Having let the parts set I checked them and they were all
flat. The blanks for the top and bottom
of the case are a ¼” thick and need to be 9” wide by 10 ¼” long.
I do not have a 9” wide walnut board and if I did when I
cut it to ¼” thick it almost certainly would warp. To get a blank the will remain flat I will
glue up three individual pieces. Like
before I spent some time playing around with the pieces to get the best match
of grain and color. Once done I numbered
them so they will go together in the right order. Here is one set ready to be glued up. If you take a close look you can see an “UP”
and a “DN” one either side of the joint.
Those indicate which way they get run through the table saw. That is so if there is any variance in the
saw blade cutting a perfect 90 degree it would be cancelled out.
I can now start gluing up the panels. To do so a couple of bar clamps are set
vertically, glue is applied to one edge and they are clamped up. I take particular care to align the boards up
with the bars. That is so when I apply
pressure it is centered on the pieces and there is less of a chance that I will
end up with them bowed. The center clamp
helps keep the two pieces flush. I did
not have a problem with the ends but the center needed a little “help” to stay
aligned. They are let set overnight to
cure then I go through the same process to add the third piece as shown in the
photo below.
Once cured I trimmed up the edges then ran it through the thickness sander to flush up the little variances in the joints ending up with
blanks for the top and bottom. I will
let these sit for a bit to make sure they stay flat.
Next up is the dividers, right now the they are just a
couple of hundredths of an inch over ¼” thick.
Once I have finished shaping them I will use the thickness sander to
take them right to ¼”.
I started by ripping the pieces to finished length and
width. With that done I taped them
together so I could cut the center arc in all the pieces at once. A paper template is applied and they are
ready to go.
They are cut out on the bandsaw. I cut half way in from one end then turn the
piece around and cut from the other. In
the top photo I have cut half way and am ready to cut from the other
direction. The block on the right side
is to help keep the blanks square with the table. The bottom photo shows the resulting cutout.
To smooth the cut edge, I use an oscillating drum
sander. As the drum spins it also goes
up and down giving a better finished surface.
There are various size drums and grits of sandpaper. A coarse grit cleans up the rough face and a
finer grit completes the process. Well
almost, the finest sleeve I have is 120 grit and that’s not good enough. Later on, I will do some hand sanding for my
final surface. The top photo is before I
start and the bottom shows the completed face.
The next parts are the ends. I take the glued-up blank from Post #3 run it
through the thickness sander until it matches the 1¼” height of the dividers
and cut off two parts that will make the ends.
The grain direction is a little different than usual and you see that in
the bottom photo. The white lines are
the center of the slots for the dividers.
Cutting the slots is done with a ¼” stack dado. First, I set the ¼” cut depth using a depth
gauge my dad made for me years ago. A
test cut and a little adjustment gave me my dead on ¼” depth.
The process for making the cuts is to work from the
center out. Here you can see where the
center cut is done along with one on either side. I only measure one side then flip the board
end for end to make a perfect mirror copy.
That process is repeated for the next two then for the last cut a
sacrificial piece is clamped to the fence then it is run up until it just touches
the blade and the cut is made.
Now I can take the dividers that are just a little too
thick and run them through the thickness sander to get them just right. Well really, I am taking them down to about 5
thousandths thicker that what I want to end up with. The last little bit will be removed with 320
grit sandpaper. If I were to fit them
just right then sand they would be too loose.
The slot measures .250 inches, right at ¼” which is what I took the
dividers down to. However, for the
dividers to have just a little friction fit I needed take them down to .245
inches thick. Below is the test fit with
the rifflers dropped in place.
Before gluing the dividers in place, I finish sanded the
end grain of the end pieces. I had to do
that before gluing them in since once glued in place sanding will be next to
impossible. Also, since it is end grain
I need to go to a finer grit, 400 in this case, than I would have to if it were
face grain. To keep an absolute flat
face when sanding I clamp a piece of sandpaper to a granite tile.
Below the bottom piece shows the cut right off the saw
and the top one is the finish sanded end.
Next Up – Base Assembly & Top Part 1
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