For mounting in the 4-jaw lathe chuck a 1 ¾” x 1 1/8”
dowel is turned from leftover oak. It
gets a pilot hole slightly larger than the diameter of the smooth part of the
screw followed by a 3/8” countersunk hole deep enough so the threaded part of
the mounting screw extends beyond the end of the dowel. The drawing below shows what a section of
that looks like. Mounting the blank on
the dowel by running the screw into the previously drilled hole locks the blank
tightly in place so it can then be mounted in the 4-jaw headstock.
To make sure the initial screw installation is in line
with the lathe’s center axis the blank and the screw along with a square screw
driver are put in the lathe per the top photo below. The bottom photo is a closer view of the
blank, screw and square bit driver.
With the initial wood threads cut in the blank the screw
is put in the dowel’s countersunk hole (top photo) and the same process as
above is used to run the screw in until it is holding the dowel tight. In the bottom photo the assembly has been
reversed and clamped in the 4-jaw along with having the tailstock run up tight
to the blank.
Turning the top or heel of the blank to match the first
cut pattern is followed by rough sanding with 120 grit sandpaper which gets rid
of any minor variations and smooths out the piece as shown in the top
photo. Cutting and burning the
decorative grooves at the heel is next.
Shown in the bottom photo both of the grooves are laid out and the right
groove has been cut in using a parting tool.
The top photo has the left groove cut and the right
groove burned in. Burning the groove is
done by holding a thin wire in the groove while the lathe is running. Friction between the wire and the wood heats
the wire enough that the wood in the groove gets charred.
With the grooves completed the waste end of the handle
gets cut off using a fine-toothed Japanese pull saw that leaves a little stub
on the handle’s end identified by the red arrow. Some delicate work with the lathe tools
followed up by fine sanding the whole handle gives the smooth surface shown in
the bottom photo.
The last bit of woodwork before applying the finish is to
drill out the mounting hole that was used by the mounting screw so it matches
the shafts on the files. In the setup
below the drill gets mounted to the lathe’s headstock and a cup shaped adapter
is attached to the live center in the tailstock. This arrangement helps make sure the enlarged
hole is aligned and square with the center axis of the handle. To also help in keeping the hole in line
rather than jumping to the final bit diameter intermediate sized bits are used
to gradually increase the hole’s size.
With those holes sized to fit the file shafts the three
handles are ready for the Danish Oil Finish (DOF).
Three coats of the DOF are applied by wiping on a wet
coat with a cloth then adding more as the finish is absorbed for about 15
minutes. At the end of that time any
excess DOF is removed with a clean cloth and the handle is left to cure
overnight. This photo shows what one
handle looks like when the first coat is applied.
After the DOF has cured for a few days, the files get
epoxied in place. A 24-hour long cure
epoxy is used so I have plenty of time to make adjustments as needed. A little epoxy is used to coat the inside of
the handle using a toothpick. It doesn’t
take much as there is almost no play between the file and the hole in the
handle. I put the epoxy in the hole
because if I coated the file any excess would get scraped off and left in a gob
on the end of the handle which is a mess to clean up. The completed handle and file assemblies are
shown below while the other photo shows how the handle fits in my hand. For reference the total length of the handle
and file assembly is about 6 inches.
The second project in this series is building a case to
hold six small metal files along with the interchangeable handle I had from
another set of files. Right now, the
handle is stored loose in my file drawer while the files are stored in the soft
plastic case they came in. Making a
case for both the files and handle seems like a good idea so I don’t lose the
handle and because it’s only a matter of time before that plastic case begins
to fall apart.
As I normally do the design starts with making several 3D
drawings exploring different configurations to hold the six files along with
the interchangeable handle. Below are
four different versions that didn’t make the cut. Mostly because they made the case was too big
or it didn’t provide easy access to remove the files from the case. The bottom right option has a slot to hold a
brass brush for cleaning the files. In
the end it got deleted since I keep the brushes together so they are easy to
get to and can be used on any file.
Here are the two finalists with the bottom one being the
selected option for a few reasons. I
felt it would give better access to the files and there would be less chance of
them sliding out of the box when it was opened standing upright plus it
addressed some construction issues
In these two renderings the left one has the lid open and
upright but the lid can be opened more so the top lays out flat. This setup will be used when just one or two
files are used on a project then put away.
The right rendering is how the case will be set when it will be out for
a while and several different files are used.
Next Up – Wood Selection & Roughing out Blanks
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