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Bill Smith chats with our members.
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Bill started with some discussion of his current work.
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Here is an example of a glued up piece before it has been turned.
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DEMONSTRATION BILL SMITH 4/11/02
Bill Smith demonstrated how he turns open segmented forms.
The piece he demonstrated was made of 12 pieces per layer, each piece arranged with a gap between it
and the next and the gaps covered by the pieces of the next layer. The design was laid out on graph
paper. The spaces on the graph paper match the thickness of the material used, 3/8" in this case. Bill
measures the diameter of each layer of the design. The diameter is measured at the widest point and
rounded up to the closest 1/4 inch. Bill has prepared a chart to indicate the length of each piece for
various diameters which will result in a gap to solid ratio of 1 to 3. The length of the front of each
piece is critical.
Bill uses straight grained, sound wood that glues well. Quartersawn is preferred
as dimensional stability is essential. Bill sets the miter gauge of the saw at 10 degrees for a 12 segment
piece and uses a good quality crosscut blade. A stop block is set to the outside length, the length
found on the chart. The stock is flipped for each cut so the result is a trapezoid. The 12 pieces for
each layer and any spares are cut.
Bill attaches an index wheel to the spindle, outboard if
possible. The index wheel has lines to indicate the position of each piece. For a 12 segment form the
lines are spaced at 15 degree intervals around the wheel. Bill fastens a jig to the ways of the lathe.
The jig is made of a piece of angle bar, the top and end of which are centered precisely on the spindle.
The jig has a stop block set to the radius of the layer.
Bill begins the assembly with a solid
bottom held by a glue block in a chuck. The 12 segments of the first open layer are glued to the bottom
with Titebond glue. The position of each piece is located by the jig and the index wheel. Bill applies
glue with a small pallet knife. Glue is applied to the edges of each piece. The spindle is rotated
to the next index line and another piece is placed on the jig and glued. After all the pieces in a layer
have been glued to the bottom the layer is faced off with a scraper. The glue sets up quickly. Bill
usually cuts the pieces for the next layer while the glue sets up.
After all the open segmented
layers have been glued up a closed segment or solid layer is glued to make the top layer. Bill uses
a gouge to knock off the edges of the glued pieces then uses a scraper to turn the final outside shape.
As Bill nears the final shape he makes a parting cut at top and bottom to define the shape. He uses
a gouge on the solid top and bottom and a scraper on the open part. Bill begins shaping the inside with
a gouge as far as it will go then finishes with a hollowing tool such as an Ellsworth, Stewart or similar
tool. A 1" wall thickness gives a lot of design options.
Bill power sands and uses hand held
strips held at end of strips for final sanding with finer grits. He finishes with spray Deft and parts
off.
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Bill used helpful charts to show the angles required for the shape he is shooting for.
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