossing spirals and produce diamond shaped knurling. The set angles must be
exactly the same in each direction. As with a series of beads, the edges of the
spiral band should be defined with a relief cut.
Proxxon Power Cutter
This technique involves using a rotating cutter wheel moved back and forth
across a rotating piece. The cutter essentially cuts intermittent gouges out of
the surface of the rotating wood. The lathe speed, cutter speed, travel speed,
and cutter angle all influence the resulting texture pattern. The textured area
can be cleaned up with a nylon brush. In this demonstration, Rex dyed the
textured area and ebonized it by burning off the dye solvent with a torch. He
then power sanded the textured area with 180-grit abrasive to create a mottled
appearance where the high points of the texturing were sanded bare. He also
suggested that a complementary dye could be applied to color the exposed areas
and provide interesting contrasting color patterns. The dyed areas could then
be over-sprayed with lacquer.
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