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{ Wednesday, 10 September 2008 }
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Leonard Cleveland turns bird house ornaments
Compiled by Dale Dallon
Leonard demonstrated the turning of two different bird houses. Both had
square-edge roof sections with and upper spindle or finial. One had a
cylindrical body section and the other had an elongated, hour-glass shaped body.
Both bodies had spindle or finial ornamentation at the bottom. The roof section
and the body section are turned as separate pieces from contrasting woods and
then joined using C/A glue. Sizes and shapes can be quite variable to suit the
turner's taste and stock availability. The techniques for both houses were
similar so only one process is recorded in these notes.
(Click here
to see pictures of Leonard's demonstration.)
Leonard began by showing us some tools he finds very useful in this type of
turning. These included:
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- A Forstner bit jig—a block of wood in which sample borings were
made from several sizes of Forstner bits to help in selecting the proper bit
size and to assist in fitting tenons.
- Inside/outside caliper.
- A flexible-neck fiber optic flashlight.
- A rubber syringe and a compressed CO2 capsule blaster to blow dust out
of borings.
- Anti-lock gasket for the head stock spindle.
- A golf ball to act as a compression buffer between an egg-cup center
and the wood.
- As a tool carrier, Leonard has used a 5 gallon plastic bucket partially
filled with sawdust. He cut circular holes in the lid which serves as a tool
holder/spacer. The tools are placed through the holes cutting-edge downward
into the saw dust. The end of the tool handles have been marked so they can
be identified before removing them from the bucket.
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Turning the roof section
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| 1. A square blank is mounted in a 4-jaw chuck using a cup center
in the tailstock for stability.
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| 2. Square off the face of the blank using a gouge. This face will
be the bottom of the roof section.
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| 3. Bore a ½ inch deep recess in the face with a Forstner
bit. The bit size will depend on the diameter of the piece being turned. In the
first case, Leonard used a 1¼ inch bit and in the second he used a
¾ inch bit. This boring should be done at reduced speed.
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| 4. Dish the face to a concave shape with a gouge. It is important
to stay away from the square corners of the blank to avoid damaging them. The
first dishing cuts should be started at the edge of the boring cutting from
outside to inside then started successive cuts gradually out toward the edge.
On light colored stock, Leonard likes to mark the corners with a pencil line so
he can visualize the edge. The ghost image of the corners is often difficult to
see with the piece turning. The heel of the gouge can also be used to locate
the corners before starting the final cuts. This dished area is the bottom
surface of the roof section. When the dishing is completed there should still
be enough depth (1/8 – 1/4 inch?) of bored recess remaining to receive the
tenon of the body section to be joined later.
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| 5. Begin shaping the upper surface of the roof with a gouge. The
starting cuts should be made will above the square corners to avoid damaging
them. Leonard recommends marking a line on the blank ¼ inch above the
corner to provide a visual reminder of the danger zone.
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| 6. Gradually reduce the upper part of the blank (that nearest the
chuck) to a cylinder using cove cuts away from the corners. This area becomes
the decorative upper spindle or finial of the roof section.
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| 7. Using the cup center in the tail stock to help maintain the
centerline, Leonard moved his blank out of the chuck to expose more wood and
reduce the length of the chucking foot. With the cup center still in place for
stability, finish shaping the spindle/finial to the desired contour.
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| 8. Sand the entire roof section. The sharp edges and corners of
the roof should be eased slightly with sand paper. Leonard never sands beyond a
240 grit. He feels that surface provides just enough tooth to help hold the
spray-on finishes he uses.
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| 9. Remove the roof section from the chuck leaving the square
chucking foot in place for future use.
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Turning the body section
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| 1. Mount another square blank in the 4-jaw chuck.
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| 2. Square off the face of the blank with a gouge. This face will be
the top of the body section.
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| 3. With a gouge, round down the blank to a cylinder.
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| 4. Cut a ¼ inch long tenon in the end of the cylinder to
make a reasonably snug fit in the tenon recess of the roof section. The
inside/outside caliper can be useful to get close then do trial and error
cutting to achieve the desired fit. When the desired fit is achieved, undercut
the shoulder of the tenon slightly to capture any excess glue when the sections
are joined.
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| 5. Drill holes in the side of the roughed cylinder, one to be the
bird entrance and the other to receive the perch. Leonard used a ¼ inch
bit for the entrance hole and a 3/16 inch bit for the perch hole. Both holes
can be drilled on the same axial line, or the perch can be offset a little from
the entrance for a different visual effect. The placement of these holes is a
design question. In the elongated hour glass example, Leonard placed the holes
near the center of the body length where the waist of the hour glass shape
would occur. These holes are drilled before the body is bored so they will have
clean edges at the boring. If drilled after the interior is bored you will
usually get feathering of the fibers where the drill bit pierces the hollow
chamber.
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| 6. Bore the interior chamber with a Forstner bit. The depth of this
boring is dependent on the design of the body. It must not go through the
bottom but it must go past the drilled holes. You would probably like to have
it as deep as the body design will allow to reduce weight. In this example,
Leonard used a ¾ inch Forstner and bored 1¾ inches deep.
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| 7. Using a large cone center in the tail stock for stability,
finalize the shape of the body and rough shape the lower spindle/finial that
will be the bottom of the ornament. Leave enough wood in the spindle to provide
stability.
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| 8. Sand the body section to 240 grit.
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| 9. Apply C/A glue to the wall of the recess in the bottom of the
roof section and join the roof section to the body section. Use the cone center
to hold the roof section in position as the glue sets.
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| 10. With the cone center still stabilizing the piece, turn off the
square chucking foot from the roof section, remove all excess wood from the
upper spindle/finial and refine the roof and spindle shape. Sand roof section
and spindle to 240 grit. Remove the tail center stub from the finial and
manually sand the cut-off area.
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| 11. Using the cone center as a center-line reference, pull the
piece outward from the chuck to expose more wood and minimize the chucking
foot.
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| 12. Finish shaping the bottom spindle/finial. Sand the bottom
spindle to 240 grit. Carefully part off the piece from the chuck and manually
sand the cut-off area.
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Turning the perch
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| 1. Using a pin chuck, mount a small square blank. Leonard used
about 3/8 × 3/8 × 6.
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| 2. Turn a tenon in the end of the perch to fit the 3/16 inch hole
previously drilled in the body section.
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| 3. Shape the perch as desired, sand and part off.
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| 4. Glue the perch tenon into the 3/16 inch hole.
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Alternatives
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- Rather than turning a perch you can use small twigs with interesting
natural shapes.
- It might be advantageous to turn the body section first where it is the
limiting dimension, then fit the roof section to the body tenon rather than
the reverse sequence as described above.
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(Click here
to see pictures of Leonard's demonstration.)