page10
page 46
Bamboo Journal
Italian Bamboo Rodmakers Association
Second, use a strip of tube, 50 mm diameter,
with emery paper pasted inside, to grind away
the few tenths of mm. to obtain a cylindrical
surface. Finish with ine emery paper.
It is important to note that by working by hand,
the sole will not be exactly cylindrical, but will
be very, very slightly cupped. I discovered that
this can be used to a great advantage, as discus-
sed later.
Renormalizing the curve blade bevel. The
surface of the bevel belongs to a cylindrical
surface. It is not possible to explain why here,
but the radius of the tube you will use to shape
the bevel is bigger than the radius of the base. It
depends on the bedding angle, the bevel angle,
as well as on radius of the shoe. For the Herdim
plane, the radius of the tube to use has a diame-
ter of 65 mm. The bedding angle of 35 degrees
must be kept steady by mounting the blade on a
guide and using templates to ensure that the
angle between the blade and the tube is correct.
I use a very simple and accurate guide built by
Richard Kell, which appears in the photo where
I also show a sharpened blade.
Please note that the use of a template to set the
grinding angle is essential, as the grinding
surface is below the plane where the guide rolls
(do not use the table of blade protrusions you
receive with the guide). Small adjustments
around 35 degrees may be necessary, as the
inal result you want to achieve is that the blade
edge protrudes uniformly from the shoe.
Beware that this is not the usual recommenda-
tion given in woodworking books, which recco-
mend that the blade protrudes more on the
center of the sole. This is perhaps one the most
delicate tunings you have to go through.
An alternative method to work the bevel (it is
the one I use, but it is a bit more expensive and
laborious) is to use the tube with emery paper
pasted on the outside of tube to form grooves
on Japanese stones of 250, 1200,5000 and 8000.
I work by hand for the roughing on the 250,
frequently redressing the groove, and then pass
to the iner stones using the Kell guide. You
decide! Obviously, the small plane cannot be
used free hand, as you would have no control.
You must use a guide that runs astride the beam
edges and keeps the plane well centered. This
will be discussed in the next chapter.
3. The plane-bearing guide.
The luthier plane is placed in a guide that runs
without play along the edges of the square
former beam. The guide is essentially a rectan-
gular box, without the lid and (almost) without
the bottom. It is made of mahogany, with inserts
made with ine birch plywood (the AVIO type
one used for for lying models, with very ine
layers). All the parts are made and squared, or
planed at 45 degrees accurately using the
shooting board method (see below), so that all
the joints are seamless. Small diameter bamboo
nails are used to add strength to glued joints
between the sides and the front and back.
The luthier plane has lat and parallel sides and
sits with a tight it inside the guide box. It can be
pushed down in the box sliding along the sides.
The front and back and the back of the box
allow a substantial play so that the box can be
easily inserted with a rocking motion. To
prevent the plane to be pushed out of the box,
two stops made of birch ply are glued to the
mahogany sides at the bottom of the “box”. The
sides together with the fences are planed at 45
degree with the shooting board. A photo from
below shows these two composite surfaces.
They are the surfaces that will slide along the
former beam sides.