Deciding how wide to make the 6/4 rough-cut leg blanks is
a bit of a balancing act. Wider gives me
more material to work with but increases the cup that has to be removed. Also, after removing the curve from the
planks a few problems reared their ugly heads.
Everything from some cracks and splits that were not visible to some
knots that showed up when I had a clean edge.
After a lot of measuring and marking out different widths 4” more or
less looks like it will give me enough to get the finished pieces while getting
rid of most of the problems.
Here the cutting jig is clamped in place to give a
roughly 4” finished width piece. The
plank is not wide enough to clamp the jig in place without the clamps
interfering with the cut so I have to put on multiple clamps and relocate them
as the cut is made. The top photo shows
the initial setup and the bottom one shows the completed cut.
Converting the rough-sawn faces to nice smooth ones is
accomplished by the use of a surfacer.
Its knives spin at about 9,000 RPM’s and smooth the surface out by
taking off 1/32” per pass. I could take
more but I don’t want to stress the machine.
Also, shaving off a little at a time gradually reveals what the wood
looks like and gives me a chance to decide which face needs the most removed to
obtain the best-looking result. Here it
shows what a board looks like pretty much done.
By the time I am finished the red shop vacuum will probably need to be emptied.
With nice flat, smooth faces on the boards I could turn
my attention to the edges. Using the
ripping jig and my circular saw gave a more or less straight edge. However, because the boards were cupped and
when clamped in place the jig followed the curve the edges are not 90 degrees
to the faces. Before I could rip a good
straight and square edge on the table saw I needed to true up the initial cut
edge. The method for that is to use my
8’ long level to find the high and low spots.
That’s done by using a piece of paper to find the gaps between the level
and the board then marking the high areas.
Using either a hand or power plane to knock off the high spots allows me
to true up the edge to within about the thickness of the piece of paper.
Ripping a good edge on the table saw is next. I start by clamping the long level to the
table saw’s fence. A long fence will
help average out any high or low points giving a straighter edge. First is to put the edge that was just
cleaned up with the planes against the long level then taking a light cut to
get my first true square edge. Second is
to flip the board putting the just cut edge against the level then taking
another light cut. If everything works
out right, I now have a board with all four faces straight, square and
true. Now it’s time to wait to see if
the boards are stable and stay straight or if with all they have been through
some internal stresses have been released.
That can cause any one or all of the following problems to show up;
twisting, cupping, bending, getting waves or in general not staying straight
and true.
For most of the pieces I was able to work around the
flaws to get a clear part. There were a
couple that will probably need some help as the project progresses. Then there was one that no matter how I laid it out it was being a real problem child.
The photo below shows what I mean.
Each of the chalk circles outline some sort of problem; cracks, splits,
worm holes, knots or a bark inclusion.
Most of them will be gone or hidden but one knot and the bark inclusion
will need to be addressed later. The
horizontal pencil line is roughly the taper to be cut which is next.
Cutting the taper on the legs is normally done using my tapering jig
which clamps the work securely in place and has a variety of clamping options
that allows most any long taper to be cut easily. This is what that jig looks like ready to cut
a taper.
Unfortunately, its maximum part length is about 44” which
is way to short for the 78 ½” length of these legs. If it was just one piece, I probably would
cut it with either the bandsaw or use the ripping jig and circular saw
combination then clean it up with a router run against a straight edge. However, I need to make 8 identical legs so
that’s not a good idea for either efficiency or consistency. Because there are that many pieces to cut it
makes sense for me to invest a little time in a jig to cut them all the
same. Below is my plan for the jig. It’s pretty simple and should hold the leg in
place to make repeatable cutting. The
light tan is the jig, the brown is the finished leg and the white is what gets
cut off the leg blank. The taper will be
cut first then cut to length on the chop saw.
Next up – Making & Using the Taper Jig
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