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Spiral Layouts—Three Ways
version in pdf format
The traditional way to lay out spirals leaves me cold—for a
simple spiral on small work with 5 full turns you would need 4 longitudinal
lines, dealing with parallax error scribing from the tool rest, and 21 or so
circumferential lines and then you need to figure where you are in that visual
mess. This article is about three different ways to lay out spirals for wire
inlay on small work, although they can be adapted for other spiral uses. The
first uses a simple to make layout tool to plot a series of dots with virtually
no parallax error. The second uses masking tape wrapped around the work that the
lines are drawn on when the tape is off the turning. And the third uses the
resizing ease of CAD programs to layout the cutting lines on paper which is
temporarily glued to the work. Why three ways?
Well the first way is about the only way to handle spirals on a
non-cylindrical turning and not everyone has discovered the usefulness of a CAD
Connect the Dots
Begin by making the layout tool. To do that you need to
know how big an area you want the spiral to be in, so make a couple of V-cuts in
the turning at the ends of the area where the intended spiral, as in
Fig01. Cut a rectangle of sheet metal (aluminum
flashing, for instance) about an inch wider than the spiral area and 4 or so
inches long. Put a piece of masking tape (it’s easier to draw on) across the
rectangle about ¾” from one end. Arrange your tool rest an inch or so away from
the center line. Now lay the rectangle across the turning and your tool rest so
that the end of the rectangle lines along the center line on top of the turning.
Make a mark with a pencil where the rectangle intersects the back edge of the
tool rest as in Fig02.
spindle with the intended extents of a spiral marked with V-cuts.
the location of the first bend on the layout tool. The back edge is centered on
the top of the spindle, and a mark is made where the layout tool goes over the
back edge of the tool rest.
Remove the rectangle from the lathe. Use a square to draw a
line across the rectangle at the mark. Then draw two more lines across the
rectangle that are ¾” and 1-1/2” below the first line respectively as in
Fig03. A metal vise makes a good break to bend
sheet metal, but you can use any straight edge with care. Insert the rectangle
in the vise so that middle line is at the top edge of the vise jaws. Bend the
rectangle as far as it will go away from the tape as in
Fig04. Remove the rectangle from the vise and continue the bend so that
the metal is almost folded over. Reinsert the metal in the vise and close the
jaws to complete the bend. Readjust the metal so that the first and third lines
are even with the top edges of the front and back jaws respectively as in
Fig05. Bend the metal to 90 degrees to front and
back respectively as in Fig06. The completed
layout tool, now in a squashed “T” shape, is seen from the bottom in
completed bending layout on the layout tool.
making the first bend of the layout tool.
set-up for making the second bend of the layout tool.
making the second bend of the layout tool.
completed layout tool from the bottom.
Connect the Dots
Place the layout tool across the tool rest so the bottom
tab is against the back edge of the tool rest. Move the tool rest so that the
back edge of the layout tool is on the top center line of the turning as in
Fig08. Put masking tape even with the back edge
of the layout tool, then mark the extents of the spiral area on the tape as in
Fig09. Now you need something with a straight
edge you can temporarily attach the tape to without losing adhesive that you can
also draw on. I used a square of melamine.
Adjusting the tool rest so that the back edge of the layout tool is centered on
the top of the spindle when the bottom tab is against the back edge of the tool
the spiral extents on tape attached to the layout tool.
Transfer the tape so that the marked edge lines up with the
straight edge. Use a square to draw a line perpendicular to the straight edge at
the right hand mark as in Fig10. Decide how many
turns you want your spiral to make. Arrange a ruler so that an inch mark is on
the left hand mark, and as many inches away as you want turns is on the
perpendicular line as in Fig11. In the example I
wanted five turns. The 11” ruler mark is on the left hand tape mark, and the 6”
ruler mark is on the vertical line. This is how flat woodworkers layout hand
dovetails. Draw a line along the ruler. Make a tick mark at each inch. These
marks will indicate the spiral intervals—call them interval marks. Now make a
tick mark at each ¼” for the first inch. These marks will indicate where to
register the spiral intervals at spindle rotations 90 degrees apart—call them
registration marks. Use a square to draw lines from each tick mark down to the
bottom of the tape as in Fig12.
Fig13 shows the completely marked tape.
transferring the tape to a work surface and drawing a line perpendicular to the
right extent mark.
a diagonal line to divide the spiral area into equal segments.
Extending the marks on the diagonal line down to the tape to mark the segments.
