What you ask is a Riffler? Well, in this case it’s not a really good guitar player but small, quick
cutting rasps used by woodworkers, sculptors and miniature builders for adding
fine detail and intricate shaping to their work. My son recently got me a nice set of straight
160mm (6 1/4”) Italian cut rifflers and an interchangeable wood handle.
In thinking about how I will use them and some
experimentation I came to some conclusions.
- The handle needed to be a bit bigger for me to comfortably use.
- Since I would be switching back and forth between the shapes having to change the handle all the time would be a pain.
- I would like to have a nice case to keep them all together and protected.
There are a lot of options for a case that range from a
simple canvas roll to a hard case of some type.
Since I am a woodworker I gravitated toward some type of wood case. However, before I could design the case I
needed to settle on the size and shape of the handles. In the past I have made some handles for my
other files and rasps that just fit my hands.
There was one in particular that felt right for the tool size and type of
work I would be doing so decided to use it as a guide.
I chose cherry for the handles because I like the way it
turns on the lathe and the nice rich reddish color it develops over time. I started by cutting 7 blanks about 4” long
and just over 1” square. Using my center
finder I marked the centers of the blanks.
Below are top and bottom photos of it.
In use the 90-degree corner on the bottom goes against the corner of the
piece and the straight side of the opening lines up with the corner providing a
45-degree line as a diagonal. If you
mark all four corners and the piece is exactly square you get two lines with
the center where they cross. If it is
out of square then there will be multiple lines like the right image below.
Once I have my guide lines I use an awl to make a dimple
at the center. In order to get as close
as I could I used a set of magnifying glasses.
Maybe a bit of overkill but the final size of the handles are going to
be pretty close to the size of the blanks and I wanted to get the center point
as close as reasonably possible.
Below on the left are four of the blanks with punched
centers. With the centers marked I could
use a mallet to set the drive and was ready to start turning. The drive I used and what the blank end looks
like is on the right.
With the blank mounted in the lathe and using a roughing
gouge I turned each blank round. Here is
the typical progression through to a cylinder.
When done I had 6 nice round cylinders all the same diameter and length.
To prevent splitting the handle in use I will add a
copper ferrule at the narrow end where the riffler goes in the handle. The ferrule is made from a 3/8” hard copper
tube union cut in half. The inside of
the fitting is ½”. This begs the
question, if the fitting is for a 3/8” tube how can the inside diameter of the
coupling be ½”. Short answer is the 3/8”
refers to the inside diameter of the pipe having an outside diameter of ½”
which the coupling has to fit over.
Anyway, my first attempt to cut the fitting was to put it on a ½”
diameter dowel rod then used a tube cutter make the cut. Unfortunately, the fitting just spun on the
dowel rod as there was not enough friction between it and the fitting to hold
it.
The second attempt worked a lot better. I cut a lengthwise slot in the dowel slid the
fitting on as before and jammed a small screwdriver in the slot to act as a
wedge. This worked just fine. The left image below shows the setup and the
right one is a close up of the coupling.
The tube cutter is not a saw, does not remove material and does not
leave a kerf. As the cutter is spun around
the fitting its handle is tightened a fraction of a turn forcing the sharp
wheel into the fitting. The right image
shows the cutter wheel about half way through the fitting.
Once cut I had two pieces I could use for the
ferrules. If you look close at the left
piece you can see the sharp burr that rolls inside the piece left by the
cutter. The bigger problem is the
manufactures name “NIBCO” stamped into it.
I really do not want that to show when I am done.
The burr is easily removed using a small round file and
some emery cloth. The “NIBCO” stamp
requires a little more work. I started
by turning a slightly tapered mandrel then jammed the fitting on. The top photo has the fitting on the mandrel
mounted in the scroll chuck. The bottom
is just a closer look showing the “NIBCO” stamp I want to get rid of.
Since the stamp is only a about a hundredth of an inch
deep and the fitting walls are about 6.5 hundredths thick I felt like it was OK
to just file it down. Running the lathe
at a low speed I gently filed away the “NIBCO” stamp. Really the most time-consuming part was
cleaning the teeth in the file as they kept getting clogged up with the
copper. The top photo shows the stamp
gone except for just a little bit of the “O”.
Since I wanted a more finished surface I worked it down with abrasives
ending up wet sanding with 1,500 grit silicon carbide paper. Last touch is to burnish using 0000 steel
wool giving me the finish shown on the bottom photo. I could have gone farther using polishing
wheels and Tripoli then rouge to get a mirror surface but this is going to be a
working tool not a decorative item.
The last bit of work on the ferrules is to flatten the
edge that will butt up against the wood.
Here you can see the rough spots and burrs on the edge of the ferrule.
That gets fixed by making a few passes on a flat file
clamped to the workbench checking after each couple of passed to make sure the
edge is square to the sides. Here is
what the finished edge looks like setting on the file I used.
Next Up – Finishing the Handles
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