Once I had a pair of angled pieces sized to what’s needed
the next step is to glue the two of them together. In order to make sure the alignment is the
same for all the glued-up blanks the jig below is used. A plywood base gets covered with a piece of
6 mil polyethylene so the blank won’t get glued to the base. A reference rail at the far side gets screwed
in place. Two end pieces are cut to the
exact finished width of the blank and the front rail is held in place with the
clamps shown. These last three pieces are
not fastened down in case the width needs to be adjusted. Last is a caul that is used to apply even
pressure to the glue-up. The face of the
caul towards the camera is covered with packing tape so it won’t get glued to
the blank.
The glue-up has three steps: First, one piece gets glue applied to the
angled face as shown in the top photo.
Second, the other angled piece gets set in place per the bottom photo.
Last is to clamp the caul in place. It’s here where the long reference rails come
into play. Because of the glue on the
angled pieces when the clamps are tightened, the pieces want to slide apart but
the rails keep that from happening. This
short glue-up is a proof-of-concept to see if everything works. In production the blanks will run nearly the full length of the jig.
After letting the blank cure overnight, it is removed
from the jig and the face joints with the tapered edges are checked to see if
they came out flush which they did. A
couple quick passes through the thickness sander removed what little glue had
come to the surface and bring the blank to its final thickness. The photo below is the finished test blank
where I have darkened one of the angled pieces to represent the contrasting
wood. Also, one of the finished segments
is drawn on it. In use the blanks get
cut into 1.418” wide pieces then each end is angled at 15 degrees. One thing that came up in the glue assembly
is the long edge of the angled piece gets sanded to a sharp edge and that edge
is very fragile. In fact in a couple of places the edge flaked off. It ended up not being a problem here because
the blank had to be taken down a few hundredths of an inch to get it to final
thickness. However, to forestall that
problem I am going to make another test piece and not taper the edge to nothing
but leave a tiny edge to act as a reinforcement. It should not be a problem but the next test
will let me know.
In the top photo the next test piece’s thinner
edge (red arrow). It’s only about 1/32” wide and for
reference the full thickness of the piece is right at 5/8”. After checking to see how the pieces fit in
the gluing jig, I decided to thin the edge down to about 1/64” and did the
glue-up using that lip. The bottom photo
is what the glued up blank looks like when pulled out of the jig before I start
working on it.
The two photos below show the blank before and after
running it through the thickness sander.
A good point of reference is the small knot about a quarter of the way
in from the right edge. As you can see
the joint has all but disappeared.
Before I started to flatten the piece, I was a little worried that the
slight raised edge might cause a rocking problem when sanding throwing the
blank out of square. Fortunately, that
did not happen. Taking what was learned
from the two tests right now the plan is to slightly thicken the original
angled pieces and thin down the edge even more making it as thin as possible
without losing the crisp edge. If it
does get damaged during the glue-up since the assembled piece is slightly
oversized that will give me some wiggle room when flattening and bringing the blank
to final thickness.
Once the feature blanks are sanded to final thickness it
gets cut into blocks for the segments.
In the photo a couple of the blocks are laid out showing the individual
segments. The dashed line represents the
transition from one angled piece to the other.
One other note is that so far, I have only used scrap plywood and scrap
2x4 material for the jig testing. The
actual blanks will have the grain running across them rather than vertically as
show in this piece. That’s because the
bottom of the segment will end up being the exposed face of the bowl which
needs to be long grain and if this piece with the grain top to bottom was used
the exposed face would be end grain rather than the long grain.
Selecting the material for the feature ring shown in the
top drawing is next. I need light and
dark woods to provide contrast within the ring so decided to use hard maple and
dark cherry. The bottom photo shows the
pieces selected and the preliminary marking of how they will be cut up. One problem is with the width of the cherry
since it and the maple pieces need to be the same width when the angled pieces
are glued-up. Since the cherry is
narrower than the maple two pieces of cherry will be glued up to equal the
maple’s width while at the same time making sure that joint lines up with where
the segments will get cut apart. 
I had a concern with the amount of waste when ripping the
blanks to their final width then cutting the angle on the bandsaw. In the drawings below the blue indicates the
waste. The top drawing is of a single
angled piece cut from a final width blank.
My solution is the bottom drawing which shows how overlapping the angled
pieces on a wider blank makes less waste.
The dotted line between the two angled pieces in the bottom drawing is
my bandsaw cut line.
Next Up – Starting on Making Feature Ring Blanks
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