Transfer the tape back to the layout tool. What had been on
the bottom when laying out the tape should be on the back edge of the layout
tool, with the one quarter rotation marks at the left. (if you did it backwards,
it’s not a big deal—just rotate the spindle the other way when changing
intervals). Engage your lathe index at the zero position and place the layout
tool in position. The back edge of the layout tool should be centered on the top
of the spindle, and the tab should be against the back of the tool rest. Center
the layout tool on the spiral extents (the first and last marks should be on the
left and right V-grooves, respectively. Make a dot at each interval mark,
including the ends as in the top image of Fig14.
the layout tool to layout dots on the spindle in four steps.
Readjust your lathe index so that the top of the spindle
has rotated one quarter of a turn away from you. Slide the layout tool to the
right so that the rightmost registration mark is even with the right hand
V-groove. Make a dot at each interval mark that is in between the V-Grooves as
in the 2nd from the top image of Fig14.
Readjust your lathe index so that the spindle has rotated
another quarter turn (now 180 degrees from the original orientation) away from
you. Slide the layout tool to the right so that the middle registration mark is
even with the right hand V-Groove. Make a dot at each interval mark in between
the V-Grooves as in the 3rd from the top image of
Readjust your lathe index so that the spindle has rotated
another quarter turn (now 270 degrees total). Slide the layout tool to the right
so that the left most registration mark is even with the V-Groove. Make a dot at
each interval mark in between the V-Grooves as in Fig14.
Now draw lines to connect the dots as in Fig15.
You’ll have a nice visually clean line to follow when sawing the spiral.
spindle after connecting the dots. This yields a nice, clean, easy to follow
Saw and Wind
Unlock the lathe indexing mechanism. Now use a saw to cut a
groove following the line. You can use a mini-hacksaw, a mini-hacksaw blade
mounted to aluminum bar to give an automatic depth stop, or a metal jigsaw blade
mounted in a fret saw blade as in Fig16. Other
than using a fine tooth blade you can use whatever saw suits the width cut you
want and what you have on hand. Turn the lathe by hand as you saw, concentrating
on following the line (you’ll need to keep the saw at a constant angle to do
this) and keeping the saw from jumping out of the kerf due to sloppy or too
vigorous strokes. When the sawing is complete use a drill to drill a hole where
the spiral intersects the V-Groove at both ends of the spiral as in
Fig17. Suit the drill bit size to the wire you’re
using. Take care to keep the drill vertical so the exit hole is in the V-groove
as well. A power drill is fine, I just keep a size drill bit in that cute little
yankee-drill that’s works for most wire I use—it’s kept handy with my wire
the spiral with a fret saw. Any fine tooth blade will do.
a hole at the intersection of the spiral and V-groove.
Start the wire-wrapping by making a right angle bend in the
wire with needle nose pliers as in Fig18. Insert
the wire into the left hand hole so that the bend is flush with the hole
opening, then start winding on the wire by turning the spindle by hand. Make one
turn into the V-Groove, then start into the spiral. Maintain tension the whole
time. When you get to the end of the spiral you have to maintain tension with a
finger slightly before the end of the spiral, wrap the wire around the spindle
loosely and then through the hole as in Fig19, so
that you have a turn in the V-groove. Then snug up the wire and cut the excess
flush with diagonal cutters. The finished
wire inlay is shown in Fig20.
the wire inlay by making a right angle bend in the wire and inserting it in the
hole at the intersection of the V-groove and spiral.
Finishing winding on the wire inlay. My left index finger is maintaining tension
on the wire while the end of the wire is looped around the spindle and through
completed spiral wire inlay.
To layout a crossed spiral, plot dots at both the 1st
and 3rd register marks when the spindle is rotated at both 90 and 270
degrees. For curved surfaces, simply press the layout tool down to fit the
curve. Fig21 shows an example of a crossed spiral
on a curved surface.
example of a crossed spiral on a curved spindle.
Spirals can be complicated curves to draw in three
dimensions, but conveniently if the 3D cylindrical surface is unrolled into a
flat two dimensional surface, they become straight lines. You can do this trick
with some extended release masking tape. It’s easier to see pencil lines on
green tape than on blue. You’ll need tape that is somewhat wider than the
circumference of your spindle.
Begin by cutting a piece of tape slightly longer than the
extents of your spiral. Make a fold about ¼” from one side. Stick the tape on
the spindle with the ¼” fold folded back as in Fig22.
Wind the tape around the spindle and end by overlapping the folded back portion
to create a tab as in Fig23. Mark the extents of
the spiral on the tape. Now cut off the tab with a knife while maintaining
moderate tension with your other hand as in Fig24.
