Earlier on when making the divider blanks rather than
bringing them down to their final thickness they were left about 1/64”
oversize. Since their final curved shape
and length is done as well as the slotted end and center caps they can be
brought to their final thickness. That’s
done using the thickness sander which allows me to very precisely sand off just
a few thousands of an inch per pass to get that perfect fit. Only change was to replace the 120 grit
sandpaper with 220 grit paper so I would get a finish sanded surface.
Once the dividers are fitted to the slots, I could do a
test fit of all the pieces completed so far as in the top drawing. What’s missing in the other end cap (red
arrow). For whatever reason I didn’t cut
that part when I did the other two and need make it now. It’s not a big problem since the blank the
others were cut from is still available.
Fortunately, the router is still set for the small radius made on the
center slotted piece so that’s easy.
What will take some time is to go through the process of cutting it to
exact length and resetting the router to match the two end slot cuts. 
There is no reason to go through the setup and machining
processes for making the end cap since they have already been covered so here
is the end result dry fitted and clamped together.
Gluing the dividers in place comes next but before that’s
done the end grain of the three slotted pieces needs to be sanded because once
the dividers are glued in place I won’t be able to sand them. They are hand sanded starting with 220 grit,
moving to 320 and finishing with 400 which in the photo is in the vice. If you look at the bottom slotted piece you
can see numbers 1-7 written next to the slots.
That’s so I can match up the dividers to the slots. Even though all the slots were cut with the
same router bit and the dividers were sanded at the same thickness setting in
the sander there is still a very tiny bit of variation so some dividers fit
better in some slots than others.
The glue-up is done in three steps to give me plenty of
time to get the everything together without rushing. The first step is to glue the center dividers
into just the right end block (red arrow).
To keep the pieces from getting glued to the workbench a small piece of
plastic film is laid down first. The
little spacer at the left end (red ellipse) up against the square takes the
place of the outside divider which gets glued on in the third step. The second step is to glue the dividers into
the slotted center piece. Once the glue
is spread in the slot the clamping looks the same as what’s shown.
The third and last step is to glue the two outside
dividers to the end caps (red arrows).
The end caps are a little different in that they don’t have a slot for
these two dividers but fit in a rabbit.
A closeup view of the joint is shown in the upper right inset.
Once the glue cures, I need to flatten the bottom and the
top of the assembly because no matter how careful pieces are measured, cut and
assembled there will always be a little variance. Here is what the top of the assembly looks
like after all the edges have been marked with pencil lines and is ready for
flattening. 
The flattening setup is a piece of 150 grit sandpaper
clamped down to a known flat surface.
Here that’s the extension to my table saw. Process is to place the assembly on the sandpaper
and carefully make passes lifting after each pass and rotating end for end
after every five or so passes. Rotating
helps to keep the sanding even in case I am putting uneven pressure on one of
the ends. Sanding passes are repeated
until all the pencil marks are gone and all the individual pieces are in the
same plane. Here the bottom of the
assembly is shown completed.
The same process is done for the top surface except once
flattened the 150-grit sandpaper gets changed to 220-grit for a smoother
surface since it’s exposed. Once that’s
done some hand sanding of the sharp exposed edges to soften them is done using
220-grit paper. Also, the transitions
from the curved parts of the dividers to their flat tops along with the rounded
edges in the handle pocket all get touched up.
These results are shown in the top photo. The bottom photo is a close in view of how
the dividers seamlessly fit into their slots when all is completed.
Gluing the bottom
on comes next. The bottom blank has been
setting aside while I have been working on other parts. When checked it’s both are flat and true so
the only thing required is to run it through the thickness sander loaded with
220 grit sandpaper giving it a near finish sanded surface. Rather than cut the bottom to exactly fit the
glued-up divider assembly the bottom gets cut about 3/16” oversize. This gives me some flexibility when gluing it
on. If it were cut to the exact size and
the glue-up didn’t go perfectly then I would have a real problem to fix. Anyway, here is what it looks like all
clamped up.
This is what things look like after the glue cures and
the clamps are removed. The bottom photo
is a close view and it’s easy to see the bottom’s lip that needs to be
removed. Before doing the final trim, I
will cut the overhang down to about the pencil line so there is less material
to be removed with the router.
Cutting the bottom flush with the sides is done with a
trim bit in the router. Here the bit has
a bearing that runs along the guide surface and the carbide cutting edge cuts
the bottom flush with the divider assembly.
The red arrow points to where I stopped trimming the edge to take the
photo. Once the edges are cut a little
sanding and the bottom fits perfectly.
Next Up – Fitting Riser & Stop Blocks – Cutting End
Cap & Gluing On
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