The next set of bowls will be the walnut with the copper
band at the top. Most of the procedure
for turning this group is the same as the previous bowls but there are some
differences. 
First is the way the outside profile of the blank is
initially turned. The top photo shows
the typical turning with its sacrificial base just slightly larger than the
actual bowl’s base. This differs from
the walnut one in the bottom photo whose sacrificial base is the same size as
the top of the bowl. I will go into the
reason why a little later.
Applying a coat of lacquer to the walnut bowls is
next. The reason for putting on a coat
of finish is to seal the walnut before the copper band gets glued in. Because cyanoacrylate or super glue will be
used to glue the copper in place, I am concerned that it might get absorbed
onto the walnut then when the final lacquer finish is applied there might be a
difference between the two materials.
Applying a coat of lacquer now should prevent the super glue from being
absorbed where I don’t want it to be. The
top photo shows the setup with the air brush on the left, the bowl to be
finished and the lazy Susan on the right which makes applying the lacquer to
the bowl easier. The bottom photo shows
the bowl on the lazy-susan ready for finishing. 
After the lacquer cures overnight, a slot is cut into the
bowl for the 12-gauge copper wire. By
coincidence my narrow parting tool is .078” thick and the wire is .08”. This gives me a .002” interference fit which
with the super glue should hold it in place.
The slot is cut to about .05” deep leaving the wire proud of the surface
when installed.
Installation of the wire starts by squaring one end then
applying some glue in the slot about a 1½” back of where the wire’s end will
be. The wire is then hammered down in
place and that area sprayed with accelerator which almost instantaneously cures
the glue locking the wire in the slot.
The process of hammering the wire in place and gluing is repeated until
I get to within about 1½” of the start.
The top photo shows most of the wire glued in place with just the final
fitting to do. The final fitting is done
with a small file until the ends fit tight and square when pressed into the
slot. The bottom photo is what the ends
look like fitted and ready to be glued in place. Earlier I talked about leaving the base the
same size as the top of the bowl. This
is where that comes into play. With the base the same size as the top of the bowl the whole piece is stabilized acting like
a cylinder which makes the wire installation a lot easier. Without a full size base it I would be trying
to install the wire on a cone which would be a lot less stable.
The last bit of the wire ends get clamped to hold them in
place for gluing in. When that’s done
glue is applied all along the joint between the copper and the walnut. Because the glue is very thin capillary
action pulls it into any voids between the two materials. The top left photo shows that done with the
bowl mounted in the lathe. Next with the
lathe on a slow speed a metal file is used to cut away the copper that is above
the bowls surface. The top right photo
shows where about half of the copper has been removed. This continues until the copper is flush with
the bowl shown in the bottom left photo.
Sanding the bowl and polishing the copper is next using finer and finer grits
ending up with 800 grit paper. That’s
been completed in the lower right photo that also has a red circle around the joint where the ends come together.
Here is what the small bowl looks like ready to have the
base resized and hollowed out. You can
also see the pencil lines where it will be cut for the top and bottom.
Once hollowed out and the top rounded the bowl can be
parted off like the others. Here are all
three of the walnut bowls ready to have their sacrificial bases cut off.
With three of the four sets ready to finish I decided to
start applying the required four coats of lacquer to both the inside and
out. If the bowls were set on a flat
surface and sprayed, they probably would get stuck to that surface. Also, I have found that if there is space for
free air flow around the piece being sprayed I get a better finish. To get that simple cardboard stands are built
to set the bowls on for spraying. They
are set on a lazy-susan which makes them easy to spray. The top photo shows the one for the small
bowl. For stability cutoffs from when
the initial square blocks were cut round get stapled to the cardboard. The bottom photo shows the maple and cherry
bowls with one coat of finish on the outside.
The setup for spraying the inside of the bowls is similar
to the outside in that they are elevated up off the lazy-susan for
spraying. After the first coat the bowls
are wet sanded with a 1,500 grit sanding pad to remove any dust and
irregularities in the surface. A photo
does not show the difference after sanding but you sure can feel it. Going forward my plan is to spray lacquer in
the morning when it’s calm then do some wood turning in the afternoon after the
lacquer has dried dust free ending the day with some cleanup so the spraying
can continue the next morning.
Next Up – Adding the Turquoise Band to the Oak Bowls
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