If you’re careful you’ll end up with tape that wraps almost exactly around the
spindle as in Fig25.
to apply masking tape. The edge was folded back before attaching to the spindle.
wrapping the tape around the spindle forming a tab, and marking the spiral
extents on the tape.
off the tape tab to leave tape almost exactly wrapped around the spindle.
cutting off the tape tab.
Remove the tape from the spindle and transfer it to a
smooth surface with a straight edge, such as a square of melamine. Use a square
to draw a line perpendicular to the tape at the right hand extent mark as in
Fig26. As before, use a ruler to divide the
spiral area into the number of equal segments you want, as in
Fig27. If you want a single spiral, simply draw
lines from the top of one segment division to the bottom of the next as in
Fig28. I used a ultra-fine point marker to make
these lines stand out. If you want a crossed spiral, also draw lines from the
bottom of one segment division to the top of the next, as in
Fig29. You will only need to drill one hole in
the spindle for a crossed spiral.
Fig26: The tape
after transferring to a work surface and drawing on a perpendicular line at the
right extent mark.
dividing the tape between the extent marks into equal segments.
drawing diagonal lines through the segments. This will yield a single spiral.
drawing diagonal lines the other way through the segments. This will yield a
Transfer the tape back to the spindle, being careful to
line up properly with the extents as in Fig30.
Saw and wind on wire as before. The finished cross spiral example is shown in
moving the tape back on to the spindle.
completed crossed spiral.
If you have a CAD program (or
with a little more trouble, any program capable of image resizing) you can use
it to lay out a spiral pattern. The great advantage is you only have to do the
work of drafting the layout once, and then can easily resize it to fit a new
spindle with minimal further work. It’s also fairly easy to do more complicated
layouts such as graduated spirals, or spiraling groups of lines, or any other
thing you can think up. To use CAD drawings, you simply prepare a stock layout
that has the number of turns and pattern that you want. Then measure the
dimensions (diameter and length) of the spindle area to be spiraled, and change
the dimensions of the pattern to suit, print it out, and glue it on.
Begin by measuring and writing down the length of the
spiral area as in Fig32, to get the required
length of your pattern. Then wrap a sample of your printer paper around the
spindle and measure the diameter of the spindle plus two paper thicknesses as in
Fig33. It’s easier to do the math if you use a
caliper that measure in hundredths of an inch, or in millimeters if you’re
feeling European. Multiply the diameter by pi (3.12) to get the required height
of your pattern.
Measuring the length of the spiral area with a dial caliper.
Measuring the diameter of the spindle plus paper with a dial caliper.
Fig34 shows a typical spiral
pattern in a CAD layout. This one is for a crossed spiral with four turns. By
simply selecting the pattern in the TurboCAD program, and tabbing down to the
dimensions boxes at the bottom of the window the length and height of the
pattern can be changed to the dimensions required. The way CAD programs work
varies, so you’ll have to learn how to do it in the one you have. It would be
possible, if you have a suitable drawing in digital form to change the
dimensions with any photo editing software. You would need to crop the picture
to the edges of the pattern, and then change what is usually called the canvas
size. You’ll need to uncheck what is usually called restrain proportions.
the dimensions of the spiral pattern to suit the spindle in a CAD program.
After changing the dimensions of the pattern to your
spindle, print out the pattern. Cut out the pattern and try it on the spindle
for size as in Fig35. If it’s off too much,
simply adjust the dimensions and try again. Once you’re satisfied with the fit,
apply some adhesive to the pattern. Post-it note glue will work, but spray
adhesive such as 3M #77 gives a more secure hold but can still be easily removed
with some mineral spirits. Fig36 shows applying
some spray adhesive to the back of the pattern. Newspaper absorbs the over
spray, and a bamboo skewer keeps the spray from making the light pattern blow
the fit of the pattern. This one is a little small so I printed out another with
a slightly larger height.
spray adhesive. Newspaper takes the over spray and a bamboo skew keeps the
pattern from blowing away.
Attach the pattern to the spindle as in
Fig37. As you now have nice thin black lines on a
white background to follow, it should be easy to stay on the pattern when sawing
(it’s easier to follow a line you can actually see). After sawing the pattern,
saturate the paper with a paper towel dipped in mineral spirits as in
Fig38 and give it a minute or so to soak in. The
pattern should come off easily. Use the paper towel and mineral spirits on the
wood to remove any residual glue and then sand and wind on your wire. A
completed spiral, this one a graduated crossed spiral, is shown in
attaching the pattern to the spindle.
the pattern after sawing by applying mineral spirits.
crossed spiral with graduated segments. This would be difficult to lay out using
traditional techniques, but is easy with a CAD program.
