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If you would like to be notified when I post a new article, send me an email. I'll only use the list for that purpose, and I'll mail blind cc so your address won't be any the worse for spam. This article was published in the July 2016 edition of More Woodturning Hemispherical Ornament Stand as 4 page pdf
Hemispherical Ornament Stand
Introduction
Just because they’re often called tree ornaments doesn’t
mean they can only be hung on a tree.
For instance, I habitually give ornaments to friends and family, and some
of the older ones don’t put up a tree any more.
If there’s an ornament you’re particularly proud of you might want to
keep it out year round. If there’s
an ornament you’re not so proud of you might want to keep it out where you can
see it to remind yourself to work on improving it. This article shows how to make a hemispherical ornament
stand. It’s got a fair amount of
heft to it so you won’t have to add weights for stability.
It has a simple design so as to not compete with your ornament.
You can cut and even finish the base before it’s turned round for
convenience and safety. And you get
to make two at once. Briefly a turning square is cut on a 45 degree angle and
then reassembled with a reinforced temporary joint.
It’s turned into a sphere using the shadow method (or whatever method you
prefer) with finials at each end.
Wire is twisted together to make the hanger and inserted in holes drilled in the
finials. Preparing the Blank
Start by cutting a 5” long piece of nominally 3” x 3”
turning square. Three inch turning
stock can be hard to come by, and it doesn’t matter for the design if it’s a
little undersize. For instance, the
blank I’m using for the photos is 2-3/4” square Apple.
Find the mid-point of a face of the blank and draw a 45° line through it
as in Figure #1.
Figure #1:
Draw a 45° line through the mid-point of the blank. Cut the blank in two on the 45° line.
A table saw cut results in the nicest surface, but if you use a bandsaw
you’ll just have to sand a little longer.
Finish the cut surface (which will be the bottom of the ornament stand)
to your satisfaction at this point.
Obviously, from the next photo, I was over easily satisfied.
Cut a 1” or so piece of a sturdy nail or dowel.
Tailstock pressure exerts a lot of shear
force on what will be the temporary joint.
The nail or dowel keeps this force from breaking the temporary joint.
If you do want to add weight to your ornament stand, drill a hole large
enough for the weight, such as lead fishing sinkers, and choose a dowel to
match. Find the mid-point of both
cut faces and drill a somewhat loose hole for the nail at both mid-points as in
Figure #2.
Figure #2:
Drill holes for a temporary joint reinforcing pin at the
mid-point of both diagonal faces. To create the temporary joint, cover both diagonal faces in
original blue masking tape (not edge lock).
If you used a bandsaw for the diagonal cut and did not sand it smooth use
“rough surface” masking tape.
Lightly sand the masking tape to remove the surface coating for better glue
adhesion. Cut a piece of poster
board (or cereal box cardboard if you sand off most of the printing) the size of
the diagonal face and poke a hole through it for the dowel or nail.
Apply a thin coat of wood glue (or dot with Ca glue if you’re in a hurry)
to both taped surfaces. Then
assemble the temporary joint with the poster board in between the taped
surfaces. This type of temporary
joint is as strong as a traditional Kraft paper joint but requires almost no
clean up. Clamp the joint together
until the glue cures as in Figure #4.
Figure #3: Create
the temporary joint with blue tape and poster board.
Figure #4:
Clamp the temporary joint until cured. Turn the Sphere
After the temporary joint glue cures, mount the blank
between centers. Turn the blank into
a cylinder as in Figure #5.
Figure #5:
Turn the blank round. Print out the shadow sphere pattern in Drawing A.
It will more dependably print true to size if you download the pdf from
http://davidreedsmith.com/articles/hemisphericalornamentstand/drawingA.pdf.
The pattern will lay flatter if you attach it to poster board or other
thin substrate with spray adhesive or a glue stick.
Drawing A:
The Shadow Sphere Pattern. Set up the Shadow Sphere Jig as in Figure #6.
See references for how to build one.
Mark the center of the blank so that you can line up the center of the
blank with the center of the pattern.
Adjust the height of the light and the platform so that the shadow of the
cylinder matches the diameter of the pattern.
Figure #6:
Set-up the Shadow Sphere Jig. If you choose to use another method to turn the sphere,
then I suggest that you first mark the center of the blank.
Measure the diameter of the cylinder, and mark the centered diameter on
the cylinder. Make parting tool cuts
to define the diameter to the size of the finials—about 1”.
Then turn to a sphere using the method you prefer. Start turning the
square by cutting diagonally at one end until the shadow of the cut is
tangential to the circle of the pattern ending at the cylinder for the finial
with a spindle gouge as in Figure #7.
Then round over until the shadow matches the pattern circle as in Figure
#8. A light cut with a shear scraper
such as a pyramid point tool will reduce sanding time.
Then repeat for the other half of the sphere as in Figure #9.
Fine tune the quirks at the junction of the sphere and finial.
Figure #7:
Cut a diagonal tangential to the pattern circle.
