Once all the parts are screwed together the piece is
bolted onto the sliding base. The top
photo shows the back with its bracing and five of the six bolts holding it to
the sliding base. The bottom photo shows
the face of the fence where the top will be clamped on. Checking the fence for squareness against the
table saw top gave good news as it is so close to being dead on that no adjustments
are needed. The vertical piece is an old
plastic laminate counter top and as you can see the plastic laminate is facing
in. That’s because I wanted a surface
with some tooth so when the top is clamped in place it would not slip.
Next is to clamp the top in place to see how the whole
assembly is going to work. Here is how
it looks when ready to make a horizontal cut.
No problem here, the top is held securely in place with four clamps and
is very stable.
The vertical clamp did give me a little problem as only
three clamps can be used and I really want to use four – one at each
corner. If you look at the lower left
you can see I ended up making the fourth clamp to hold that corner tight
against the tall fence. The clamp is
made from a short length of 3/8” rod, 2 nuts and washers plus a spacer matching
the thickness of the top all mounted through a hole drilled in the tall fence.
The photo below shows my first test cut with the blade
set at 29 degrees taking only a partial cut.
The final pass will make the bevel much wider. Everything worked well in making the cut, the
sled ran smooth while the tall fence held the top solidly in place. You can also see a closer view of the fourth
clamp described above.
Next is to remove the top, rotate it 90 degrees then
clamp in place. In this photo you can
see the second test cut down the long edge of the top. This cut came out better than the first. I would like to say it’s because I learned
from the first one but in reality, it’s mostly because the first cut was across
the grain and this one is with the grain.
A closer look at the corner where the two cuts come
together gives a preview of what the finished geometry will look like. On the vertical end the pencil line shows how
much more I have to take off. At this
point I am happy with the results and can proceed with making the finish
beveled cuts.
Because I did not know for sure if any problems were
going to show up in the test bevel cuts the top blanks were left long just in
case, I needed to start over in making the cuts. With the successful tests the blanks can now
be cut to their final length using the panel jig. As the back of the top is a square cut the
final width will be cut after the bevels.
Just in case something goes wrong.
Final bevel is cut in two passes, first one takes off
almost all of the material but can leave some burn marks as in the top
photo. The bottom photo shows how making a second pass taking off less than the saw blade’s width gives a much cleaner
surface.
That does not mean the bevel cuts are of a finished
quality. I still need to sand them
starting with 60 grit and finishing up with 220 on the long edge. The crosscut ends are taken to 400 grit. That’s because at the same smoothness end
grain takes up more stain resulting in a darker finish. Going a step or two finer results in a
surface that absorbs less stain making the end grain blend in better with the
long grain.
Because I want to keep the edges of the bevels crisp and
the bevel itself flat a pad sander is not such a good choice as the pad can
flex rounding things out a bit. In cases
like this a piece of MDF or smooth plywood is used faced with hook material
which the loop backed sand paper is mounted to it. That way I end up with the paper being backed
by a hard material with very little give.
Here is what I mean: on the left is the 220-grit loop backed sandpaper,
the disk it goes on is next with the hook backing and the next two disks have
the sandpaper applied.
With all the bevels cut and sanded I can rip the tops to
their final width. This photo shows one
set in place on top of the cabinet.
Mounting the top to the sub-base is next. The attachment is not as simple as either
gluing the top down or running some screws up from inside the cabinet through
the sub-base into the top. That’s
because the sub base is ¾” plywood and the top is solid 1¼” oak. When exposed to different humidity levels the
plywood is stable but the solid oak will expand or contract across the grain in
response to the humidity change. If the
top is solidly attached to the plywood the forces can be enough for it to crack
and that’s not a good plan. To get
around this the top is screwed to the plywood with 8 screws around the
perimeter. The two at the center of the
ends are run up through a small hole in the plywood to hold the top in
place. To allow for the top to expand
and contract about its center line the holes down the long edges are really
slots with the screws just pulled down snug.
This leaves the top free to expand or contract and not crack as the
humidity changes.
The slots require the most work. Once laid out the center point is marked with
a punch then a hole is drilled at each end and one between them. Here you can see the alignment hole in the center, punch marks for the slot at
the lower right of the photo, and the three slot holes
drilled at the upper left.
After the holes are drilled the interior edges are
roughed out using a Dremel tool with a burr then cleaned up with a flat and
round riffler. This is what the slots
and the center hole look like completed.
Next up – The Handles
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