If you want to be able to see more clearly what your saw is
doing to the wood and don’t want paper/adhesive/sawdust clogging the kerf, you
could try heat transferring the pattern to the wood. This will only work for
light colored woods such as maple. Tape the pattern in place with the pattern
facing in. Mostly put the tape on the ends, but you’ll have to use some on the
seam to keep it closed. Then iron over the pattern with a hot iron long enough
to transfer the pattern to the wood. I had moderate success with this—I had to
pencil in a few missed areas.
At first a pen seems to be an obvious application for a
wire spiral inlay—but what about drilling through the bushings and dodging the
pen works with the wire? One way to
avoid this problem is to use something other than wire. A single tube design,
such as Penn State Industries CEO design makes sense for a spiral design.
Whatever kit you pick, make sure the wood can be left thick enough that you
won’t cut down to the tube when you saw the spiral as that would be expecting
miracles from your glue.
Before you begin turning the pen harvest some contrasting
sawdust. One way to do this is to chuck up a small spindle in your lathe, place
a sheet of paper under the wood, and turn on the lathe at a SLOW speed and your
dust collector off. Sand with 100 grit or so, with the sandpaper stretched over
the top of the spindle until you’ve got enough and then some.
Mount the pen blank and turn it a trifle oversize. Apply a
coat of sanding sealer so that the sawdust won’t get into the pores where you
don’t want it. Cut the spiral with what ever pattern method you favor. Mix the
sawdust with a binder (I used lacquer sanding sealer) and work it into the saw
kerf with your fingers. Don’t worry overly about the excess on top. Then give
the binder a chance to cure.
After the binder is well cured, skim the pen surface with
your skew. This will remove most of the excess sawdust on top as well as stray
wood fibers left at the top of the kerf. You can sand longer if you don’t have
skew confidence, but it’ll clog up quickly at first. Then sand, finish, and
polish the pen as you usually do. The result is shown in the front of
It is possible to use wire inlay with a single tube design.
Use a crossed spiral design which only requires one hole and plan for the hole
to be at the pen tip end of the tube. Use an adjustable length mandrel (I used a
size D drill blank in a collet chuck) with the tailstock holding the second
bushing in place. Turn the pen blank normally, being sure to design it so that
the wood is thick enough that you won’t saw down to the tube. Use whatever
layout method you like and saw the spiral.
Remove the bushing at the tailstock end, shorten the
mandrel, and hold the pen tube in place with just the tailstock. Drill through
one side of the wood and pen tube where the spirals intersect the end V-cut as
in Fig40. Don’t try to drill through both sides,
as with a hollow tube you’re not likely to hit the V-cut on the opposite side.
Instead, turn the pen blank 180° and drill through wood and tube at the V-cut
opposite the other hole. Sand the pen but don’t apply finish yet.
for inlay wire with the bushing removed.
You won’t be able to maintain tension on the wire and
thread the wire through the second hole, so before you start winding the wire on
make a loop out of scrap wire. With the tailstock backed out so you can see,
thread the free ends of the loop through both holes. Make a right angle bend
about an inch from the end of the inlay wire and thread the bent end of the
inlay wire through both holes as in Fig41. Bend
the free ends of the loop and inlay wire out of the way towards the tailstock
end and replace the tailstock.
threading a loop of scrap wire and the end of the inlay wire through both holes.
Wind on the inlay wire maintaining tension. When you get to
the end of the pattern, slip the end of the inlay wire through the loop, then
grab the free ends of the loop with pliers and pull the loop through the hole
thus pulling the inlay wire through. Trim the free ends of the inlay wire flush
with the pen tube, and then apply finish as normal. Before assembly, push on the
wires crossing the tube at the free end hole side to pull them out of the hole.
The ferule should easily push over the wire now. The finished pen is shown in
the back of Fig42.
finished pens. The front pen is Holly with Rosewood sawdust infill. The back pen
is Blue Mahoe with brass wire inlay.
Tools and Materials
Fret Saw or Mini-Hacksaw
Needle Nose Pliers
Connect the Dots
Aluminum flashing or other sheet metal
David Reed Smith is a basement woodturner living in Hampstead, Maryland. He welcomes questions, comments, and
suggestions by email at
David@DavidReedSmith.com. This article, along with about 50 others, is
available on his web site at