Figure #8:
Turn a half sphere.
Figure #9:
Turn the other half sphere. Turn the Finials
You can use the shadow method to turn the finials, but
there’s no particular advantage in doing so.
Measure out and mark 1” from the sphere at both ends.
Make parting tool cuts just outside the marks to a diameter of 3/8” as in
Figure #10. Then turn half-coves at
both ends as in Figure #11.
Figure #10:
Define the finial end location and diameter with parting tool
cuts.
Figure #11:
Turn the half-coves. Sand the sphere and half-coves.
If you want to use friction polish do that now as in Figure #12.
If you have a suitable sphere chuck and want to use it to remove the nubs
and drill for the hanger wire, then remove the turning from between centers.
If not, the reduce the nubs, remove from the lathe, saw them off by hand,
and sand the ends.
Figure #12:
Sand and optionally polish the turning. Before you can drill a hole for the wire hanger you have to
know what size hole to drill. So
make a small sample to test with.
Bend a piece of 3/8” rod into an ell shape and chuck it in a drill.
Double over a 6” or so length of 14-gauge copper wire (or whatever wire
you wish to use) and clamp the ends in a vise.
Use the ell in the drill to twist the wire into a spiral.
Measure the diameter of the wire and select a drill that is that
diameter. Make a test hole in end
grain and check the fit as in Figure #13.
Adjust if necessary.
Figure #13:
Check the fit of spiraled wire in the selected hole size. Insert the sphere in the sphere chuck (see references) and
use the tailstock center to center the finial.
Secure the sphere with blue masking tape as in Figure #14.
You may have to reduce the size of the nub on the other end so that it
will fit in the end of the lathe spindle.
Figure #14:
Mount the sphere in a sphere chuck. Part off the nub and dimple the end of the finial to help
center the drill bit as in Figure #15.
Then drill a mounting hole for the wire about 3/4” deep as in Figure #16.
Then sand and polish the end of the finial.
Repeat for the other finial.
Figure #15:
Part the nub and dimple the finial end for drilling.
Figure #16:
Drill a mounting hole for the wire. Finish the Ornament Stand
Remove the sphere from the chuck.
Split the temporary joint with a putty knife, mallet, and foam cushion as
in Figure #17. You may need to split
from more than one side because of the joint reinforcing pin in the middle.
Try to carefully align the putty knife on the poster board part of the
temporary joint to avoid denting the edges of the base.
Keep all fingers above the edge of the putty knife.
Peel off the tape and poster board.
Even if you’ve applied finish on the base you should fine the surface
unharmed unless you left the temporary joint assembled for weeks.
Figure #18 shows the completed bases after splitting.
Figure #17:
Split the temporary joint.
Figure #18:
The completed pair of bases. The length of hanger wire you need depends on the size of
ornament you wish to hang. I suggest
starting with 30” of wire. Double
the wire over and clamp in a vise.
Use the 3/8” diameter Ell shaped rod and a drill to twist the wire into a spiral
and form the hanging loop at the same time as in Figure #19.
Twisting the wire forms a more interesting texture than just using a
heavier single wire. It also work
hardens the wire so it will hold its shape better.
The hanging loop looks better if it is adjusted so that the top of the
loop is in line with the twisted wire as in Figure #20.
You can use either needle-nose pliers or looping pliers, shown in Figure
#20, for this. The looping pliers
give perhaps a slightly better result.
An alternate way to create the hanger wire that doesn’t require a 3/8”
ell piece is to double over the wire so that one end is 3” longer than the
other. Clamp the ends in a vise.
Use any size ell wire you have or even the drill’s chuck to twist the
wire into a spiral. Cut off any loop
or untwisted ends of the drill end of the wire.
Trim the shorter wire of the vise end of the wire to where the spiral
stops. Then use looping pliers or a
3/8” rod to form a loop from the longer wire.
I suggest going around the loop twice.
Figure #19:
Twist the mounting wire into a spiral.
Figure #20:
Bend the hanging loop to align with the spiral wire. Cut the untwisted end of the wire off.
Form the mounting wire into an arc either by hand or by bending around a
round object such as your lathe motor.
Insert the hanging wire in the hole drilled in the base to check the arc.
The ornament stand will be most stable if the hanging loop is over the
middle of the base. Once you’re
satisfied with the arc and length of the mounting wire, use CA glue to glue it
into the mounting hole drilled in the finial.
Figure #21 shows the completed pair of ornament stands.
Figure #21:
Completed ornament stands. References
For the Shadow Sphere Jig see:
http://davidreedsmith.com/Articles/ShadowSphereJig/ShadowSphereJig.htm and
http://davidreedsmith.com/Demo/ShadowSphereJigs/ShadowSphereJigs.html For sphere chucks see:
http://davidreedsmith.com/Articles/SlidingEccentricSphereChuck/SlidingEccentricSphereChuck.htm
and the variation in:
http://davidreedsmith.com/Demo/ShadowSphereJigs/Options.pdf
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