page12
page 48
Bamboo Journal
Italian Bamboo Rodmakers Association
Once the luthier plane sole rests onto the
plywood stop, minute rocking motions can be
performed because of the slightly dished sole.
This small rocking of the plane is precious in the
lasts passes of the plane, when the shavings
become automatically extremely thin. I have
found that it is essential to allow the plane to
take the position that best allows it to remove
material. This will be discussed briely in the
next chapter. The rocking of the luthier plane is
obtained by alternatively pressing the plane in
the front and in the back. The plane will never
remove material unnecessarily because of the
rocking. On the contrary, working with blocked
planes, I noticed that occasionally the depth of
the groove was a mil or so higher than expected.
I have no explanation why this happens. The
rocking can be more easily done using the new
micro ledge and ball handles offered by
DICTUM. They transform the small planes from
“inger plane” to “palm plane” and they are
shown in some of the photos. The peculiarity of
the loating plane can be described by the term
“Rock and No Roll”. I thank the DICTUM techni-
cal staff for generous advice about reshaping
the brass body.
Finally, an important detail. Because the former
beam is squared with great precision (90
degrees to better than 0.1 degree) it is necessa-
ry that the sliding surfaces of the guide equally
accurate. This cannot be achieved during the the
assembly of the various parts. So once the guide
is completed, the sliding surfaces are tuned by
using a block plane. The tuning is done by
resting the sidewing of the block plane on one
of the surfaces and working the other, and then
doing the reverse. The operation is very similar
to the use of a shooting board, briely discussed
below.
There is no space to describe in detail how to
setup and use a shooting board, and you can
ind a lot of material on the web on the subject.
I will however add a photo showing a 45 degre-
es shooting board in use to generate the 45
degrees sliding surface on one of the
mahogany-birch plywood sides of the guide.
The shooting board technique excels in the
working of small pieces, included those so small
they hardly it in a vice. It guarantees squared or
splined surfaces at any angle with great preci-
sion. All the guides that appear in the photos
shown here were made using various shooting
boards. For correctness, I must say that in the
photo above I show a Jackplane and not a block
plane. The work can also be done with the block
plane, and in the instructions of the Veritas
block plane, it is described how it can be used in
connection with a shooting board.
In the same chapter there is the description of a
guide very similar to the one described above
and used to hold a dial indicator, the instrument
to read the depth of the tracks. The guide and
guide will need a zero calibration, as usual. To
this end, you could use a cylinder of about two
cm diameter onto which you will to put the
guide astride, and block the dial barrel so that
the reading is the correct one. For reasons of
space, I cannot elaborate this point any further
here.
I advise you against using the standard point the
dial comes with, the one with a small diameter
ball. It will indent slightly the ir groove, and
reading will shift in time by one or two mils.
I use a Mitutoyo roller point as it does not
indent the tracks due to the generous curved
radiuses at the point of contact. It rolls smo-
othly on the bottom of the cylindrical groove,
and it gives reliable readings.