Italian Bamboo Rodmakers Association Year 3 Number 5 December ...

Page 6
Bamboo Journal
So what can be done
There are a few methods and in particular the ones
described in Jack Howell’s wonderful book. One of
these is to use a rubber rolling pin (which is excellent
to push the deformation along) and the other is to roll
the blank on an adequate flat surface. Both systems
need to deal with the fact that the blanks are bound
with cord and especially at the extremities there are
swellings caused by the knots on the binding cord.
This is particularly annoying with the tips at the thin
end where the knot can be double the size of the
blank. Ideally we should rotate the blank around its
central axis with a thousand magic fingers that keep
the blank in this perfectly aligned position and while
rotating these ideal fingers would have to compress
the blank towards its centre , so that the bends could
be pushed out from the blank. All this seems quite
difficult but it can be achieved at very little expense:
two quite thick plywood planks that are at least 15 mm
thick, 140 cm long and 20 cm wide (these dimensions
are not critical); two pieces of foam rubber like the
ones the campers use or 10mm thick neoprene to
cover the planks. Then some talcum powder like the
one that is used to keep rubber dinghies during the
off season – technically its magnesium silicate but any
talcum powder will do (Tim Anderson suggested that
even plain bread flower will do too) .
This is how it works: one plank is placed on a table
and is dusted liberally with powder, the glued and
wrapped blank is placed on the plank (covered with
foam or neoprene). The powder helps to absorb the
excess glue so that the surface of the foam doesn’t get
soiled with the excess glue. On top of this you place
the second plank covered with foam and dusted with
powder so that the blank can roll on the bottom plank.
Because they both have the same elasticity and they
and yielding in the same way, the symmetrical axis is
automatically maintained even in the places where the
bind cord knots are. Continue rolling maintaining
pressure re leasing gradually when you stop.
Check if the blank is straight by sighting it lengthways.
Wait until the glue has set sufficiently before picking it
up.
Italian Bamboo Rodmakers Association