From this point on the process for making the remaining
handles is the same as the first one although it does go a little faster at
about 2 hours each. It seems the closer
I get to the Pattern #1 match the slower is goes as I want it as close to a
perfect match as I can get. Here are the
four matching handles and have to say being very careful and frequently
checking my progress paid off. After all
there is no “Undo” button if the cuts are too deep.
Cutting the 7/16” threaded rod that will be epoxied into
the handles is next. I cut them to
length using a jig saw with a metal cutting blade. A hack saw could have been used but the jig
saw is easier. Here the rod is clamped
into the vice ready to be cut. One other
thing, if you look at the right side of the vice you can see a scrap piece of
wood with a clamp on the end. That acts
as a spacer to keep the vice jaws parallel when it is tightened. The clamp on the spacer keeps it from falling
to the floor when the vice is loosened.
However, after cutting the rod its threads and the cut
ends are messed up and need a little help before they are usable.
The cleanup is done on a grinder. The nuts on the rod give me a place to hold
on to it and set the grind angle. Once
the grinder is running the rod is turned while being kept at the same
angle. Once ground the rod is ready to
be used.
Epoxying the rods into the handles is next. A 5-minute 2-part epoxy is used. Here are the completed handles clamped up for
curing. Clamps are used to hold the rod
in place while the epoxy cures. The
clamps keep the rods fully inserted in the handles as I have had rods want to
creep out before the epoxy sets. I think
it’s due to the epoxy sealing around the rod causing air to be compressed as
the rod is pressed into place.
Once the epoxy is cured the handles are removed from the
clamps and screwed into the inserts in the body.
The last item before applying a finish is to make the
blade locking screws. I had ordered
steel knurled knobs but when I changed the size of the body they were too
short. While working on the square tube
I got to thinking that I wanted a material softer than the tool steel of the
router blade to apply the locking pressure and brass fits the bill. That’s why the insert is also brass so as to
not have dissimilar materials which could introduce galvanic corrosion. The knobs start by cutting a ¾” cube from the
Texas Ebony base cutoffs. Here is the
last cut being made on the bandsaw.
Since there is no way I am going to get my fingers that close to the
bandsaw blade I use a screw clamp to hold the piece while being cut.
Using a centering square, the center of the end is
located, center punched and it’s ready for the drill press. The hole will be used for mounting the piece
on the lathe.
Before mounting on the lathe, the disk sander is used to
round off the corners to help make the turning easier. That’s done since the attachment is a little
delicate and the less stress the better.
The blank is attached to an oak mandrel via a screw that
gets run into the hole drilled in the blank’s center. The oak piece is then clamped in the 4-jaw
chuck and the turning can begin. Here is
the blank after it has been turned round and you can see how it all fits
together.
In order to provide a better grip to the knob 12 recesses
will be cut around the knob’s perimeter.
That starts with marking the blank into 12 equally spaced sections. The lathe has an indexing feature that locks
every 30 degrees giving the 12 sections.
The photo below shows the threaded rod near the left side of the photo
run into the detent in the lathe shaft and the section marks on the knob at the lower right.
The recesses are made using the oscillating drum sander
by very carefully aligning the white mark on the knob with the centerline of
the sander then gently pressing it against the drum. The piece of plywood that the sander drum is
coming up through has a hole the size of the drum and is clamped to the
sander’s cast iron top. It’s so I have
full support for the knob when sanding.
In the right photo you can see the end result of the process with the
recesses made but in dire need of some additional sanding to make them
smooth.
However, before that I need to go back to the lathe and
drill a hole in the base of the knob where the threaded rod will go. This is the setup at the lathe ready to
go. There are a couple of things that
need to be explained though. First, is
why the final sanding of the recesses are not yet done. That’s because if when the knob is clamped in
the 4-jaw chuck the recesses get dented I haven’t gone through all the work
finish sanding them only to have to do it again. Second, is the narrow strip of wood held in
place with masking tape backing up the knob.
That’s so I don’t have to tighten the chuck down so much which reduces
the chance of denting the knob. Without
it the chuck has to be tightened down enough to keep the knob from getting
pushed into the chuck’s jaws when drilling the hole.
Once the hole is drilled, I can start hand sanding which
starts with a finer grit tube from the drum sander. Finer grits of sandpaper are used ending up
with 320 grit paper until all the scratch marks are gone. The knob on the far left is a prototype and
here is used to give me a better grip during sanding.
With the knob completed here are a couple of views of the
project completed except for finishing.
Next Up – Finishing & a Stopped Dado
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